Part II

 
CONTENT

[Federal Register: May 4, 2005 (Volume 70, Number 85)]

[Proposed Rules]

[Page 23305-23673]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr04my05-18]

[[Page 23305]]

Part II

Department of Health and Human Services

Centers for Medicare & Medicaid Services

42 CFR Parts 405, 412, et al.

Medicare Program; Proposed Changes to the Hospital Inpatient Prospective Payment Systems and Fiscal Year 2006 Rates; Proposed Rule

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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Centers for Medicare & Medicaid Services

42 CFR Parts 405, 412, 413, 415, 419, 422, and 485

[CMS-1500-P]

RIN 0938-AN57

Medicare Program; Proposed Changes to the Hospital Inpatient Prospective Payment Systems and Fiscal Year 2006 Rates

AGENCY: Centers for Medicare and Medicaid Services (CMS), HHS.

ACTION: Proposed rule.

SUMMARY: We are proposing to revise the Medicare hospital inpatient prospective payment systems (IPPS) for operating and capital-related costs to implement changes arising from our continuing experience with these systems. In addition, in the Addendum to this proposed rule, we describe the proposed changes to the amounts and factors used to determine the rates for Medicare hospital inpatient services for operating costs and capital-related costs. We also are setting forth proposed rate-of-increase limits as well as proposed policy changes for hospitals and hospital units excluded from the IPPS that are paid in full or in part on a reasonable cost basis subject to these limits. These proposed changes would be applicable to discharges occurring on or after October 1, 2005, with one exception: The proposed changes relating to submittal of hospital wage data by a campus or campuses of a multicampus hospital system (that is, the proposed changes to Sec. 412.230(d)(2) of the regulations) would be effective upon publication of the final rule.

Among the policy changes that we are proposing to make are changes relating to: the classification of cases to the diagnosis-related groups (DRGs); the long-term care (LTC)-DRGs and relative weights; the wage data, including the occupational mix data, used to compute the wage index; rebasing and revision of the hospital market basket; applications for new technologies and medical services add-on payments; policies governing postacute care transfers, payments to hospitals for the direct and indirect costs of graduate medical education, submission of hospital quality data, payment adjustment for low-volume hospitals, changes in the requirements for provider-based facilities; and changes in the requirements for critical access hospitals (CAHs).

DATES: Comments will be considered if received at the appropriate address, as provided in the ADDRESSES section, no later than 5 p.m. on June 24, 2005.

ADDRESSES: In commenting, please refer to file code CMS-1500-P. Because of staff and resource limitations, we cannot accept comments by facsimile (FAX) transmission.

You may submit comments in one of three ways (no duplicates, please):

1. Electronically

You may submit electronic comments to http://www.cms.hhs.gov/regulations/ecomments (attachments should be in Microsoft Word,

WordPerfect, or Excel; however, we prefer Microsoft Word).

2. By Mail

You may mail written comments (one original and two copies) to the following address only: Centers for Medicare & Medicaid Services, Department of Health and Human Services, Attention: CMS-1500-P, P.O. Box 8011, Baltimore, MD 21244-1850.

Please allow sufficient time for mailed comments to be received before the close of the comment period.

3. By Hand or Courier

If you prefer, you may deliver (by hand or courier) your written comments (one original and two copies) before the close of the comment period to one of the following addresses. If you intend to deliver your comments to the Baltimore address, please call telephone number (410) 786-7195 in advance to schedule your arrival with one of our staff members.

Room 445-G, Hubert H. Humphrey Building, 200 Independence Avenue, SW., Washington, DC 20201, or 7500 Security Boulevard, Baltimore, MD 21244-1850.

(Because access to the interior of the Hubert H. Humphrey Building is not readily available to persons without Federal Government identification, commenters are encouraged to leave their comments in the CMS drop slots located in the main lobby of the building. A stamp- in clock is available for persons wishing to retain proof of filing by stamping in and retaining an extra copy of the comments being filed.)

Comments mailed to the addresses indicated as appropriate for hand or courier delivery may be delayed and received after the comment period.

Inspection of Public Comments: All comments received before the close of the comment period are available for viewing by the public, including any personally identifiable or confidential business information that is included in a comment. After the close of the comment period, CMS posts all electronic comments received before the close of the comment period on its public Web site. Written comments received timely will be available for public inspection as they are received, generally beginning approximately 4 weeks after publication of a document, at the headquarters of the Centers for Medicare & Medicaid Services, 7500 Security Boulevard, Baltimore, MD 21244, Monday through Friday of each week from 8:30 a.m. to 4 p.m. To schedule an appointment to view public comments, phone 1-800-743-3951.

For comments that relate to information collection requirements, mail a copy of comments to the following addresses:

Centers for Medicare & Medicaid Services, Office of Strategic Operations and Regulatory Affairs, Security and Standards Group, Office of Regulations Development and Issuances, Room C4-24-02 7500 Security Boulevard, Baltimore, Maryland 21244-1850, Attn: James Wickliffe, CMS- 1500-P; and Office of Information and Regulatory Affairs, Office of Management and Budget, Room 3001, New Executive Office Building, Washington, DC 20503, Attn: Christopher Martin, CMS Desk Officer, CMS-1500-P, Christopher_Martin@omb.eop.gov. Fax (202) 395-6974.

FOR FURTHER INFORMATION CONTACT:

Marc Harstein, (410) 786-4539, Operating Prospective Payment, Diagnosis-Related Groups (DRGs), Wage Index, New Medical Services and Technology Add-On Payments, Hospital Geographic Reclassifications, Postacute Care Transfers, and Disproportionate Share Hospital Issues. Tzvi Hefter, (410) 786-4487, Capital Prospective Payment, Excluded Hospitals, Graduate Medical Education, Critical Access Hospitals, and Long-Term Care (LTC)-DRGs, and Provider-Based Facilities Issues. Steve Heffler, (410) 786-1211, Hospital Market Basket Revision and Rebasing. Siddhartha Mazumdar, (410) 786-6673, Rural Hospital Community Demonstration Project Issues. Mary Collins, (410) 786-3189, Critical Access Hospitals (CAHs) Issues. Dr. Mark Krushat, (410) 786-6809, Quality Data for Annual Payment Update Issues. Martha Kuespert, (410) 786-4605 Specialty Hospitals Definition Issues.

SUPPLEMENTARY INFORMATION:

Electronic Access

This Federal Register document is also available from the Federal Register

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online database through GPO Access, a service of the U.S. Government Printing Office. Free public access is available on a Wide Area Information Server (WAIS) through the Internet and via asynchronous dial-in. Internet users can access the database by using the World Wide Web; the Superintendent of Documents home page address is http://www.access. gpo.gov/nara--docs, by using local WAIS client software, or

by telnet to swais.access.gpo.gov, then login as guest (no password required). Dial-in users should use communications software and modem to call (202) 512-1661; type swais, then login as guest (no password required).

Acronyms

AAOS American Association of Orthopedic Surgeons ACGME Accreditation Council on Graduate Medical Education AHIMA American Health Information Management Association AHA American Hospital Association AICD Automatic cardioverter defibrillator AMI Acute myocardial infarction AOA American Osteopathic Association ASC Ambulatory Surgical Center ASP Average sales price AWP Average wholesale price BBA Balanced Budget Act of 1997, Pub. L. 105-33 BES Business Expenses Survey BIPA Medicare, Medicaid, and SCHIP [State Children's Health Insurance Program] Benefits Improvement and Protection Act of 2000, Pub. L. 106-554 BLS Bureau of Labor Statistics CAH Critical access hospital CBSAs Core-Based Statistical Areas CC Complication or comorbidity CIPI Capital Input Price Index CMS Centers for Medicare & Medicaid Services CMSA Consolidated Metropolitan Statistical Area COBRA Consolidated Omnibus Reconciliation Act of 1985, Pub. L. 99- 272 CoP Condition of Participation CPI Consumer Price Index CRNA Certified registered nurse anesthetist CRT Cardiac Resynchronization Therapy DRG Diagnosis-related group DSH Disproportionate share hospital ECI Employment Cost Index FDA Food and Drug Administration FIPS Federal Information Processing Standards FQHC Federally qualified health center FTE Full-time equivalent FY Federal fiscal year GAAP Generally accepted accounting principles GAF Geographic adjustment factor HIC Health Insurance Card HIS Health Information System GME Graduate medical education HCRIS Hospital Cost Report Information System HIPC Health Information Policy Council HIPAA Health Insurance Portability and Accountability Act of 1996, Pub. L. 104-191 HHA Home health agency HHS Department of Health and Human Services HPSA Health Professions Shortage Area HQA Hospital Quality Alliance ICD-9-CM International Classification of Diseases, Ninth Revision, Clinical Modification ICD-10-PCS International Classification of Diseases, Tenth Edition, Procedure Coding System ICF/MRs Intermediate care facilities for the mentally retarded ICU Intensive Care Unit IHS Indian Health Service IME Indirect medical education IPPS Acute care hospital inpatient prospective payment system IPF Inpatient psychiatric facility IRF Inpatient rehabilitation facility IRP Initial residency period JCAHO Joint Commission on Accreditation of Healthcare Organizations LAMCs Large area metropolitan counties LTC-DRG Long-term care diagnosis-related group LTCH Long-term care hospital MCE Medicare Code Editor MCO Managed care organization MDC Major diagnostic category MDH Medicare-dependent small rural hospital MedPAC Medicare Payment Advisory Commission MedPAR Medicare Provider Analysis and Review File MEI Medicare Economic Index MGCRB Medicare Geographic Classification Review Board MMA Medicare Prescription Drug, Improvement, and Modernization Act of 2003, Pub. L. 108-173 MRHFP Medicare Rural Hospital Flexibility Program MSA Metropolitan Statistical Area NAICS North American Industrial Classification System NCD National coverage determination NCHS National Center for Health Statistics NCVHS National Committee on Vital and Health Statistics NECMA New England County Metropolitan Areas NICU Neonatal intensive care unit NQF National Quality Forum NTIS National Technical Information Service NVHRI National Voluntary Hospital Reporting Initiative OES Occupational Employment Statistics OIG Office of the Inspector General OMB Executive Office of Management and Budget O.R. Operating room OSCAR Online Survey Certification and Reporting (System) OSHA Occupational Safety and Health Act PRM Provider Reimbursement Manual PPI Producer Price Index PMS Performance Measurement System PMSAs Primary Metropolitan Statistical Areas PPS Prospective payment system PRA Per resident amount ProPAC Prospective Payment Assessment Commission PRRB Provider Reimbursement Review Board PS&R Provider Statistical and Reimbursement System QIA Quality Improvement Organizations RHC Rural health clinic RHQDAPU Reporting Hospital Quality Data for Annual Payment Update RNHCI Religious nonmedical health care institution RRC Rural referral center RUCAs Rural-Urban Commuting Area Codes SCH Sole community hospital SDP Single Drug Pricer SIC Standard Industrial Codes SNF Skilled nursing facility SOCs Standard occupational classifications SOM State Operations Manual SSA Social Security Administration SSI Supplemental Security Income TEFRA Tax Equity and Fiscal Responsibility Act of 1982, Pub. L. 97- 248 UHDDS Uniform Hospital Discharge Data Set

Table of Contents

I. Background

A. Summary

1. Acute Care Hospital Inpatient Prospective Payment System (IPPS)

2. Hospitals and Hospital Units Excluded from the IPPS

a. IRFs

b. LTCH

c. IPFs

3. Critical Access Hospitals (CAHs)

4. Payments for Graduate Medical Education (GME)

B. Major Contents of this Proposed Rule

1. Proposed Changes to the DRG Reclassifications and Recalibrations of Relative Weights

2. Proposed Changes to the Hospital Wage Index

3. Proposed Revision and Rebasing of the Hospital Market Basket

4. Other Decisions and Proposed Changes to the PPS for Inpatient Operating and GME Costs

5. PPS for Capital-Related Costs

6. Proposed Changes for Hospitals and Hospital Units Excluded from the IPPS

7. Proposed Payment for Blood Clotting Factors for Inpatients with Hemophilia

8. Determining Proposed Prospective Payment Operating and Capital Rates and Rate-of-Increase Limits

9. Impact Analysis

10. Recommendation of Update Factor for Hospital Inpatient Operating Costs

11. Discussion of Medicare Payment Advisory Commission Recommendations II. Proposed Changes to DRG Classifications and Relative Weights

A. Background

B. DRG Reclassifications

1. General

2. Pre-MDC: Intestinal Transplantation

3. MDC 1 (Diseases and Disorders of the Nervous System)

a. Strokes

b. Unruptured Cerebral Aneurysms

4. MDC 5 (Diseases and Disorders of the Circulatory System)

a. Automatic Implantable Cardioverter/Defibrillator

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b. Coronary Artery Stents

c. Insertion of Left Atrial Appendage Device

d. External Heart Assist System Implant

e. Carotid Artery Stent

f. Extracorporeal Membrane Oxygenation (ECMO)

5. MDC 6 (Diseases and Disorders of the Digestive System): Artificial Anal Sphincter

6. MDC 8 (Diseases and Disorders of the Musculoskeletal System and Connective Tissue)

a. Hip and Knee Replacements

b. Kyphoplasty

c. Multiple Level Spinal Fusion

7. MDC 18 (Infectious and Parasitic Diseases (Systemic or Unspecified Sites)): Severe Sepsis

8. MDC 20 (Alcohol/Drug Use and Alcohol/Drug Induced Organic Mental Disorders): Drug-Induced Dementia

9. Medicare Code Editor (MCE) Changes

a. Newborn Age Edit

b. Newborn Diagnoses Edit

c. Diagnoses Allowed for ``Males Only'' Edit

d. Tobacco Use Disorder Edit

e. Noncovered Procedure Edit

10. Surgical Hierarchies

11. Refinement of Complications and Comorbidities (CC) List

a. Background

b. Comprehensive Review of the CC List

c. CC Exclusion List for FY 2006

12. Review of Procedure Codes in DRGs 468, 476, and 477

a. Moving Procedure Codes from DRG 468 or DRG 477 to MDCs

b. Reassignment of Procedures among DRGs 468, 476, and 477

c. Adding Diagnosis or Procedure Codes to MDCs

13. Changes to the ICD-9-CM Coding System

14. Other Issues: Acute Intermittent Porphyria

C. Proposed Recalibration of DRG Weights

D. Proposed LTC-DRG Reclassifications and Relative Weights for LTCHs for FY 2006

1. Background

2. Proposed Changes in the LTC-DRG Classifications

a. Background

b. Patient Classifications into DRGs

3. Development of the Proposed FY 2006 LTC-DRG Relative Weights

a. General Overview of Development of the LTC-DRG Relative Weights

b. Data

c. Hospital-Specific Relative Value Methodology

d. Proposed Low-Volume LTC-DRGs

4. Steps for Determining the Proposed FY 2006 LTC-DRG Relative Weights

E. Proposed Add-On Payments for New Services and Technologies

1. Background

2. FY 2006 Status of Technology Approved for FY 2005 Add-On Payments

3. Reevaluation of FY 2005 Applications That Were Not Approved

4. FY 2006 Applicants for New Technology Add-On Payments III. Proposed Changes to the Hospital Wage Index

A. Background

B. Core-Based Statistical Areas for the Proposed Hospital Wage Index

C. Proposed Occupational Mix Adjustment to FY 2006 Index

1. Development of Data for the Proposed Occupational Mix Adjustment

2. Calculation of the Proposed Occupational Mix Adjustment Factor and the Proposed Occupational Mix Adjusted Wage Index

D. Worksheet S-3 Wage Data for the Proposed FY 2006 Wage Index Update

E. Verification of Worksheet S-3 Wage Data

F. Computation of the Proposed FY 2006 Unadjusted Wage Index

G. Computation of the Proposed FY 2006 Blended Wage Index

H. Proposed Revisions to the Wage Index Based on Hospital Redesignation

1. General

2. Effects of Reclassification

3. Proposed Application of Hold Harmless Protection for Certain Urban Hospitals Redesignated as Rural

4. FY 2006 MGCRB Reclassifications

5. Proposed FY 2006 Redesignations under Section 1886(d)(8)(B) of the Act

6. Reclassifications under Section 508 of Pub. L. 108-173

I. Proposed FY 2006 Wage Index Adjustment Based on Commuting Patterns of Hospital Employees

J. Process for Requests for Wage Index Data Corrections IV. Proposed Rebasing and Revision of the Hospital Market Baskets

A. Background

B. Rebasing and Revising the Hospital Market Basket

1. Development of Cost Categories and Weights

2. PPS--Selection of Price Proxies

3. Labor-Related Share

C. Separate Market Basket for Hospitals and Hospital Units Excluded from the IPPS

1. Hospitals Paid Based on Their Reasonable Costs

2. Excluded Hospitals Paid Under Blend Methodology

3. Development of Cost Categories and Weights for the Proposed 2002-Based Excluded Hospital Market Basket

D. Frequency of Updates of Weights in IPPS Hospital Market Basket

E. Capital Input Price Index Section V. Other Decisions and Proposed Changes to the IPPS for Operating Costs and GME Costs

A. Postacute Care Transfer Payment Policy

1. Background

2. Changes to DRGs Subject to the Postacute Care Transfer Policy

B. Reporting of Hospital Quality Data for Annual Hospital Payment Update

1. Background

2. Requirements for Hospital Reporting of Quality Data

C. Sole Community Hospitals and Medicare Dependent Hospitals

1. Background

2. Budget Neutrality Adjustment to Hospital Payments Based on Hospital-Specific Rate

3. Technical Change

D. Rural Referral Centers

1. Case-Mix Index

2. Discharges

3. Technical Change

E. Payment Adjustment for Low-Volume Hospitals

F. Indirect Medical Education (IME) Adjustment

1. Background

2. IME Adjustment for TEFRA Hospitals Converting to IPPS Hospitals

3. Section 1886(d)(3)(E) Teaching Hospitals That Withdraw Rural Reclassification

G. Payment to Disproportionate Share Hospitals (DSHs)

1. Background

2. Implementation of Section 951 of Pub. L. 108-173

H. Geographic Reclassifications

1. Background

2. Multicampus Hospitals

3. Urban Group Hospital Reclassifications

4. Clarification of Goldsmith Modification Criterion for Urban Hospitals Seeking Reclassification as Rural

I. Payment for Direct Graduate Medical Education

1. Background

2. Direct GME Initial Residency Period

a. Background

b. Direct GME Initial Residency Period Limitation: Simultaneous Match

3. New Teaching Hospitals' Participation in Medicare GME Affiliated Groups

4. GME FTE Cap Adjustments for Rural Hospitals

5. Technical Changes: Cross-References

J. Provider-Based Status of Facilities under Medicare

1. Background

2. Limits on Scope of Provider-Based Regulations--Facilities for Which Provider-Based Determinations Will Not Be Made

3. Location Requirement for Off-Campus Facilities: Application to Certain Neonatal Intensive Care Units

4. Technical and Clarifying Changes

K. Rural Community Hospital Demonstration Program

L. Definition of a Hospital in Connection with Specialty Hospitals VI. PPS for Capital-Related Costs VII. Proposed Changes for Hospitals and Hospital Units Excluded from the IPPS

A. Payments to Excluded Hospitals and Hospital Units

1. Payments to Existing Excluded Hospitals and Hospital Units

2. Updated Caps for New Excluded Hospitals and Units

3. Implementation of a PPS for IRFs

4. Implementation of a PPS for LTCHs

5. Implementation of a PPS for IPFs

B. Critical Access Hospitals (CAHs)

1. Background

2. Proposed Policy Change Relating to Continued Participation by CAHs in Lugar Counties

3. Proposed Policy Change Relating to Designation of CAHs as Necessary Providers

a. Determination of the Relocation Status of a CAH

b. Relocation of a CAH Using a Waiver to Meet the CoP for Distance

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VIII. Payment for Blood Clotting Factor Administered to Hemophilia Inpatients IX. MedPAC Recommendations

A. Medicare Payment Policy

B. Physician-Owned Specialty Hospitals

C. Other MedPAC Recommendations X. Other Required Information

A. Requests for Data from the Public

B. Collection of Information Requirements

C. Public Comments

Regulation Text

Addendum--Proposed Schedule of Standardized Amounts Effective with Discharges Occurring On or After October 1, 2004 and Update Factors and Rate-of-Increase Percentages Effective With Cost Reporting Periods Beginning On or After October 1, 2004 I. Summary and Background II. Proposed Changes to Prospective Payment Rates for Hospital Inpatient Operating Costs for FY 2006

A. Calculation of the Adjusted Standardized Amount

1. Standardization of Base-Year Costs or Target Amounts

2. Computing the Average Standardized Amount

3. Updating the Average Standardized Amount

4. Other Adjustments to the Average Standardized Amount

a. Recalibration of DRG Weights and Updated Wage Index--Budget Neutrality Adjustment

b. Reclassified Hospitals--Budget Neutrality Adjustment

c. Outliers

d. Rural Community Hospital Demonstration Program Adjustment (Section 410A of Pub. L. 108-173)

5. Proposed FY 2006 Standardized Amount

B. Adjustments for Area Wage Levels and Cost-of-Living

1. Adjustment for Area Wage Levels

2. Adjustment for Cost-of-Living in Alaska and Hawaii

C. DRG Relative Weights

D. Calculation of Proposed Prospective Payment Rates for FY 2006

1. Federal Rate

2. Hospital-Specific Rate (Applicable Only to SCHs and MDHs)

a. Calculation of Hospital-Specific Rate

b. Updating the FY 1982, FY 1987, and FY 1996 Hospital-Specific Rates for FY 2006

3. General Formula for Calculation of Proposed Prospective Payment Rates for Hospitals Located in Puerto Rico Beginning On or After October 1, 2005 and Before October 1, 2006

a. Puerto Rico Rate

b. National Rate III. Proposed Changes to Payment Rates for Acute Care Hospital Inpatient Capital-Related Costs for FY 2006

A. Determination of Proposed Federal Hospital Inpatient Capital- Related Prospective Payment Rate Update

1. Proposed Capital Standard Federal Rate Update

a. Description of the Update Framework

b. Comparison of CMS and MedPAC Update Recommendation

2. Proposed Outlier Payment Adjustment Factor

3. Proposed Budget Neutrality Adjustment Factor for Changes in DRG Classifications and Weights and the Geographic Adjustment Factor

4. Proposed Exceptions Payment Adjustment Factor

5. Proposed Capital Standard Federal Rate for FY 2006

6. Proposed Special Capital Rate for Puerto Rico Hospitals

B. Calculation of Proposed Inpatient Capital-Related Prospective Payments for FY 2006

C. Capital Input Price Index

1. Background

2. Forecast of the CIPI for FY 2006 IV. Proposed Changes to Payment Rates for Excluded Hospitals and Hospital Units: Rate-of-Increase Percentages

A. Payments to Existing Excluded Hospitals and Units

B. Updated Caps for New Excluded Hospitals and Units V. Payment for Blood Clotting Factor Administered to Hemophilia Inpatients

Tables

Table 1A--National Adjusted Operating Standardized Amounts, Labor/ Nonlabor (69.7 Percent Labor Share/30.3 Percent Nonlabor Share If Wage Index Is Greater Than 1) Table 1B--National Adjusted Operating Standardized Amounts, Labor/ Nonlabor (62 Percent Labor Share/38 Percent Nonlabor Share If Wage Index Is Less Than or Equal to 1) Table 1C--Adjusted Operating Standardized Amounts for Puerto Rico, Labor/Nonlabor Table 1D--Capital Standard Federal Payment Rate Table 2--Hospital Case-Mix Indexes for Discharges Occurring in Federal Fiscal Year 2004; Hospital Average Hourly Wage for Federal Fiscal Years 2004 (2000 Wage Data), 2005 (2001 Wage Data), and 2006 (2002 Wage Data) Wage Indexes and 3-Year Average of Hospital Average Hourly Wages Table 3A--FY 2006 and 3-Year Average Hourly Wage for Urban Areas Table 3B--FY 2006 and 3-Year Average Hourly Wage for Rural Areas Table 4A--Wage Index and Capital Geographic Adjustment Factor (GAF) for Urban Areas Table 4B--Wage Index and Capital Geographic Adjustment Factor (GAF) for Rural Areas Table 4C--Wage Index and Capital Geographic Adjustment Factor (GAF) for Hospitals That Are Reclassified Table 4F--Puerto Rico Wage Index and Capital Geographic Adjustment Factor (GAF) Table 4J--Out-Migration Adjustment--FY 2006 Table 5--List of Diagnosis-Related Groups (DRGs), Relative Weighting Factors, and Geometric and Arithmetic Mean Length of Stay (LOS) Table 6A--New Diagnosis Codes Table 6B--New Procedure Codes Table 6C--Invalid Diagnosis Codes Table 6D--Invalid Procedure Codes Table 6E--Revised Diagnosis Code Titles Table 6F--Revised Procedure Code Titles Table 6G--Additions to the CC Exclusions List Table 6H--Deletions from the CC Exclusions List Table 7A--Medicare Prospective Payment System Selected Percentile Lengths of Stay: FY 2004 MedPAR Update December 2004 GROUPER V22.0 Table 7B--Medicare Prospective Payment System Selected Percentile Lengths of Stay: FY 2004 MedPAR Update December 2004 GROUPER V23.0 Table 8A--Statewide Average Operating Cost-to-Charge Ratios--March 2005 Table 8B--Statewide Average Capital Cost-to-Charge Ratios--March 2005 Table 9A--Hospital Reclassifications and Redesignations by Individual Hospital--FY 2006 Table 9B--Hospital Reclassifications and Redesignation by Individual Hospital Under Section 508 of Pub. L. 108-173--FY 2005 Table 9C--Hospitals Redesignated as Rural under Section 1886(d)(8)(E) of the Act--FY 2006 Table 10--Geometric Mean Plus the Lesser of .75 of the National Adjusted Operating Standardized Payment Amount (Increased to Reflect the Difference Between Costs and Charges) or .75 of One Standard Deviation of Mean Charges by Diagnosis-Related Groups (DRGs)--March 2005 Table 11--Proposed FY 2006 LTC-DRGs, Relative Weights, Geometric Average Length of Stay, and 5/6ths of the Geometric Average Length of Stay Appendix A--Regulatory Impact Analysis Appendix B--Recommendation of Update Factors for Operating Cost Rates of Payment for Inpatient Hospital Services

I. Background

A. Summary

1. Acute Care Hospital Inpatient Prospective Payment System (IPPS)

Section 1886(d) of the Social Security Act (the Act) sets forth a system of payment for the operating costs of acute care hospital inpatient stays under Medicare Part A (Hospital Insurance) based on prospectively set rates. Section 1886(g) of the Act requires the Secretary to pay for the capital-related costs of hospital inpatient stays under a prospective payment system (PPS). Under these PPSs, Medicare payment for hospital inpatient operating and capital-related costs is made at predetermined, specific rates for each hospital discharge. Discharges are classified according to a list of diagnosis- related groups (DRGs).

The base payment rate is comprised of a standardized amount that is divided into a labor-related share and a nonlabor-related share. The labor-related share is adjusted by the wage index applicable to the area where the

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hospital is located; and if the hospital is located in Alaska or Hawaii, the nonlabor-related share is adjusted by a cost-of-living adjustment factor. This base payment rate is multiplied by the DRG relative weight.

If the hospital treats a high percentage of low-income patients, it receives a percentage add-on payment applied to the DRG-adjusted base payment rate. This add-on payment, known as the disproportionate share hospital (DSH) adjustment, provides for a percentage increase in Medicare payments to hospitals that qualify under either of two statutory formulas designed to identify hospitals that serve a disproportionate share of low-income patients. For qualifying hospitals, the amount of this adjustment may vary based on the outcome of the statutory calculations.

If the hospital is an approved teaching hospital, it receives a percentage add-on payment for each case paid under the IPPS (known as the indirect medical education (IME) adjustment). This percentage varies, depending on the ratio of residents to beds.

Additional payments may be made for cases that involve new technologies or medical services that have been approved for special add-on payments. To qualify, a new technology or medical service must demonstrate that it is a substantial clinical improvement over technologies or services otherwise available, and that, absent an add- on payment, it would be inadequately paid under the regular DRG payment.

The costs incurred by the hospital for a case are evaluated to determine whether the hospital is eligible for an additional payment as an outlier case. This additional payment is designed to protect the hospital from large financial losses due to unusually expensive cases. Any outlier payment due is added to the DRG-adjusted base payment rate, plus any DSH, IME, and new technology or medical service add-on adjustments.

Although payments to most hospitals under the IPPS are made on the basis of the standardized amounts, some categories of hospitals are paid the higher of a hospital-specific rate based on their costs in a base year (the higher of FY 1982, FY 1987, or FY 1996) or the IPPS rate based on the standardized amount. For example, sole community hospitals (SCHs) are the sole source of care in their areas, and Medicare- dependent, small rural hospitals (MDHs) are a major source of care for Medicare beneficiaries in their areas. Both of these categories of hospitals are afforded this special payment protection in order to maintain access to services for beneficiaries. (An MDH receives only 50 percent of the difference between the IPPS rate and its hospital- specific rates if the hospital-specific rate is higher than the IPPS rate. In addition, an MDH does not have the option of using FY 1996 as the base year for its hospital-specific rate.)

Section 1886(g) of the Act requires the Secretary to pay for the capital-related costs of inpatient hospital services ``in accordance with a prospective payment system established by the Secretary.'' The basic methodology for determining capital prospective payments is set forth in our regulations at 42 CFR 412.308 and 412.312. Under the capital PPS, payments are adjusted by the same DRG for the case as they are under the operating IPPS. Similar adjustments are also made for IME and DSH as under the operating IPPS. In addition, hospitals may receive an outlier payment for those cases that have unusually high costs.

The existing regulations governing payments to hospitals under the IPPS are located in 42 CFR part 412, Subparts A through M. 2. Hospitals and Hospital Units Excluded From the IPPS

Under section 1886(d)(1)(B) of the Act, as amended, certain specialty hospitals and hospital units are excluded from the IPPS. These hospitals and units are: Psychiatric hospitals and units; rehabilitation hospitals and units; long-term care hospitals (LTCHs); children's hospitals; and cancer hospitals. Various sections of the Balanced Budget Act of 1997 (Pub. L. 105-33), the Medicare, Medicaid and SCHIP [State Children's Health Insurance Program] Balanced Budget Refinement Act of 1999 (Pub. L. 106-113), and the Medicare, Medicaid, and SCHIP Benefits Improvement and Protection Act of 2000 (Pub. L. 106- 554) provide for the implementation of PPSs for rehabilitation hospitals and units (referred to as inpatient rehabilitation facilities (IRFs)), psychiatric hospitals and units (referred to as inpatient psychiatric facilities (IPFs)), and LTCHs, as discussed below. Children's hospitals and cancer hospitals continue to be paid under reasonable cost-based reimbursement.

The existing regulations governing payments to excluded hospitals and hospital units are located in 42 CFR Parts 412 and 413. a. IRFs

Under section 1886(j) of the Act, as amended, rehabilitation hospitals and units (IRFs) have been transitioned from payment based on a blend of reasonable cost reimbursement subject to a hospital-specific annual limit under section 1886(b) of the Act and the adjusted facility Federal prospective payment rate for cost reporting periods beginning January 1, 2002 through September 30, 2002, to payment at 100 percent of the Federal rate effective for cost reporting periods beginning on or after October 1, 2002 (66 FR 41316, August 7, 2001; 67 FR 49982, August 1, 2002; and 68 FR 45674, August 1, 2003). The existing regulations governing payments under the IRF PPS are located in 42 CFR Part 412, Subpart P. b. LTCHs

Under the authority of sections 123(a) and (c) of Pub. L. 106-113 and section 307(b)(1) of Pub. L. 106-554, LTCHs are being transitioned from being paid for inpatient hospital services based on a blend of reasonable cost-based reimbursement under section 1886(b) of the Act to 100 percent of the Federal rate during a 5-year period, beginning with cost reporting periods that start on or after October 1, 2002. For cost reporting periods beginning on or after October 1, 2006, LTCHs will be paid 100 percent of the Federal rate (May 7, 2004 LTCH PPS final rule (69 FR 25674)). LTCHs may elect to be paid based on 100 percent of the Federal rate instead of a blended payment in any year during the 5-year transition period. The existing regulations governing payment under the LTCH PPS are located in 42 CFR Part 412, Subpart O. c. IPFs

Under the authority of sections 124(a) and (c) of Pub. L. 106-113, inpatient psychiatric facilities (IPFs) (formerly psychiatric hospitals and psychiatric units of acute care hospitals) are paid under the new IPF PPS. Under the IPF PPS, some IPFs are transitioning from being paid for inpatient hospital services based on a blend of reasonable cost- based payment and a Federal per diem payment rate, effective for cost reporting periods beginning on or after January 1, 2005 (November 15, 2004 IPF PPS final rule (69 FR 66921)). For cost reporting periods beginning on or after July 1, 2008, IPFs will be paid 100 percent of the Federal per diem payment amount. The existing regulations governing payment under the IPF PPS are located in 42 CFR part 412, subpart N. 3. Critical Access Hospitals (CAHs)

Under sections 1814, 1820, and 1834(g) of the Act, payments are made to critical access hospitals (CAHs) (that is, rural hospitals or facilities that meet certain statutory requirements) for inpatient and outpatient services based

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on 101 percent of reasonable cost. Reasonable cost is determined under the provisions of section 1861(v)(1)(A) of the Act and existing regulations under 42 CFR Parts 413 and 415. 4. Payments for Graduate Medical Education (GME)

Under section 1886(a)(4) of the Act, costs of approved educational activities are excluded from the operating costs of inpatient hospital services. Hospitals with approved graduate medical education (GME) programs are paid for the direct costs of GME in accordance with section 1886(h) of the Act; the amount of payment for direct GME costs for a cost reporting period is based on the hospital's number of residents in that period and the hospital's costs per resident in a base year. The existing regulations governing payments to the various types of hospitals are located in 42 CFR Part 413.

On August 11, 2004, we published a final rule in the Federal Register (69 FR 48916) that implemented changes to the Medicare hospital inpatient prospective payment systems for both operating cost and capital-related costs, as well as changes addressing payments for excluded hospitals and payments for GME costs. Generally these changes were effective for discharges occurring on or after October 1, 2004. On October 7, 2004, we published a document in the Federal Register (69 FR 60242) that corrected technical errors made in the August 11, 2004 final rule. On December 30, 2004, we published another document in the Federal Register (69 FR 78525) that further corrected the August 11, 2004 final rule and the October 7, 2004 correction to that rule, effective January 1, 2005.

B. Major Contents of This Proposed Rule

In this proposed rule, we are setting forth proposed changes to the Medicare IPPS for operating costs and for capital-related costs in FY 2006. We also are setting forth proposed changes relating to payments for GME costs, payments to certain hospitals and units that continue to be excluded from the IPPS and paid on a reasonable cost basis, payments for DSHs, and requirements and payments for CAHs. The changes being proposed would be effective for discharges occurring on or after October 1, 2005, unless otherwise noted.

The following is a summary of the major changes that we are proposing to make: 1. Proposed Changes to the DRG Reclassifications and Recalibrations of Relative Weights

As required by section 1886(d)(4)(C) of the Act, in section II. of this proposed rule, we are proposing annual adjustments to the DRG classifications and relative weights. Based on analyses of Medicare claims data, we are proposing to establish a number of new DRGs and make changes to the designation of diagnosis and procedure codes under other existing DRGs.

The major DRG classification changes we are proposing include:

Reassigning procedure code 35.52 (Repair of atrial septal defect with prosthesis, closed technique) from DRG 108 to DRG 518 (Percutaneous Cardiovascular Procedure Without Coronary Artery Stent or AMI);

Reassigning procedure code 37.26 (Cardiac electrophysiologic stimulation and recording studies) from DRGs 535 and 536 to DRGs 515 (Cardiac Defibrillator Implant Without Cardiac Catheterization);

Splitting DRG 209 into two new DRGs based on the presence or absence of the procedure codes for major joint replacement or reattachment of lower extremity and revision of hip or knee replacement, DRG 545 (Revision of Hip or Knee Replacement) and DRG 544 (Major Joint Replacement or Reattachment of Lower Extremity);

Reassigning procedure code 26.12 (Open biopsy of salivary gland or duct) from DRG 468 to DRG 477 (Nonextensive O.R. Procedure Unrelated To Principal Diagnosis);

Reassigning the principal diagnosis codes for curvature of the spine or malignancy from DRGs 497 and 498 to proposed new DRG 546 (Spinal Fusion Except Cervical with PDX of Curvature of the Spine or Malignancy);

Splitting DRGs 516 and 526 into four new DRGs based on the presence or absence of a CC;

Reassigning procedure code 39.65 (Extracorporeal membrane oxygenation [ECMO]) from DRGs 104 and 105 to DRG 541 (ECMO or Tracheostomy with Mechanical Ventilation 96+ Hours or Principal Diagnosis Except Face, Mouth and Neck Diagnoses With Major Operating Room Procedure).

We also are presenting our reevaluation of certain FY 2005 applicants for add-on payments for high-cost new medical services and technologies, and our analysis of FY 2006 applicants (including public input, as directed by Pub. L. 108-173, obtained in a town hall meeting).

We are proposing the annual update of the long-term care diagnosis- related group (LTC-DRG) classifications and relative weights for use under the LTCH PPS for FY 2006. 2. Proposed Changes to the Hospital Wage Index

In section III. of this preamble, we are proposing revisions to the wage index and the annual update of the wage data. Specific issues addressed include the following:

The FY 2006 wage index update, using wage data from cost reporting periods that began during FY 2002.

The proposed occupational mix adjustment to the wage index that we began to apply effective October 1, 2004.

The proposed revisions to the wage index based on hospital redesignations and reclassifications.

The proposed adjustment to the wage index for FY 2006 based on commuting patterns of hospital employees who reside in a county and work in a different area with a higher wage index.

The timetable for reviewing and verifying the wage data that will be in effect for the proposed FY 2006 wage index. 3. Proposed Revision and Rebasing of the Hospital Market Baskets

In section IV. of this proposed rule, we are proposing rebasing and revising the hospital operating and capital market baskets to be used in developing the FY 2006 update factor for the operating prospective payment rates and the excluded hospital market basket to be used in developing the FY 2006 update factor for the excluded hospital rate-of- increase limits. We are also setting forth the data sources used to determine the revised market basket relative weights and choice of price proxies. 4. Other Decisions and Proposed Changes to the PPS for Inpatient Operating and GME Costs

In section V. of this proposed rule, we discuss a number of provisions of the regulations in 42 CFR Parts 412 and 413 and set forth proposed changes concerning the following:

Solicitation of public comments on two options for possible expansion of the current postacute care transfer policy.

The reporting of hospital quality data as a condition for receiving the full annual payment update increase.

Proposed changes in the payment adjustment for low-volume hospitals.

Proposed IME adjustment for TEFRA hospitals that are converting to IPPS hospitals, and IME FTE resident caps for urban hospitals that are granted

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rural reclassification and then withdraw that rural classification.

Proposed changes to implement section 951 of Pub. L. 108- 173 relating to the provision of patient stay/SSI days data maintained by CMS to hospitals for the purpose of determining their DSH percentage.

Proposed changes relating to hospitals' geographic classifications, including multicampus hospitals and urban group hospital reclassifications.

Proposed changes and clarifications relating to GME, including GME initial residency period limitation, new teaching hospitals' participation in Medicare GME affiliated groups, and the GME FTE cap adjustment for rural hospitals;

Solicitation of public comments on possible changes in requirements for provider-based entities relating to entities the location requirements for certain neonatal intensive care units as off- campus facilities;

Discussion of the second year of implementation of the Rural Community Hospital Demonstration Program; and

Clarification of the definition of a hospital as it relates to ``specialty hospitals'' participating in the Medicare program. 5. PPS for Capital-Related Costs

In section VI. of this proposed rule, we are not proposing any policy changes to the capital-related prospective payment system. For the readers' benefit, we discuss the payment policy requirements for capital-related costs and capital payments to hospitals. 6. Proposed Changes for Hospitals and Hospital Units Excluded From the IPPS

In section VII. of this proposed rule, we discuss the proposed revisions and clarifications concerning excluded hospitals and hospital units, proposed policy changes relating to continued participation by CAHs located in counties redesignated under section 1886(d)(8)(B) of the Act (Lugar counties), and proposed policy changes relating to designation of CAHs as necessary providers. 7. Proposed Changes in Payment for Blood Clotting Factor

In section VIII of this proposed rule, we discuss the proposed change in payment for blood clotting factor administered to inpatients with hemophilia for FY 2006. 8. Determining Prospective Payment Operating and Capital Rates and Rate-of-Increase Limits

In the Addendum to this proposed rule, we set forth proposed changes to the amounts and factors for determining the FY 2006 prospective payment rates for operating costs and capital-related costs. We also establish the proposed threshold amounts for outlier cases. In addition, we address the proposed update factors for determining the rate-of-increase limits for cost reporting periods beginning in FY 2006 for hospitals and hospital units excluded from the PPS. 9. Impact Analysis

In Appendix A of this proposed rule, we set forth an analysis of the impact that the proposed changes would have on affected hospitals. 10. Recommendation of Update Factor for Hospital Inpatient Operating Costs

In Appendix B of this proposed rule, as required by sections 1886(e)(4) and (e)(5) of the Act, we provided our recommendations of the appropriate percentage changes for FY 2006 for the following:

A single average standardized amount for all areas for hospital inpatient services paid under the IPPS for operating costs (and hospital-specific rates applicable to SCHs and MDHs).

Target rate-of-increase limits to the allowable operating costs of hospital inpatient services furnished by hospitals and hospital units excluded from the IPPS. 11. Discussion of Medicare Payment Advisory Commission Recommendations

Under section 1805(b) of the Act, the Medicare Payment Advisory Commission (MedPAC) is required to submit a report to Congress, no later than March 1 of each year, in which MedPAC reviews and makes recommendations on Medicare payment policies. MedPAC's March 2005 recommendation concerning hospital inpatient payment policies addressed only the update factor for inpatient hospital operating costs and capital-related costs under the IPPS and for hospitals and distinct part hospital units excluded from the IPPS. This recommendation is addressed in Appendix B of this proposed rule. MedPAC issued a second Report to Congress: Physician-Owned Specialty Hospitals, March 2005, which addressed other issues relating to Medicare payments to hospitals for inpatient services. The recommendations on these issues from this second report are addressed in section IX. of this preamble. For further information relating specifically to the MedPAC March 2005 reports or to obtain a copy of the reports, contact MedPAC at (202) 220-3700 or visit MedPAC's Web site at: http://www.medpac.gov.

II. Proposed Changes to DRG Classifications and Relative Weights

A. Background

Section 1886(d) of the Act specifies that the Secretary shall establish a classification system (referred to as DRGs) for inpatient discharges and adjust payments under the IPPS based on appropriate weighting factors assigned to each DRG. Therefore, under the IPPS, we pay for inpatient hospital services on a rate per discharge basis that varies according to the DRG to which a beneficiary's stay is assigned. The formula used to calculate payment for a specific case multiplies an individual hospital's payment rate per case by the weight of the DRG to which the case is assigned. Each DRG weight represents the average resources required to care for cases in that particular DRG, relative to the average resources used to treat cases in all DRGs.

Congress recognized that it would be necessary to recalculate the DRG relative weights periodically to account for changes in resource consumption. Accordingly, section 1886(d)(4)(C) of the Act requires that the Secretary adjust the DRG classifications and relative weights at least annually. These adjustments are made to reflect changes in treatment patterns, technology, and any other factors that may change the relative use of hospital resources. The proposed changes to the DRG classification system and the recalibration of the DRG weights for discharges occurring on or after October 1, 2005, are discussed below.

B. DRG Reclassifications

(If you choose to comment on issues in this section, please include the caption ``DRG Reclassifications'' at the beginning of your comment.) 1. General

Cases are classified into DRGs for payment under the IPPS based on the principal diagnosis, up to eight additional diagnoses, and up to six procedures performed during the stay. In a small number of DRGs, classification is also based on the age, sex, and discharge status of the patient. The diagnosis and procedure information is reported by the hospital using codes from the International

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Classification of Diseases, Ninth Revision, Clinical Modification (ICD- 9-CM).

The process of forming the DRGs was begun by dividing all possible principal diagnoses into mutually exclusive principal diagnosis areas referred to as Major Diagnostic Categories (MDCs). The MDCs were formed by physician panels as the first step toward ensuring that the DRGs would be clinically coherent. The diagnoses in each MDC correspond to a single organ system or etiology and, in general, are associated with a particular medical specialty. Thus, in order to maintain the requirement of clinical coherence, no final DRG could contain patients in different MDCs. Most MDCs are based on a particular organ system of the body. For example, MDC 6 is Diseases and Disorders of the Digestive System. This approach is used because clinical care is generally organized in accordance with the organ system affected. However, some MDCs are not constructed on this basis because they involve multiple organ systems (for example, MDC 22 (Burns)). For FY 2005, cases are assigned to one of 519 DRGs in 25 MDCs. The table below lists the 25 MDCs.

[GRAPHIC] [TIFF OMITTED] TP04MY05.000

In general, cases are assigned to an MDC based on the patient's principal diagnosis before assignment to a DRG. However, for FY 2005, there are nine DRGs to which cases are directly assigned on the basis of ICD-9-CM procedure codes. These DRGs are for heart transplant or implant of heart assist systems, liver and/or intestinal transplants, bone marrow, lung, simultaneous pancreas/kidney, and pancreas transplants and for tracheostomies. Cases are assigned to these DRGs before they are classified to an MDC. The table below lists the current nine pre-MDCs.

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[GRAPHIC] [TIFF OMITTED] TP04MY05.001

Once the MDCs were defined, each MDC was evaluated to identify those additional patient characteristics that would have a consistent effect on the consumption of hospital resources. Since the presence of a surgical procedure that required the use of the operating room would have a significant effect on the type of hospital resources used by a patient, most MDCs were initially divided into surgical DRGs and medical DRGs. Surgical DRGs are based on a hierarchy that orders operating room (O.R.) procedures or groups of O.R. procedures by resource intensity. Medical DRGs generally are differentiated on the basis of diagnosis and age (less than or greater than 17 years of age). Some surgical and medical DRGs are further differentiated based on the presence or absence of a complication or a comorbidity (CC).

Generally, nonsurgical procedures and minor surgical procedures that are not usually performed in an operating room are not treated as O.R. procedures. However, there are a few non-O.R. procedures that do affect DRG assignment for certain principal diagnoses, for example, extracorporeal shock wave lithotripsy for patients with a principal diagnosis of urinary stones.

Once the medical and surgical classes for an MDC were formed, each class of patients was evaluated to determine if complications, comorbidities, or the patient's age would consistently affect the consumption of hospital resources. Physician panels classified each diagnosis code based on whether the diagnosis, when present as a secondary condition, would be considered a substantial complication or comorbidity.

A substantial complication or comorbidity was defined as a condition, which because of its presence with a specific principal diagnosis, would cause an increase in the length of stay by at least one day in at least 75 percent of the patients. Each medical and surgical class within an MDC was tested to determine if the presence of any substantial comorbidities or complications would consistently affect the consumption of hospital resources.

The actual process of forming the DRGs was, and continues to be, highly iterative, involving a combination of statistical results from test data combined with clinical judgment. In deciding whether to create a separate DRG, we consider whether the resource consumption and clinical characteristics of the patients with a given set of conditions are significantly different than the remaining patients in the DRG. We evaluate patient care costs using average charges and length of stay as proxies for costs and rely on the judgment of our medical officers to decide whether patients are distinct or clinically similar to other patients in the DRG. In evaluating resource costs, we consider both the absolute and percentage differences in average charges between the cases we are selecting for review and the remainder of cases in the DRG. We also consider variation in charges within these groups; that is, whether observed average differences are consistent across patients or attributable to cases that are extreme in terms of charges or length of stay, or both. Further, we also consider the number of patients who will have a given set of characteristics and generally prefer not to create a new DRG unless it will include a substantial number of cases. As we explain in more detail in section IX. of this preamble, MedPAC has made a number of recommendations regarding the DRG system. As part of our review and analysis of MedPAC's recommendations, we will consider whether to establish guidelines for making DRG reclassification decisions.

A patient's diagnosis, procedure, discharge status, and demographic information is fed into the Medicare claims processing systems and subjected to a series of automated screens called the Medicare Code Editor (MCE). The MCE screens are designed to identify cases that require further review before classification into a DRG.

After patient information is screened through the MCE and any further development of the claim is conducted, the cases are classified into the appropriate DRG by the Medicare GROUPER software program. The GROUPER program was developed as a means of classifying each case into a DRG on the basis of the diagnosis and procedure codes and, for a limited number of DRGs, demographic information (that is, sex, age, and discharge status).

After cases are screened through the MCE and assigned to a DRG by the GROUPER, the PRICER software calculates a base DRG payment. The PRICER calculates the payments for each case covered by the IPPS based on the DRG relative weight and additional factors associated with each hospital, such as IME and DSH adjustments. These additional factors increase the payment amount to hospitals above the base DRG payment.

The records for all Medicare hospital inpatient discharges are maintained in the Medicare Provider Analysis and

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Review (MedPAR) file. The data in this file are used to evaluate possible DRG classification changes and to recalibrate the DRG weights. However, in the July 30, 1999 IPPS final rule (64 FR 41500), we discussed a process for considering non-MedPAR data in the recalibration process. In order for us to consider using particular non-MedPAR data, we must have sufficient time to evaluate and test the data. The time necessary to do so depends upon the nature and quality of the non-MedPAR data submitted. Generally, however, a significant sample of the non-MedPAR data should be submitted by mid-October for consideration in conjunction with the next year's proposed rule. This allows us time to test the data and make a preliminary assessment as to the feasibility of using the data. Subsequently, a complete database should be submitted by early December for consideration in conjunction with the next year's proposed rule.

Many of the changes to the DRG classifications are the result of specific issues brought to our attention by interested parties. We encourage individuals with concerns about DRG classifications to bring those concerns to our attention in a timely manner so they can be carefully considered for possible inclusion in the next proposed rule and if included, may be subjected to public review and comment. Therefore, similar to the timetable for interested parties to submit non-MedPAR data for consideration in the DRG recalibration process, concerns about DRG classification issues should be brought to our attention no later than early December in order to be considered and possibly included in the next annual proposed rule updating the IPPS.

The changes we are proposing to the DRG classification system for FY 2006 for the FY 2006 GROUPER, version 23.0 and to the methodology used to recalibrate the DRG weights are set forth below. Unless otherwise noted in this proposed rule, our DRG analysis is based on data from the December 2004 update of the FY 2004 MedPAR file, which contains hospital bills received through December 31, 2004 for discharges in FY 2004. 2. Pre-MDC: Intestinal Transplantation

In the FY 2005 IPPS final rule (69 FR 48976), we moved intestinal transplantation cases that were assigned to ICD-9-CM procedure code 46.97 (Transplant of intestine) out of DRG 148 (Major Small and Large Bowel Procedures with CC) and DRG 149 (Major Small and Large Bowel Procedures Without CC) and into DRG 480 (Liver Transplant). We also changed the title for DRG 480 to ``Liver Transplant and/or Intestinal Transplant.'' We moved these cases out of DRGs 148 and 149 because our analysis demonstrated that the average charges for intestinal transplants are significantly higher than the average charges for other cases in these DRGs. We stated at that time that we would continue to monitor these cases.

Based on our review of the FY 2004 MedPAR data, we found 959 cases assigned to DRG 480 with overall average charges of approximately $165,622. There were only three cases involving an intestinal transplant alone and one case in which both an intestinal transplant and a liver transplant were performed. The average charges for the intestinal transplant cases ($138,922) were comparable to the average charges for the liver transplant cases ($165,314), while the remaining combination of an intestinal transplant and a liver transplant case had much higher charges ($539,841), and would be paid as an outlier case. Therefore, we are not proposing any DRG modification for intestinal transplantation cases at this time.

We note that an institution that performs intestinal transplantation, in correspondence to us written following the publication of the FY 2005 IPPS final rule, agreed with our decision to move cases assigned to code 46.97 to DRG 480. 3. MDC 1 (Diseases and Disorders of the Nervous System) a. Strokes

In 1996, the Food and Drug Administration (FDA) approved the use of tissue plasminogen activator (tPA), one type of thrombolytic agent that dissolves blood clots. In 1998, the ICD-9-CM Coordination and Maintenance Committee created code 99.10 (Injection or infusion of thrombolytic agent) in order to be able to uniquely identify the administration of thrombolytic agents. Studies have shown that tPA can be effective in reducing the amount of damage the brain sustains during an ischemic stroke, which is caused by blood clots that block blood flow to the brain. The use of tPA is approved for patients who have blood clots in the brain, but not for patients who have a bleeding or hemorrhagic stroke. Thrombolytic therapy has been shown to be most effective when used within the first 3 hours after the onset of a stroke, and it is contraindicated in hemorrhagic stroke. The presence or absence of code 99.10 does not currently influence DRG assignment. Since code 99.10 became effective, we have been monitoring the DRGs and cases in which this code can be found, particularly with respect to cardiac and stroke DRGs.

Last year, we met with representatives from several hospital stroke centers who recommended modification of the existing stroke DRGs 14 (Intracranial Hemorrhage or Cerebral Infarction) and 15 (Nonspecific CVA and Precerebral Occlusion Without Infarction) by using the administration of tPA as a proxy to identify patients who have severe strokes. The representatives stated that using tPA as a proxy for the more severely ill stroke patient would recognize the higher charges these cases generate because of their higher hospital resource utilization.

The stroke representatives made two suggestions concerning DRGs 14 and 15. First, they proposed modifying DRG 14 by renaming it ``Ischemic Stroke Treatment with a Reperfusion Agent,'' and including only those cases containing code 99.10. The remainder of stroke cases where the patient was not treated with a reperfusion agent would be included in DRG 15, which would be renamed ``Hemorrhagic Stroke or Ischemic Stroke without a Reperfusion Agent.'' Hemorrhagic stroke cases now found in DRG 14 that are not treated with a reperfusion agent would migrate to DRG 15.

The second suggestion was to leave DRGs 14 and 15 as they currently exist, and create a new DRG, with a recommended title ``Ischemic Stroke Treatment with a Reperfusion Agent.'' This suggested DRG would only include strokes caused by clots, not by hemorrhages, and would include the administration of tPA, identified by procedure code 99.10.

We have examined the MedPAR data for the cases in DRGs 14 and 15, and have divided the cases based on the presence of a principal diagnosis of hemorrhage or occlusive ischemia, and the presence of procedure code 99.10. The following table displays the results:

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[GRAPHIC] [TIFF OMITTED] TP04MY05.002

The above table shows that the average standardized charges for cases treated with a reperfusion agent are more than $16,000 and $10,000 higher than all other cases in DRGs 14 and 15, respectively. While these data suggest that patients treated with a reperfusion agent are more expensive than all other stroke patients, this conclusion is based on a small number of cases. At this time, we are not proposing a change to the stroke DRGs because of this concern. However, we believe it is possible that more patients are being treated with a reperfusion agent than indicated by our data because the presence of code 99.10 does not affect DRG assignment and may be underreported.

We invite public comment on the changes to DRGs 14 and 15 suggested by the hospital representatives. In addition, we are interested in public comment on the number of patients currently being treated with a reperfusion agent as well as the potential costs of these patients relative to others with strokes that are also included in DRGs 14 and 15. b. Unruptured Cerebral Aneurysms

In the FY 2004 IPPS final rule (68 FR 45353), we created DRG 528 (Intracranial Vascular Procedures With a Principal Diagnosis of Hemorrhage) in MDC 1. We received a comment at that time that suggested we create another DRG for intracranial vascular procedures for unruptured cerebral aneurysms. For the FY 2004 IPPS final rule (68 FR 45353) and the FY 2005 IPPS final rule (69 FR 48957), we evaluated the data for cases in the MedPAR file involving unruptured cerebral aneurysms assigned to DRG 1 (Craniotomy Age >17 With CC) and DRG 2 (Craniotomy Age >17 Without CC) and concluded that the average charges were consistent with those for other cases found in DRGs 1 and 2. Therefore, we did not propose a change to the DRG assignment for unruptured cerebral aneurysms.

We have reviewed the latest data for unruptured cerebral aneurysms cases. In our analysis of the FY 2004 MedPAR data, we found 1,136 unruptured cerebral aneurysm cases assigned to DRG 1 and 964 unruptured cerebral aneurysm cases assigned to DRG 2. Although the average charges for the unruptured cerebral aneurysm cases in DRG 1 ($53,455) and DRG 2 ($34,028) were slightly higher than the average charges for all cases in DRG 1 ($51,466) and DRG 2 ($30,346), we do not believe these differences are significant enough to warrant a change in these two DRGs at this time. Therefore, we are not proposing a change in the structure of these DRGs relating to unruptured cerebral aneurysm cases for FY 2006. 4. MDC 5 (Diseases and Disorders of the Circulatory System) a. Automatic Implantable Cardioverter/Defibrillator

As part of our annual review of DRGs, for FY 2006, we performed a review of cases in the FY 2004 MedPAR file involving the implantation of a defibrillator in the following DRGs:

DRG 515 (Cardiac Defibrillator Implant Without Cardiac Catheterization).

DRG 535 (Cardiac Defibrillator Implant With Cardiac Catheterization With Acute Myocardial Infarction, Heart Failure, or Shock).

DRG 536 (Cardiac Defibrillator Implant With Cardiac Catheterization Without Acute Myocardial Infarction, Heart Failure, or Shock).

While conducting our review, we noted that there had been considerable comments from hospital coders on code 37.26 (Cardiac electrophysiologic stimulation and recording studies (EPS)), which is included in these DRGs. These comments from hospital coders were directed at both CMS and the American Hospital Association. The procedure codes for these three DRGs describe the procedures that are considered to be a cardiac catheterization. Code 37.26 is classified as a cardiac catheterization within these DRGs. Therefore, the submission of code

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37.26 affects the DRG assignment for defibrillator cases and leads to the assignment of DRGs 535 or 536. When a cardiac catheterization is performed, the case is assigned to DRGs 535 or 536, depending on whether or not the patient also had an acute myocardial infarction, heart failure, or shock. The following chart shows the number of cases in each DRG, along with their average length of stay and average charges, found in the data:

[GRAPHIC] [TIFF OMITTED] TP04MY05.003

We have received a number of questions from hospital coders regarding the correct use of code 37.26. There is considerable confusion about whether or not code 37.26 should be reported when the procedure is performed as part of the defibrillator implantation. Currently, the ICD-9-CM instructs the coder not to report code 37.26 when a defibrillator is inserted. There is an inclusion term under the defibrillator code 37.94 (Implantation or replacement of automatic cardioverter/defibrillator, total system [AICD]) which states that EPS is included in code 37.94. We discussed modifying this instruction at the October 7-8, 2004 meeting of the ICD-9-CM Coordination and Maintenance Committee. We received a number of comments opposing a modification to the use of code 37.26 to also allow it to be reported with an AICD insertion. A report of this meeting can be found on the Web site: http://www.cms.hhs.gov/paymentsystem/icd9.

We performed an analysis of cases within DRGs 535 and 536 with cardiac catheterization and with and without code 37.26 and with code 37.26 only reported without cardiac catheterization and found the following:

[GRAPHIC] [TIFF OMITTED] TP04MY05.004

The data show that when code 37.26 is the only procedure reported from the list of cardiac catheterizations, the average charges and the average length of stay are considerably lower. For example, the average standardized charges for a defibrillator implant with only an EPS are $85,390.88 in DRG 536, while the average standardized charges for DRG 536 with a cardiac catheterization, but not an EPS, are $110,493.86. The average standardized charges for all cases in DRG 536 are $94,453.62. The data show similar findings for DRG 535, with lower lengths of stay and average charges when the only code reported from the cardiac catheterization list is an EPS. When we also consider that there may be some coding problems in the use of code 37.26, we believe it is appropriate to propose a modification to these DRGs.

Data reflected in the chart above show that the average standardized charges for DRG 515 were $83,659.76. These average charges are closer to those in DRG 536 with code 37.26 and without any other cardiac catheterization code reported. While the cases in DRG 535 with code 37.26 and without a cardiac catheterization have higher average charges than the average charges for cases in DRG 515, these cases have much lower average charges than the average charges for overall cases in DRG 535. For these reasons, we are proposing to remove code 37.26 from the list of cardiac catheterizations for DRGs 535 and 536. If a defibrillator is implanted and an EPS is performed with no other type of cardiac catheterization, the case would be assigned to DRG 515.

CMS issued a National Coverage Determination for implantable cardioverter defibrillators, effective January 27, 2005, that expands coverage and requires, in certain cases, that patient data be reported when the defibrillator is implanted for the clinical indication of primary prevention of sudden cardiac death. The submission of data on patients receiving an implantable cardioverter defibrillator for primary prevention to a data collection system is needed for the determination that the implantable cardioverter

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defibrillator is reasonable and necessary and for quality improvement. These data will be made available in some form to providers and practitioners to inform their decisions, monitor performance quality, and benchmark and identify best practices. We made a temporary registry available for use when the policy became effective and used the Quality Net Exchange for data submission because Medicare-participating hospitals already use the Exchange to report data.

We intend to transition from the temporary registry using the Quality Net Exchange to a more sophisticated follow-on registry that will have the ability to collect longitudinal data. Some providers have suggested that CMS increase reimbursement for implantable cardioverter defibrillators to compensate the provider for reporting data. ICD data reporting includes elements of patient demographics, clinical characteristics and indications, medications, provider information, and complications. Since these data elements are commonly found in patient medical records, it is CMS' expectation that these data are readily available to the individuals abstracting and reporting data. Therefore, we believe that increased reimbursement is not needed at this time. b. Coronary Artery Stents

In the FY 2005 IPPS final rule (69 FR 48971 through 48974), we addressed two comments from industry representatives about the DRG assignments for coronary artery stents. These commenters had expressed concern about whether the reimbursement for stents is adequate, especially for insertion of multiple stents. They also expressed concern about whether the current DRG structure represents the most clinically coherent classification of stent cases.

The current DRG structure incorporates stent cases into the following two pairs of DRGs, depending on whether bare metal or drug- eluting stents are used and whether acute myocardial infarction (AMI) is present:

DRG 516 (Percutaneous Cardiovascular Procedures with AMI).

DRG 517 (Percutaneous Cardiovascular Procedures with Nondrug-Eluting Stent without AMI).

DRG 526 (Percutaneous Cardiovascular Procedures with Drug- Eluting Stent with AMI).

DRG 527 (Percutaneous Cardiovascular Procedures with Drug- Eluting Stent without AMI).

The commenters presented two recommendations for refinement and restructuring of the current coronary stent DRGs. One of the recommendations involved restructuring these DRGs to create two additional stent DRGs that are closely patterned after the existing pairs, and would reflect insertion of multiple stents with and without AMI. The commenters recommended incorporating either stenting code 36.06 (Insertion of nondrug-eluting coronary artery stent(s)) or code 36.07 (Insertion of drug-eluting coronary artery stent(s)) when they are reported along with code 36.05 (Multiple vessel percutaneous transluminal coronary angioplasty [PTCA] or coronary atherectomy performed during the same operation, with or without mention of thrombolytic agent). The commenter's first concern was that hospitals may be steering patients toward coronary artery bypass graft surgery in place of stenting in order to avoid significant financial losses due to what it considered the inadequate reimbursement for inserting multiple stents.

In our response to comments in the FY 2005 IPPS final rule, we indicated that it was premature to act on this recommendation because the current coding structure for coronary artery stents cannot distinguish cases in which multiple stents are inserted from those in which only a single stent is inserted. Current codes are able to identify performance of PTCA in more than one vessel by use of code 36.05. However, while this code indicates that PTCA was performed in more than one vessel, its use does not reflect the exact number of procedures performed or the exact number of vessels treated. Similarly, when codes 36.06 and 36.07 are used, they document the insertion of at least one stent. However, these stenting codes do not identify how many stents were inserted in a procedure, nor distinguish insertion of a single stent from insertion of multiple stents. Even the use of one of the stenting codes in conjunction with multiple-PTCA code 36.05 does not distinguish insertion of a single stent from multiple stents. The use of code 36.05 in conjunction with code 36.06 or code 36.07 indicates only performance of PTCA in more than one vessel, along with insertion of at least one stent. The precise numbers of PTCA-treated vessels, the number of vessels into which stents were inserted, and the total number of stents inserted in all treated vessels cannot be determined. Therefore, the capabilities of the current coding structure do not permit the distinction between single and multiple vessel stenting that would be required under the recommended restructuring of the coronary stent DRGs.

We agree that the DRG classification of cases involving coronary stents must be clinically coherent and provide for adequate reimbursement, including those cases requiring multiple stents. For this reason, we created four new ICD-9-CM codes identifying multiple stent insertion (codes 00.45, 00.46, 00.47, and 00.48) and four new codes identifying multiple vessel treatment (codes 00.40, 00.41, 00.42, and 00.43) at the October 7, 2004 ICD-9-CM Coordination and Maintenance Committee Meeting. These eight new codes can be found in Table 6B of this proposed rule. We have worked closely with the coronary stent industry and the clinical community to identify the most logical code structure to identify new codes for both multiple vessel and multiple stent use. Effective October 1, 2005, code 36.05 will be deleted and the eight new codes will be used in its place. Coders are encouraged to use as many codes as necessary to describe each case, using one code to describe the angioplasty or atherectomy, and one code each for the number of vessels treated and the number of stents inserted. Coders are encouraged to record codes accurately, as these data will potentially be the basis for future DRG restructuring. While we agree that use of multiple vessel and stent codes will provide useful information in the future on hospital costs associated with percutaneous coronary procedures, we believe it remains premature to proceed with a restructuring of the current coronary stent DRGs on the basis of the number of vessels treated or the number of stents inserted, or both, in the absence of data reflecting use of this new coding structure.

The commenter's second recommendation was that we distinguish ``complex'' from ``noncomplex'' cases in the stent DRGs by expanding the higher weighted DRGs (516 and 526) to include conditions other than AMI. The commenter recommended recognizing certain comorbid and complicating conditions, including hypertensive renal failure, congestive heart failure, diabetes, arteriosclerotic cardiovascular disease, cerebrovascular disease, and certain procedures such as multiple vessel angioplasty or atherectomy (as evidenced by the presence of procedure code 36.05), as indicators of complex cases for this purpose. Specifically, the commenters recommended replacing the current structure with the following four DRGs:

Recommended restructured DRG 516 (Complex percutaneous

[[Page 23319]]

cardiovascular procedures with non-drug-eluting stents).

Recommended restructured DRG 517 (Noncomplex percutaneous cardiovascular procedures with non-drug-eluting stents).

Recommended restructured DRG 526 (Complex percutaneous cardiovascular procedures with drug-eluting stents).

Recommended restructured DRG 527 (Noncomplex percutaneous cardiovascular procedures with drug-eluting stents).

The commenter argued that this structure would provide an improvement in both clinical and resource coherence over the current structure that classifies cases according to the type of stent inserted and the presence or absence of AMI alone, without considering other complicating conditions. The commenter also presented an analysis, based on previous MedPAR data, that evaluated charges and lengths of stay for cases with expected high resource use and reclassified cases into its recommended new structure of paired ``complex'' and ``noncomplex'' DRGs. The commenter's analysis showed some evidence of clinical and resource coherence in the recommended DRG structure. However, we did not adopt the proposal in the FY 2005 IPPS final rule. First, the data presented by the commenter still represented preliminary experience under a relatively new DRG structure. Second, the analysis did not reveal significant gains in resource coherence compared to existing DRGs for stenting cases. Therefore, we were reluctant to adopt this approach because of comments and concern about whether the overall level of payment in the coronary stent DRGs was adequate. However, we indicated that this issue deserved further study and consideration, and that we would conduct an analysis of this recommendation and other approaches to restructuring these DRGs with updated data in the FY 2006 proposed rule.

This year, we have analyzed the MedPAR data to determine the impact of certain secondary diagnoses or complicating conditions on the four DRGs cited above. Specifically, we examined the data in DRGs 516, 517, 526, and 527, based on the presence of coronary stents (codes 36.06 and 36.07) and the following additional diagnoses:

Congestive heart failure (represented by codes 398.91 (Rheumatic heart failure (congestive)), 402.01 (Hypertensive heart disease, malignant, with heart failure), 402.11, (Hypertensive heart disease, benign, with heart failure), 402.91 (Hypertensive heart disease, unspecified, with heart failure), 404.01 (Hypertensive heart and renal disease, malignant, with heart failure), 404.03 (Hypertensive heart and renal disease, malignant, with heart failure and renal failure), 404.11 (Hypertensive heart and renal disease, benign, with heart failure), 404.13 (Hypertensive heart and renal disease, benign, with heart failure and renal failure), 404.91 (Hypertensive heart and renal disease, unspecified, with heart failure), 404.93 (Hypertensive heart and renal disease, unspecified, with heart failure and renal failure), 428.0 (Congestive heart failure, unspecified), and 428.1 (Left heart failure)).

Arteriosclerotic cardiovascular disease (represented by code 429.2 (Cardiovascular disease, unspecified)).

Cerebrovascular disease (represented by codes 430.0 (Subarachnoid hemorrhage), 431.0 (Intracerebral hemorrhage), 432.0 (Nontraumatic extradural hemorrhage), 432.1, Subdural hemorrhage, 432.9, (Unspecified intracranial hemorrhage), 433.01 (Occlusion and stenosis of basilar artery, with cerebral infarction), 433.11 (Occlusion and stenosis of carotid artery, with cerebral infarction), 433.21 (Occlusion and stenosis of vertebral artery, with cerebral infarction), 433.31 (Occlusion and stenosis of multiple and bilateral precerebral arteries, with cerebral infarction), 433.81 (Occlusion and stenosis of other specified precerebral artery, with cerebral infarction), 434.01 (Cerebral thrombosis with cerebral infarction), 434.11 (Cerebral embolism with cerebral infarction), 434.91 (Cerebral artery occlusion with cerebral infarction, unspecified), 436.0 (Acute, but ill-defined, cerebrovascular disease)).

Secondary diagnosis of acute myocardial infarction (represented by codes 410.01 (Acute myocardial infarction of anterolateral wall, initial episode of care), 410.11 (Acute myocardial infarction of other anterior wall, initial episode of care), 410.21 (Acute myocardial infarction of inferolateral wall, initial episode of care), 410.31 (Acute myocardial infarction of inferoposterior wall, initial episode of care), 410.41 (Acute myocardial infarction of other inferior wall, initial episode of care), 410.51 (Acute myocardial infarction of other lateral wall, initial episode of care), 410.61 (True posterior wall infarction, initial episode of care), 410.71 (Subendocardial infarction, initial episode of care), 410.81 (Acute myocardial infarction of other specified sites, initial episode of care), 410.91 (Acute myocardial infarction of unspecified site, initial episode of care)).

Renal failure (represented by codes 403.01 (Hypertensive renal disease, malignant, with renal failure), 403.11 (Hypertensive renal disease, benign, with renal failure), 403.91 (Hypertensive renal disease, unspecified, with renal failure), 585.0 (Chronic renal failure), V42.0 (Organ or tissue replaced by transplant, kidney), V45.1 (Renal dialysis status), V56.0 (Extracorporeal dialysis), V56.1 (Fitting and adjustment of extracorporeal dialysis catheter), V56.2 (Fitting and adjustment of peritoneal dialysis catheter)). Any renal failure with congestive heart failure will be captured in the 404.xx codes listed above.

We reviewed the cases in the four coronary stent DRGs and found that most of the additional or ``complicated'' cases did, in fact, have higher average charges in most instances. However, these results could potentially be duplicated for many DRGs, or sets of DRGs, within the PPS structure. That is, cases with selected complicating factors will tend to have higher average lengths of stay and average charges than cases without those complicating factors. Since cases with the selected complicating factors necessarily contain sicker patients, longer lengths of stay and higher average charges are to be expected. For example, cases in which patients with a cardiac condition also have renal failure are quite likely to consume higher resources than patients only with a cardiac condition. In addition, selectively recognizing the recommended secondary diagnoses or complicating conditions raises some issues related to the logic and structural integrity of the DRG system. Generally, we have taken into account the higher costs of cases with complications by maintaining a general list of comorbidities and complications (the CC) list), and, where appropriate, distinguishing pairs of DRGs by ``with and without CCs.'' (This system also specifies exclusions from each pair, to account for cases where a condition on the CC list is an expected and normal constituent of the diagnoses reflected in the paired DRGs.) In order to maintain the basic DRG body-system structure, we have not employed special lists of procedures and diagnoses from one MDC to make determinations about the structure of DRGs in another MDC. The recommended restructuring of the coronary stent DRGs is inconsistent with this principle and may create a new precedent of selecting specific comorbidities and complications to restructure DRGs. For example, the

[[Page 23320]]

presence of code 403.11 (Hypertensive renal disease, malignant, with renal failure) may distinguish cases with higher average charges, but the same argument could be raised for many other procedures across other MDCs.

Rather than establishing such a precedent, we are proposing to restructure the coronary stent DRGs on the basis of the standard CC list to differentiate cases that require greater resources. We believe this list to be more inclusive of true comorbid or complicating conditions than selection of specific secondary diagnosis codes. Therefore, restructuring these DRGs on this basis would result in a logical arrangement of cases with regard to both clinical coherence and resource consumption. We have compared the existing CC list with the list of the codes recommended by the commenter as secondary diagnoses. All of the recommended codes already appear on the CC list except for codes 429.2, 432.9, V56.1, and V56.2. Code 429.2 represents a very vague diagnosis (arteriosclerotic cardiovascular disease (ASCVD)). Code 432.9 represents a nonspecific principal diagnosis that is rejected by the MCE when reported as the principal diagnosis. Codes V56.1 and V56.2 describe conditions relating to dialysis for renal failure. Therefore, we believe that our proposal to utilize the existing CC list would encompass most of the cases on the recommended list, as well as other cases with additional CCs requiring additional resources. We have examined the MedPAR data for the cases in the coronary stent DRGs, distinguishing cases that include CCs and those that do not. The following table displays the results:

[GRAPHIC] [TIFF OMITTED] TP04MY05.005

The data show a clear differentiation in average charges between the cases in DRG 516 and 526 ``with CC'' and those ``without CC.'' Therefore, the data suggest that a ``with and without CC'' split in DRG 516 and 526 is warranted. At the same time, the data do not show such a clear differentiation, in either average charges or lengths of stay, among the cases in DRGs 517 and 527.

Therefore, we are proposing to delete DRGs 516 and 526, and to substitute four new DRGs in their place. These new DRGs would be patterned after existing DRGs 516 and 526, except that they would be split based on the presence or absence of a secondary diagnosis on the existing CC list. Specifically, we are proposing to create DRG 547 (Percutaneous Cardiovascular Procedure with AMI with CC), DRG 548 (Percutaneous Cardiovascular Procedure with AMI without CC), DRG 549 (Percutaneous Cardiovascular Procedure with Drug-Eluting Stent with AMI with CC), and DRG 550 (Percutaneous Cardiovascular Procedure with Drug- Eluting Stent with AMI without CC). As we noted above, the MedPAR data do not support restructuring DRGs 517 and 527 based on the presence or absence of a CC. Therefore, we are proposing to retain these two DRGs in their current forms. We believe this revised structure will result in a more inclusive and comprehensive array of cases within MDC 5 without selectively recognizing certain secondary diagnoses as ``complex.''

While we are proposing some restructuring of the coronary stent DRGs for FY 2006, it is important to note that we will continue to monitor and analyze clinical and resource trends in this area. For example, we have found indications in the current data that treatment may be moving toward use of drug-eluting stents, and away from use of bare metal stents. Specifically, cases in DRGs 516 and 517, which utilize bare metal stents, comprise only 44.4 percent, or less than half, of the cases in the four coronary stent DRGs in the MedPAR data we analyzed. As use of drug-eluting stents becomes the standard of treatment, we may consider over time whether to dispense with the distinction between these stents and the older bare metal stent technology in the structure of the coronary stent DRGs. In addition, we will continue to consider whether the structure of these DRGs ought to reflect differences in the number of vessels treated or the number of stents inserted, or both. As we discussed above, a new coding structure capable of identifying multiple vessel treatment and the insertion of multiple stents will go into effect on October 1, 2005. It remains premature to restructure the coronary stent DRGs on the basis of the number of vessels treated or the number of stents inserted, or both, until data reflecting the use of these new codes become available. However, we will analyze those data when they become available in order to determine whether a restructuring based on multiple vessel treatment or insertion of multiple stents, or both, is warranted. Our proposal to restructure two of the current coronary stent DRGs into paired ``with and without CC'' DRGs for FY 2006 does not preclude proposals in subsequent years to restructure the coronary stent DRGs in one or both of these ways.

[[Page 23321]]

c. Insertion of Left Atrial Appendage Device

Atrial fibrillation is a common heart rhythm disorder that can lead to a cardiovascular blood clot formation leading to increased risk of stroke. According to product literature, nearly all strokes are from embolic clots arising in the left atrial appendage of the heart: an appendage for which there is no useful function. Standard therapy uses anticoagulation drugs. However, these drugs may be contraindicated in certain patients and may cause complications such as bleeding. The underlying concept behind the left atrial appendage device is to block off the left atrial appendage, so that the blood clots formed therein cannot travel to other sites in the vascular system. The device is implanted using a percutaneous catheter procedure under fluoroscopy through the femoral vein. Implantation is performed in a hospital catheterization laboratory using standard transseptal technique, with the patient generally under local anesthesia. The procedure takes approximately 1 hour, and most patients stay overnight in the hospital.

In the FY 2005 IPPS final rule (69 FR 48978, August 11, 2004), we discussed the DRG assignment of new ICD-9-CM procedure code 37.90 (Insertion of left atrial appendage device) for clinical trials, effective for discharges occurring on or after October 1, 2004, to DRG 518 (Percutaneous Cardiovascular Procedure without Coronary Artery Stent or Acute Myocardial Infarction)). In that final rule, we addressed the DRG assignment of procedure code 37.90 in response to a comment from a manufacturer who suggested that placement of the code in DRG 108 (Other Cardiothoracic Procedures) was more representative of the complexity of the procedure than placement in DRG 518. The manufacturer indicated that the suggested placement of procedure code 37.90 in DRG 108 was justified because another percutaneous procedure, described by ICD-9-CM procedure code 35.52 (Repair of atrial septal defect with prosthesis, closed technique), was assigned to DRG 108. As we indicated in the FY 2005 final rule (69 FR 48978), this comment prompted us to examine data in the FY 2003 MedPAR file for cases of code 35.52 assigned to DRG 108 and DRG 518 in comparison to all cases assigned to DRG 108. We found the following:

[GRAPHIC] [TIFF OMITTED] TP04MY05.006

Therefore, we concluded that procedure code 35.52 showed a decided similarity to the cases found in DRG 518, not DRG 108. At that time, we determined that we would analyze the cases for both clinical coherence and charge data as part of the IPPS FY 2006 process of identifying the most appropriate DRG assignment for procedure code 35.52.

We have now examined data from the FY 2004 MedPAR file and found results for cases assigned to DRG 108 and DRG 518 that are similar to last year's findings as indicated in the chart below:

[GRAPHIC] [TIFF OMITTED] TP04MY05.007

From this comparison, we found that when an atrial septal defect is percutaneously repaired, and procedure code 35.52 is the only code reported in DRG 108, there is a significant discrepancy in both the average charges and the average length of stay between the cases with procedure code 35.52 reported in DRG 108 and the total cases in DRG 108. The total cases in DRG 108 have average charges of $51,744 greater than the 872 cases in DRG 108 reporting procedure code 35.52 as the only procedure. The total cases in DRG 108 also have an average length of stay of 7.39 days greater than the average length of stay for cases in DRG 108 with procedure code 35.52 reported. In comparison, the total cases in DRG 518 have average charges of only $1,988 lower than the cases in DRG 108 with only procedure code 35.52 reported. In addition, the length of stay in total cases in DRG 518 is more closely related to cases in DRG 108 with only procedure code 35.52 reported.

Based on our analysis of these data, we are proposing to move procedure code 35.52 out of DRG 108 and place it in DRG 518. We believe that this proposal would result in a more coherent group of cases in DRG 518 that reflect all percutaneous procedures. d. External Heart Assist System Implant

In the August 1, 2002, final rule (67 FR 49989), we attempted to clinically and financially align ventricular assist device (VAD) procedures by creating DRG 525 (Heart Assist System Implant). We also noted that cases in which a heart transplant also occurred during the same hospitalization episode would continue to be assigned to DRG 103 (Heart Transplant).

After further data review during the next 2 years, we decided to realign the

[[Page 23322]]

DRGs containing VAD codes for FY 2005. In the August 11, 2004 final rule (69 FR 48927), we announced changes to DRG 103, DRG 104 (Cardiac Valve and Other Major Cardiothoracic Procedure with Cardiac Catheterization), DRG 105 (Cardiac Valve and Other Major Cardiothoracic Procedures Without Cardiac Catheterization), and DRG 525.

In summary, these changes included--

Moving code 37.66 (Insertion of implantable heart assist system) out of DRG 525 and into DRG 103.

Renaming DRG 525 as ``Other Heart Assist System Implant.''

Moving code 37.62 (Insertion of non-implantable heart assist system) out of DRGs 104 and 105 and back into DRG 525.

DRG 525 currently consists of any principal diagnosis in MDC 5, plus the following surgical procedure codes:

37.52, Implantation of total replacement heart system *.

37.53, Replacement or repair of thoracic unit of total replacement heart system *.

37.54, Replacement or repair of other implantable component of total replacement heart system *.

37.62, Insertion of non-implantable heart assist system.

37.63, Repair of heart assist system.

37.65, Implant of external heart assist system.

* These codes represent noncovered services for Medicare beneficiaries. However, it is our longstanding practice to assign every code in the ICD-9-CM classification to a DRG. Therefore, they have been assigned to DRG 525.

Since that decision, we have been encouraged by a manufacturer to reevaluate DRG 525 for FY 2006. The manufacturer requested that we again review the data surrounding cases reporting code 37.65 and has suggested moving these cases into DRG 103. The manufacturer pointed out the following: Code 37.65 describes the implantation of an external heart assist system and is currently approved by the FDA as a bridge- to-recovery device. From the standpoint of clinical status, the patients in DRG 103 and receiving an external heart assist system are similar because their native hearts cannot support circulation, and absent a heart transplant, a mechanical pump is needed for patient survival. The surgical procedures for implantation of both an internal VAD and an external VAD are very similar. However, the external heart assist system (code 37.65) is a less expensive device than the implantable heart assist system (code 37.66). The manufacturer suggested that the payment differential between DRGs 103 and 525 is an incentive to choose the higher paying device, and asserted that only a subset of patients receiving an implantable heart assist system are best served by this device. The manufacturer also suggested that the initial use of the least expensive therapeutically appropriate device yields both the best clinical outcomes and the lowest total system costs.

We note that, under the DRG system, our intent is to create payments that are reflective of the average resources required to treat a particular case. Our goal is that physicians and hospitals should make treatment decisions based on the clinical needs of the patient and not financial incentives.

When we reviewed the FY 2004 MedPAR data, we were able to demonstrate the following comparisons:

[GRAPHIC] [TIFF OMITTED] TP04MY05.008

The above table shows that the 37.8 percent of cases in DRG 525 that reported code 37.65 have average charges that are nearly $33,000 higher than the average charges for all cases in the DRG. However, the average charges for the subset of cases with code 37.65 in DRG 525 ($206,497) are more than $107,086 lower than the average charges for all cases in DRG 103 ($313,583). Furthermore, the average length of stay for the subset of patients in DRG 525 receiving an external heart assist system was 9.26 days compared to 37.5 days for the 633 cases in DRG 103.

We note that the analysis above presents the difference in average charges, not costs. Because hospitals' charges are higher than costs, the difference in hospital costs will be less than the figures shown here. Moving cases containing code 37.65 from DRG 525 to DRG 103 would have two consequences. The cases in DRG 103 reporting code 37.65 would be appreciably overreimbursed, which would be inconsistent with our goal of coherent reimbursement structure within the DRGs. In addition, the relative weight of DRG 103 would decrease by moving the less resource-intensive external heart procedures into the same DRG with the more expensive heart transplant cases. The net effect would be an underpayment for heart transplant cases. Alternatively, we also reconsidered our position on moving the insertion of an implantable heart assist system (code 37.66) back into

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DRG 525. However, as shown in the FY 2005 IPPS final rule (69 FR 48929), the resource costs associated with caring for a patient receiving an implantable heart assist system are far more similar to those cases receiving a heart transplant in DRG 103 than they are to cases in DRG 525. For these reasons, we are not proposing to make any changes to the structure of either DRG 103 or DRG 525 in this proposed rule. e. Carotid Artery Stent

Stroke is the third leading cause of death in the United States and the leading cause of serious, long-term disability. Approximately 70 percent of all strokes occur in people age 65 and older. The carotid artery, located in the neck, is the principal artery supplying the head and neck with blood. Accumulation of plaque in the carotid artery can lead to stroke either by decreasing the blood flow to the brain or by having plaque break free and lodge in the brain or in other arteries to the head. The percutaneous transluminal angioplasty (PTA) procedure involves inflating a balloon-like device in the narrowed section of the carotid artery to reopen the vessel. A carotid stent is then deployed in the artery to prevent the vessel from closing or restenosing. A distal filter device (embolic protection device) may also be present, which is intended to prevent pieces of plaque from entering the bloodstream.

Effective July 1, 2001, Medicare covers PTA of the carotid artery concurrent with carotid stent placement when furnished in accordance with the FDA-approved protocols governing Category B Investigational Device Exemption (IDE) clinical trials. PTA of the carotid artery, when provided solely for the purpose of carotid artery dilation concurrent with carotid stent placement, is considered to be a reasonable and necessary service only when provided in the context of such clinical trials and, therefore, is considered a covered service for the purposes of these trials. Performance of PTA in the carotid artery when used to treat obstructive lesions outside of approved protocols governing Category B IDE clinical trials remains a noncovered service.

At the April 1, 2004 ICD-9-CM Coordination and Maintenance Committee meeting, we discussed creation of a new code or codes to identify carotid artery stenting, along with a concomitant percutaneous angioplasty or atherectomy (PTA) code for delivery of the stent(s). This subject was addressed in response to the need to identify carotid artery stenting for use in clinical trials in the upcoming fiscal year. Public comment confirmed the need for specific codes for this procedure. We established codes for carotid artery stenting procedures effective October 1, 2004, for patients who are enrolled in an FDA- approved clinical trial and are using on-label FDA approved stents and embolic protection devices.

New procedure codes 00.61 (Percutaneous angioplasty or atherectomy of precerebral (extracranial vessel(s)) and 00.63 (Percutaneous insertion of carotid artery stent(s)) were published in Table 6B, New Procedure Codes in the FY 2005 IPPS final rule (69 FR 49624).

Procedure code 00.61 was assigned to four MDCs and seven DRGs. The most likely scenario is that in which cases are assigned to MDC 1 (Diseases and Disorders of the Nervous System in DRGs 533 (Extracranial Procedures with CC) and 534 (Extracranial Procedures without CC). Cases may also be assigned to MDC 5 (Diseases and Disorders of the Circulatory System), MDC 21 (Injuries, Poisoning, and Toxic Effects of Drugs), and MDC 24 (Multiple Significant Trauma). Other less likely DRG assignments can be found in Table 6B in the Addendum to the FY 2005 IPPS final rule (69 FR 49624).

In the FY 2005 final rule, we indicated that we would continue to monitor DRGs 533 and 534 and procedure code 00.61 in combination with procedure code 00.63 in upcoming annual DRG reviews. For this proposed rule, we are using proxy codes to evaluate the costs and DRG assignments for carotid artery stenting because codes 00.61 and 00.63 were only approved for use beginning October 1, 2004, and because MedPAR data for this period are not yet available. We used procedure code 39.50 (Angioplasty or atherectomy of other noncoronary vessel(s)) in combination with procedure code 39.90 (Insertion of nondrug-eluting peripheral vessel stent(s)) in DRGs 533 and 534 as the proxy codes for coronary artery stenting. For this evaluation, we used principal diagnosis code 433.10 (Occlusion and stenosis of carotid artery, without mention of cerebral infarction) because this diagnosis most closely reflects the clinical trial criteria.

The following chart shows our findings:

[GRAPHIC] [TIFF OMITTED] TP04MY05.009

The patients receiving a carotid stent (codes 39.50 and 39.90) represented 3.5 percent of all cases in DRG 534. On average, patients receiving a carotid stent had slightly shorter average lengths of stay than other patients in DRGs 533 and 534. While the average charges for patients receiving a carotid artery stent were higher than for other patients in DRG 534, in our view, the small number of cases and the magnitude of the difference in average charges are not sufficient to justify a change in the DRGs.

Because we have a paucity of data for the carotid stent device and its insertion, and no data utilizing procedure codes 00.61 and 00.63 in a clinical trial setting, we believe it is premature to revise the DRG structure at this time. We expect to revisit this analysis once data become available on the new codes for carotid artery stents.

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f. Extracorporeal Membrane Oxygenation (ECMO)

Extracorporeal membrane oxygenation (ECMO) is a procedure to create a closed chest, heart-lung bypass system by insertion of vascular catheters. Patients receiving this procedure require mechanical ventilation. ECMO is performed for a small number of severely ill patients who are at high risk of dying without this procedure. Most often it is done for neonates with persistent pulmonary hypertension and respiratory failure for whom other treatments have failed, certain severely ill neonates receiving major cardiac procedures or diaphragmatic hernia repair, and certain older children and adults, most of whom are receiving major cardiac procedures.

We received several letters from institutions that perform ECMO. The commenters stated that, in the CMS GROUPER logic, this procedure has little or no impact on the DRG assignment in the newborn, pediatric, and adult population. According to these letters, patients receiving ECMO are highly resource intensive and should have a unique DRG that reflects the costs of these resources. The commenters recommended the creation of a new DRG for ECMO with a DRG weight equal to or greater than the DRG weight for tracheostomy.

ECMO is assigned to procedure code 39.65 (Extracorporeal membrane oxygenation). This code is classified as an O.R. procedure and is assigned to DRG 104 (Cardiac Valve and Other Major Cardiothoracic Procedure With Cardiac Catheterization) and DRG 105 (Cardiac Valve and Other Major Cardiothoracic Procedure Without Cardiac Catheterization). When ECMO is performed with other O.R. procedures, the case is assigned to the higher weighted DRG. For example, when ECMO and a tracheostomy are performed during the same admission, the case would be assigned to DRG 541 (Tracheostomy with Mechanical Ventilation 96+ Hours or Principal Diagnosis Except Face, Mouth, and Neck Diagnoses With Major O.R.).

We note that the primary focus of updates to the Medicare DRG classification system is changes relating to the Medicare patient population, not the pediatric patient population. Because ECMO is primarily a pediatric procedure and rarely performed in an adult population, we have few cases in our data to use to evaluate resource costs. We are aware that other insurers sometimes use Medicare's rates to make payments. We advise private insurers to make appropriate modifications to our payment system when it is being used for children or other patients who are not generally found in the Medicare population.

To evaluate the appropriateness of payment under the current DRG assignment, we have reviewed the FY 2004 MedPAR data and found 78 ECMO cases in 13 DRGs. The following table illustrates the results of our findings:

[GRAPHIC] [TIFF OMITTED] TP04MY05.010

The average charges for all ECMO cases were approximately $258,821, and the average length of stay was approximately 20.7 days. The average charges for the ECMO cases are closer to the average charges for DRG 541 ($273,656) than to the average charges of DRG 104 ($147,766) and DRG 105 ($131,700). Of the 78 ECMO cases, 14 cases are already assigned to DRG 541. We believe that the data indicate that DRG 541 would be a more appropriate DRG assignment for cases where ECMO is performed. We further note that under the All Payer DRG System used in New York State, cases involving ECMO are assigned to the tracheostomy DRG. Thus, the assignment of ECMO cases to the tracheostomy DRG for Medicare would be similar to how these cases are grouped in another DRG system. For these reasons, we are proposing to reassign ECMO cases reporting code 39.65 to DRG 541. We are also proposing to change the title of DRG 541 to: ``ECMO or Tracheostomy With Mechanical Ventilation 96+ Hours or Principal Diagnosis Except Face, Mouth and Neck Diagnoses With Major O.R.'' 5. MDC 6 (Diseases and Disorders of the Digestive System): Artificial Anal Sphincter

In the FY 2003 IPPS final rule (67 FR 50242), we created two new codes for procedures involving an artificial anal sphincter, effective for discharges occurring on or after October 1, 2002: code 49.75 (Implantation or revision of artificial anal sphincter) is used to identify cases involving implantation or revision of an artificial anal sphincter and code 49.76 (Removal of artificial anal sphincter) is used to identify cases involving the removal of the device. In Table 6B of that final rule, we assigned both codes to one of four MDCs, based on principal diagnosis, and one of six DRGs within those MDCs: MDC 6 (Diseases and Disorders of the Digestive System), DRGs 157 and 158 (Anal and Stomal Procedures With and Without CC, respectively); MDC 9 (Diseases and Disorders of the Skin, Subcutaneous Tissue and Breast), DRG 267 (Perianal and Pilonidal Procedures); MDC 21 (Injuries, Poisonings, and Toxic Effects of Drugs), DRGs 442 and 443 (Other O.R. Procedures for Injuries With and without CC, respectively); and MDC 24 (Multiple Significant Trauma), DRG 486 (Other O.R. Procedures for Multiple Significant Trauma).

In the FY 2004 IPPS final rule (68 FR 45372), we discussed the assignment of these codes in response to a request we had received to consider reassignment of these two codes to different MDCs and DRGs. The requester believed that the average charges ($44,000) for these codes warranted reassignment. In the FY 2004 IPPS final rule, we stated that we did not have sufficient MedPAR data available on the reporting of codes 49.75 and 49.76 to make a determination on

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DRG reassignment of these codes. We agreed that, if warranted, we would give further consideration to the DRG assignments of these codes because it is our customary practice to review DRG assignment(s) for newly created codes to determine clinical coherence and similar resource consumption after we have had the opportunity to collect MedPAR data on utilization, average lengths of stay, average charges, and distribution throughout the system. In the FY 2005 IPPS final rule, we reviewed the FY 2003 MedPAR data for the presence of codes 49.75 and 49.76 and determined that these procedures were not a clinical match with the other procedures in DRGs 157 and 158. Therefore, for FY 2005, we moved procedure codes 49.75 and 49.76 out of DRGs 157 and 158 and into DRGs 146 and 147 (Rectal Resection With and Without CC, respectively). This change had the effect of doubling the payment for the cases with procedure codes 49.75 and 49.76 assigned to DRGs 146 and 147 based on increases in the relative weights. One commenter had suggested that we create a new DRG for ``Complex Anal/Rectal Procedure with Implant.'' However, we noted that the DRG structure is a system of averages and is based on groups of patients with similar characteristics. At that time, we indicated that we would continue to monitor procedure codes 49.75 and 49.76 and the DRGs to which they are assigned.

For this FY 2006 proposed rule, we reviewed the FY 2004 MedPAR data for the presence of codes 49.75 and 49.76. We found that these two procedures are still of low incidence. Among the six possible DRG assignments, we found a total of 18 cases reported with codes 49.75 and 49.76 for the implant, revision, or removal of the artificial anal sphincter. We found 13 of these cases in DRGs 146 and 147 (compared to 12,558 total cases in these DRGs), and the remaining 5 cases in DRGs 442 and 443 (compared to 19,701 total cases in these DRGs).

We believe the number of cases with codes 49.75 and 49.76 in these DRGs is too low to provide meaningful data of statistical significance. Therefore, we are not proposing any further changes to the DRGs for these procedures at this time. Neither are we proposing to change the structure of DRGs 146 or 147 at this time. 6. MDC 8 (Diseases and Disorders of the Musculoskeletal System and Connective Tissue) a. Hip and Knee Replacements

Orthopedic surgeons representing the American Association of Orthopaedic Surgeons (AAOS) requested that we subdivide DRG 209 (Major Joint and Limb Reattachment Procedures of Lower Extremity) in MDC 8 by creating a new DRG for revision of lower joint procedures. The AAOS made a presentation at the October 7-8, 2004 meeting of the ICD-9-CM Coordination and Maintenance Committee meeting. A summary report of this meeting can be found at the CMS Web site: http://www.cms.hhs.gov/paymentsystems/icd9/. We also received written comments on this

request.

The AAOS surgeons stated that cases involving patients who require a revision of a prior replacement of a knee or hip require significantly more resources than cases in which patients receive an initial joint replacement. They pointed out that total joint replacement is one of the most commonly performed and successful operations in orthopedic surgery. The surgeons mentioned that, in 2002, over 300,000 hip replacement and 350,000 knee replacement procedures were performed in the United States. They also pointed out that these procedures are a frequent reason for Medicare hospitalization. The surgeons stated that total joint replacements have been shown to be highly cost-effective procedures, resulting in dramatic improvements in quality of life for patients suffering from disabling arthritic conditions involving the hip or knee. In addition, they reported that the medical literature indicates success rates of greater than 90 percent for implant survivorship, reduction in pain, and improvement in function at a 10-year to 15-year followup. However, despite these excellent results with primary total joint replacement, factors related to implant longevity and evolving patient demographics have led to an increase in the volume of revision total joint procedures performed in the United States over the past decade.

Total hip replacement is an operation that is intended to reduce pain and restore function in the hip joint by replacing the arthritic hip joint with a prosthetic ball and socket joint. The prosthetic hip joint consists of a metal alloy femoral component with a modular femoral head made of either metal or ceramic (the ``ball'') that articulates with a metal acetabular component with a modular liner made of either metal, ceramic, or high-density polyethylene (the ``socket'').

The AAOS surgeons stated that in a normal knee, four ligaments help hold the bones in place so that the joint works properly. When a knee becomes arthritic, these ligaments can become scarred or damaged. During knee replacement surgery, some of these ligaments, as well as the joint surfaces, are substituted or replaced by the new artificial prostheses. Two types of fixation are used to hold the prostheses in place. Cemented designs use polymethyl methacrylate to hold the prostheses in place. Cementless designs rely on bone growing into the surface of the implant for fixation.

The surgeons stated that all hip and knee replacements have an articular bearing surface that is subject to wear (the acetabular bearing surface in the hip and the tibial bearing surface in the knee). Traditionally, these bearing surfaces have been made of metal-on-metal or metal-on-polyethylene, although newer materials (both metals and ceramics) have been used more recently. Earlier hip and knee implant designs had nonmodular bearing surfaces, but later designs included modular articular bearing surfaces to reduce inventory and potentially simplify revision surgery. Wear of the articular bearing surface occurs over time and has been found to be related to many factors, including the age and activity level of the patient. In some cases, wear of the articular bearing surface can produce significant debris particles that can cause peri-prosthetic bone resorption (also known and osteolysis) and mechanical loosening of the prosthesis. Wear of the bearing surface can also lead to instability or prosthetic dislocation, or both, and is a common cause of revision hip or knee replacement surgery.

Depending on the cause of failure of the hip replacement, the type of implants used in the previous surgery, the amount and quality of the patient's remaining bone stock, and factors related to the patient's overall health and anatomy, revision hip replacement surgery can be relatively straightforward or extremely complex. Revision hip replacement can involve replacing any part or all of the implant, including the femoral or acetabular components, and the bearing surface (the femoral head and acetabular liner), and may involve major reconstruction of the bones and soft tissues around the hip. All of these procedures differ significantly in their clinical indications, outcomes, and resource intensity.

The AAOS surgeons provided the following summary of the types of

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revision knee replacement procedures: Among revision knee replacement procedures, patients who underwent complete revision of all components had longer operative times, higher complication rates, longer lengths of stay, and significantly higher resource utilization, according to studies conducted by the AAOS. Revision of the isolated modular tibial insert component was the next most resource-intensive procedure, and primary total knee replacement was the least resource-intensive of all the procedures studied.

Isolated Modular Tibial Insert Exchange. Isolated removal and exchange of the modular tibial bearing surface involves replacing the modular polyethylene bearing surface without removing the femoral, tibial, or patellar components of the prosthetic joint. Common indications for this procedure include wear of the polyethylene bearing surface or instability (for example, looseness) of the prosthetic knee joint. Patient recovery times are much shorter with this procedure than with removal and exchange of either the tibial, femoral, or patellar components.

Revision of the Tibial Component. Revision of the tibial component involves removal and exchange of the entire tibial component, including both the metal base plate and the modular polyethylene bearing surface. Common indications for tibial component revision are wear of the modular bearing surface, aseptic loosening (often associated with osteolysis), or infection. Depending on the amount of associated bone loss and the integrity of the ligaments around the knee, tibial component revision may require the use of specialized implants with stems that extend into the tibial canal and/or the use of metal augments or bone graft to fill bony defects.

Revision of the Femoral Component. Revision of the femoral component involves removal and exchange of the metal implant that covers the end of the thigh-bone (the distal femur). Common indications for femoral component revision are aseptic loosening with or without associated osteolysis/bone loss, or infection. Similar to tibial revision, femoral component revision that is associated with extensive bone loss often involves the use of specialized implants with stems that extend into the femoral canal and/or the use of metal augments or bone graft to fill bony defects.

Revision of the Patellar Component. Complications related to the patella-femoral joint are one of the most common indications for revision knee replacement surgery. Early patellar implant designs had a metal backing covered by high-density polyethylene; these implants were associated with a high rate of failure due to fracture of the relatively thin polyethylene bearing surface. Other common reasons for isolated patellar component revision include poor tracking of the patella in the femoral groove leading to wear and breakage of the implant, fracture of the patella with or without loosening of the patellar implant, rupture of the quadriceps or patellar tendon, and infection.

Revision of All Components (Tibial, Femoral, and Patellar). The most common type of revision knee replacement procedure is a complete total knee revision. A complete revision of all implants is more common in knee replacements than hip replacements because the components of an artificial knee are not compatible across vendors or types of prostheses. Therefore, even if only one of the implants is loose or broken, a complete revision of all components is often required in order to ensure that the implants are compatible. Complete total knee revision often involves extensive surgical approaches, including osteotomizing (for example, cutting) the tibia bone in order to adequately expose the knee joint and gain access to the implants. These procedures often involve extensive bone loss, requiring reconstruction with specialized implants with long stems and metal augments or bone graft to fill bony defects. Depending on the status of the ligaments in the knee, complete total knee revision at times requires implantation of a highly constrained or ``hinged'' knee replacement in order to ensure stability of the knee joint.

Reimplantation from previous resection or cement spacer. In cases of deep infection of a prosthetic knee, removal of the implants with implantation of an antibiotic-impregnated cement spacer, followed by 6 weeks of intravenous antibiotics is often required in order to clear the infection. Revision knee replacement from an antibiotic impregnated cement spacer often involves complex bony reconstruction due to extensive bone loss that occurs as a result of the infection and removal of the often well-fixed implants. As noted above, the clinical outcomes following revision from a spacer are often poor due to limited functional capacity while the spacer is in place, prolonged periods of protected weight bearing (following reconstruction of extensive bony defects), and the possibility of chronic infection.

The surgeons stated that the current ICD-9-CM codes did not adequately capture the complex nature of revisions of hip and knee replacements. Currently, code 81.53 (Revision of hip replacement) captures all ``partial'' and ``total'' revision hip replacement procedures. Code 81.55 (Revision of knee replacement) captures all revision knee replacement procedures. These two codes currently capture a wide variety of procedures that differ in their clinical indications, resource intensity, and clinical outcomes.

An AAOS representative made a presentation at the October 7-8, 2004 ICD-9-CM Coordination and Maintenance Committee. Based on the comments received at the October 7-8, 2004 meeting and subsequent written comments, new ICD-9-CM procedure codes were developed to better capture the variety of ways that revision of hip and knee replacements can be performed: codes 00.70 through 00.73 and code 81.53 for revisions of hip replacements and codes 00.80 through 00.84 and code 81.55 for revisions of knee replacements. These new and revised procedure codes, which will be effective on October 1, 2005, can be found in Table 6B and Table 6F of this proposed rule. The commenters stated that claims data using these new and specific codes should provide improved data on these procedures for future DRG modifications.

However, the commenters requested that CMS consider DRG modifications based on current data using the existing revision codes. The commenters reported on a recently completed study comparing detailed hospital resource utilization and clinical characteristics in over 10,000 primary and revision hip and knee replacement procedures at 3 high volume institutions: The Massachusetts General Hospital, the Mayo Clinic, and the University of California at San Francisco. The purpose of this study was to evaluate differences in clinical outcomes and resource utilization among patients who underwent different types of primary and revision hip or knee replacement procedures. The study found significant differences in operative time, complication rates, hospital length of stay, discharge disposition, and resource utilization among patients who underwent different types of revision hip or knee replacement procedures.

Among revision hip replacement procedures, patients who underwent both femoral and acetabular component revision had longer operative times, higher complication rates, longer lengths of stay, significantly higher resource utilization, and were more likely to be discharged to a subacute care facility. Isolated femoral

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component revision was the next most resource-intensive procedure, followed by isolated acetabular revision. Primary hip replacement was the least resource intensive of all the procedures studied. Similarly, among revision knee replacement procedures, patients who underwent complete revision of all components had longer operative times, higher complication rates, longer lengths of stay, and significantly higher resource utilization. Revision of one component was the next most resource-intensive procedure. Primary total knee replacement was the least resource intensive of all the procedures studied.

In addition, the commenters indicated that the data showed that extensive bone loss around the implants and the presence of a peri- prosthetic fracture were the most significant predictors of higher resource utilization among all revision hip and knee replacement procedures, even when controlling for other significant patient and procedural characteristics.

For this proposed rule, we examined data in the FY 2004 MedPAR file on the current hip replacement procedures (codes 81.51, 81.52, 81.53) as well as the replacements and revisions of knee replacement procedures (codes 81.54 and 81.55) in DRG 209. We found that revisions were significantly more resource intensive than the original hip and knee replacements. We found average charges for revisions of hip and knee replacements were approximately $7,000 higher than average charges for the original joint replacements, as shown in the following charts. The average charges for revisions of hip replacements were 21 percent higher than the average charges for initial hip replacements. The average charges for revisions of knee replacements were 25 percent higher than for initial knee replacements.

[GRAPHIC] [TIFF OMITTED] TP04MY05.011

We note that there were no cases in DRG 209 for reattachment of the foot, lower leg, or thigh (codes 84.29, 84.27, and 84.28).

To address the higher resource costs associated with hip and knee revisions relative to the initial joint replacement procedure, we are proposing to delete DRG 209, create a proposed new DRG 544 (Major Joint Replacement or Reattachment of Lower Extremity), and create a proposed new DRG 545 (Revision of Hip or Knee Replacement).

We are proposing to assign the following codes to the new proposed DRG 544:

81.51, Total hip replacement.

81.52, Partial hip replacement.

81.54, Total knee replacement.

81.56, Total ankle replacement.

84.26, Foot reattachment.

84.27, Lower leg/ankle reattach.

84.28, Thigh reattachment.

We are proposing to assign the following codes to the proposed new DRG 545:

00.70, Revision of hip replacement, both acetabular and femoral components.

00.71, Revision of hip replacement, acetabular component.

00.72, Revision of hip replacement, femoral component.

00.73, Revision of hip replacement, acetabular liner and/ or femoral head only.

00.80, Revision of knee replacement, total (all components).

00.81, Revision of knee replacement, tibial component.

00.82, Revision of knee replacement, femoral component.

00.83, Revision of knee replacement, patellar component.

00.84, Revision of knee replacement, tibial insert (liner).

81.53, Revision of hip replacement, not otherwise specified.

81.55, Revision of knee replacement, not otherwise specified.

We agree with the commenters and the AAOS that the creation of a new DRG for revisions of hip and knee replacements should resolve payment issues for hospitals that perform the more difficult revisions of joint replacements. In addition, as stated earlier, we have worked with the orthopedic community to develop new procedure codes that better capture data on the types of revisions of hip and knee replacements. These new codes will be implemented on October 1, 2005. Once we receive claims data using these new codes, we will review data to determine if additional DRG modifications are needed. This effort may include assigning some of the revision codes, such as 00.83 and 00.84 to a separate DRG. As stated earlier, the AAOS has found that some of the procedures may not be as resource intensive. Therefore, the AAOS has requested that CMS closely examine data from the use of the new codes and consider future revisions. b. Kyphoplasty

In the FY 2005 IPPS final rule (69 FR 48938), we discussed the creation of new codes for vertebroplasty (81.65) and kyphoplasty (81.66), which went into effect on October 1, 2004. Prior to October 1, 2004, both of these surgical procedures were assigned to code 78.49 (Other repair or plastic operation on bone). For FY 2005, we assigned these codes to DRGs 233 and 234 (Other Musculoskeletal System and Connective Tissue O.R. Procedure With and Without CC, respectively) in MDC 8 (Table 6B of the FY 2005 final rule). (In the FY 2005 IPPS final rule (69 FR 48938), we indicated that new codes 81.65 and 81.66 were assigned to DRGs 223 and 234. We made a typographical error when indicating that these codes were assigned to DRG 223. Codes 81.65 and 81.66 have been assigned to DRGs

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233 and 234.) Last year, we received comments opposing the assignment of code 81.66 to DRGs 233 and 234. The commenters supported the creation of the codes for kyphoplasty and vertebroplasty but recommended that code 81.66 be assigned to DRGs 497 and 498 (Spinal Fusion Except Cervical With and Without CC, respectively). The commenters stated that kyphoplasty requires special inflatable bone tamps and bone cement and is a significantly more resource intensive procedure than vertebroplasty. The commenters further stated that, while kyphoplasty involves internal fixation of the spinal fracture and restoration of vertebral heights, vertebroplasty involves only fixation. The commenters indicated that hospital costs for kyphoplasty procedures are more similar to resources used in a spinal fusion.

We stated in the FY 2005 IPPS final rule that we did not have data in the MedPAR file on kyphoplasty and vertebroplasty. Prior to October 1, 2004, both procedures were assigned in code 78.49, which was assigned to DRGs 233 and 234 in MDC 8. We stated that we would continue to review this area as part of our annual review of MedPAR data. While we do not have separate data for kyphoplasty because code 81.66 was not established until October 1, 2004, for this proposed rule, we did examine data on code 78.49, which includes both kyphoplasty and vertebroplasty procedures reported in DRGs 233 and 234. The following chart illustrates our findings:

[GRAPHIC] [TIFF OMITTED] TP04MY05.012

We do not believe these data findings support moving cases represented by code 78.49 out of DRGs 233 and 234. While we cannot distinguish cases that are kyphoplasty from cases that are vertebroplasty, cases represented by code 78.49 have lower charges than do other cases within DRGs 233 and 234. Therefore, we are not proposing to change the DRG assignment of code 81.66 to DRGs 233 and 234 at this time. However, once specific charge data are available, we will consider whether further changes are warranted. c. Multiple Level Spinal Fusion

On October 1, 2003, the following ICD-9-CM codes were created to identify the number of levels of vertebra fused during a spinal fusion procedure:

81.62, Fusion or refusion of 2-3 vertebrae.

81.63, Fusion or refusion of 4-8 vertebrae.

81.64, Fusion or refusion of 9 or more vertebrae.

Prior to the creation of these codes, we received a comment recommending the establishment of new DRGs that would be differentiated based on the number of vertebrae fused. In the FY 2005 IPPS final rule (69 FR 48936), we stated that we did not yet have any reported cases utilizing these multiple level spinal fusion codes. We stated that we would wait until sufficient data were available prior to making a final determination on whether to create separate DRGs based on the number of vertebrae fused. We also stated that spinal fusion surgery was an area undergoing rapid changes.

Effective October 1, 2004, we created a series of codes that describe a new type of spinal surgery, spinal disc replacement. Our medical advisors describe these procedures as a more conservative approach for back pain than the spinal fusion surgical procedure. These codes are as follows:

84.60, Insertion of spinal disc prosthesis, not otherwise specified.

84.61, Insertion of partial spinal disc prosthesis, cervical.

84.62, Insertion of total spinal disc prosthesis, cervical.

84.63, Insertion of spinal disc prosthesis, thoracic.

84.64, Insertion of partial spinal disc prosthesis, lumbosacral.

84.65, Insertion of total spinal disc prosthesis, lumbosacral.

84.66, Revision or replacement of artificial spinal disc prosthesis, cervical.

84.67, Revision or replacement of artificial spinal disc prosthesis, thoracic.

84.68, Revision or replacement of artificial spinal disc prosthesis, lumbosacral.

84.69, Revision or replacement of artificial spinal disc prosthesis, not otherwise specified.

We also created the following two codes effective October 1, 2004, for these new types of spinal surgery that are also a more conservative approach to back pain than is spinal fusion:

81.65 Vertebroplasty.

81.66 Kyphoplasty.

We do not yet have data in the MedPAR file on these new types of procedures. Therefore, we cannot yet determine what effect these new types of procedures will have on the frequency of spinal fusion procedures.

However, we do have data in the MedPAR file on multiple level spinal procedures for analysis for this year's proposed rule. We examined data in the FY 2004 MedPAR file on spinal fusion cases in the following DRGs:

DRG 496 (Combined Anterior/Posterior Spinal Fusion).

DRG 497 (Spinal Fusion Except Cervical With CC).

DRG 498 (Spinal Fusion Except Cervical Without CC).

DRG 519 (Cervical Spinal Fusion With CC).

DRG 520 (Cervical Spinal Fusion Without CC).

Multiple level spinal fusion is captured by code 81.63 (Fusion or refusion of 4-8 vertebrae) and code 81.64 (Fusion or refusion of 9 or more vertebrae). Code 81.62 includes the fusion of 2-3 vertebrae and is not considered a multiple level spinal fusion. Orthopedic surgeons stated at the October 7-8, 2004 ICD-9-CM Coordination and Maintenance Committee meeting that the most simple and common type of spinal fusion involves fusing either 2 or 3 vertebrae. These surgeons stated that there was not

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a significant difference in resource utilization for cases involving the fusion of 2 versus 3 vertebrae. For this reason, the orthopedic surgeons recommended that fusion of 2 and 3 vertebrae be grouped into one ICD-9-CM code.

We reviewed the Medicare charge data to determine whether the number of vertebrae fused or specific diagnoses have an effect on average length of stay and resource use for a patient. We found that, while fusing 4 or more levels of the spine results in a small increase in the average length of stay and a somewhat larger increase in average charges for spinal fusion patients, an even greater impact was made by the presence of a principal diagnosis of curvature of the spine or malignancy. The following list of diagnoses describes conditions that have a significant impact on resource use for spinal fusion patients:

170.2, Malignant neoplasm of vertebral column, excluding sacrum and coccyx.

198.5, Secondary malignant neoplasm of bone and bone marrow.

732.0, Juvenile osteochondrosis of spine.

733.13, Pathologic fracture of vertebrae.

737.0, Adolescent postural kyphosis.

737.10, Kyphosis (acquired) (postural).

737.11, Kyphosis due to radiation.

737.12, Kyphosis, postlaminectomy.

737.19, Kyphosis (acquired), other.

737.20, Lordosis (acquired) (postural).

737.21, Lordosis, postlaminectomy

737.22, Other postsurgical lordosis.

737.29, Lordosis (acquired), other.

737.30, Scoliosis [and kyphoscoliosis], idiopathic.

737.31, Resolving infantile idiopathic scoliosis.

737.32, Progressive infantile idiopathic scoliosis.

737.33, Scoliosis due to radiation.

737.34, Thoracogenic scoliosis.

737.39, Other kyphoscoliosis and scoliosis.

737.40, Curvature of spine, unspecified.

737.41, Curvature of spine associated with other conditions, kyphosis.

737.42, Curvature of spine associated with other conditions, lordosis.

737.43, Curvature of spine associated with other conditions, scoliosis.

737.8, Other curvatures of spine.

737.9, Unspecified curvature of spine.

754.2, Congenital scoliosis.

756.51, Osteogenesis imperfecta.

The majority of fusion patients with these diagnoses were in DRGs 497 and 498. The chart below reflects our findings. We also include in the chart statistics for cases in DRGs 497 and 498 with spinal fusion of 4 or more vertebrae and cases with a principal diagnosis of curvature of the spine or bone malignancy.

[GRAPHIC] [TIFF OMITTED] TP04MY05.013

Thus, these diagnoses result in a significant increase in resource use. While the fusing of 4 or more vertebrae resulted in average charges of $77,352, the impact of a principal diagnosis of curvature of the spine or bone malignancy was substantially greater with average charges of $95,315.

Based on this analysis, we are proposing to create a new DRG for noncervical spinal fusions with a principal diagnosis of curvature of the spine and malignancies. The proposed new DRG would be: proposed new DRG 546 (Spinal Fusions Except Cervical With Principal Diagnosis of Curvature of the Spine or Malignancy). Cases included in this proposed new DRG would include all noncervical spinal fusions previously assigned to DRGs 497 and 498 that have a principal diagnosis of curvature of the spine or malignancy and would include the following codes listed above: 170.2, 198.5, 732.0, 733.13, 737.0, 737.10, 737.11, 737.12, 737.19, 737.20, 737.21, 737.22, 737.29, 737.30, 737.31, 737.32, 737.33, 737.34, 737.39, 737.40, 737.41, 737.42, 737.43, 737.8, 737.9, 754.2, and 756.51. The proposed DRG 546 would not include cases currently assigned to DRGs 496, 519, or 520 that have a principal diagnosis of curvature of the spine or malignancy. The structure of DRGs 496, 519, and 520 would remain the same.

As part of our meeting with the AAOS on DRG 209 in February 2005 (discussed under section II.B.6.a. of this preamble), the AAOS offered to work with CMS to analyze clinical issues and make revisions to the spinal fusion DRGs (DRGs 496 through 498 and 519 and 520). At this time, we are limiting our proposed changes to the spinal fusion DRGs for FY 2006 to the creation of the proposed DRG 546 discussed above. However, we look forward to working with the AAOS to obtain its clinical recommendations concerning our proposed changes and potential additional modifications to the spinal fusion DRGs. We are also soliciting comments from the public on our proposed changes and how to incorporate new types of spinal procedures such as kyphoplasty and spinal disc prostheses into the spinal fusion DRGs. 7. MDC 18 (Infectious and Parasitic Diseases (Systemic or Unspecified Sites)): Severe Sepsis

As we did for FY 2005, we received a request to consider the creation of a separate DRG for the diagnosis of severe sepsis for FY 2006. Severe sepsis is described by ICD-9-CM code 995.92 (Systemic inflammatory response syndrome due to infection with organ dysfunction). Patients admitted with sepsis currently are assigned to DRG 416 (Septicemia Age > 17) and DRG 417

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(Septicemia Age 0-17) in MDC 18 (Infectious and Parasitic Diseases, Systemic or Unspecified Sites). The commenter requested that all cases in which severe sepsis is present on admission, as well as those cases in which it develops after admission (which are currently classified elsewhere), be included in this new DRG. We addressed this issue in the FY 2005 IPPS final rule (69 FR 48975). As indicated last year, we do not feel the current clinical definition of severe sepsis is specific enough to identify a meaningful cohort of patients in terms of clinical coherence and resource utilization to warrant a separate DRG. Sepsis is found across hundreds of medical and surgical DRGs, and the term ``organ dysfunction'' implicates numerous currently existing diagnosis codes. While we recognize that Medicare beneficiaries with severe sepsis are quite ill and require extensive hospital resources, we do not believe that they can be identified adequately to justify removing them from all of the other DRGs in which they appear. We are not proposing a new DRG for severe sepsis at this time. 8. MDC 20 (Alcohol/Drug Use and Alcohol/Drug Induced Organic Mental Disorders): Drug-Induced Dementia

In the FY 2005 IPPS final rule (69 FR 48939, August 11, 2004), we discussed a request that CMS modify DRGs 521 through 523 by removing the principal diagnosis code 292.82 (Drug-induced dementia) from these alcohol and drug abuse DRGs. These DRGs are as follows:

DRG 521 (Alcohol/Drug Abuse or Dependence With CC).

DRG 522 (Alcohol/Drug Abuse or Dependence With Rehabilitation Therapy Without CC).

DRG 523 (Alcohol/Drug Abuse or Dependence Without Rehabilitation Therapy Without CC).

The commenter indicated that a patient who has a drug-induced dementia should not be classified to an alcohol/drug DRG. However, the commenter did not propose a new DRG assignment for code 292.82. Our medical advisors evaluated the request and determined that the most appropriate DRG classification for a patient with drug-induced dementia was within MDC 20. The medical advisors indicated that because the dementia is drug induced, it is appropriately classified to DRGs 521 through 523 in MDC 20. Therefore, we did not propose a new DRG classification for the principal diagnosis code 292.82.

In the FY 2005 IPPS final rule, we addressed a comment from an organization representing hospital coders that disagreed with our decision to keep code 292.82 in DRGs 521 through 523. The commenter stated that DRGs 521 through 523 are described as alcohol/drug abuse and dependence DRGs, and that drug-induced dementia can be caused by an adverse effect of a prescribed medication or a poisoning. The commenter did not believe that assignment to DRGs 521 through 523 was appropriate if the drug-induced dementia is due to one of these events and the patient is not alcohol or drug dependent. The commenter recommended that admissions for drug-induced dementia be classified to DRGs 521 through 523 only if there is a secondary diagnosis indicating alcohol/ drug abuse or dependence.

The commenter recommended that drug-induced dementia that is due to the adverse effect of a drug or poisoning be classified to the same DRGs as other types of dementia, such as DRG 429 (Organic Disturbances and Mental Retardation). The commenter believed that when drug-induced dementia is caused by a poisoning, either accidental or intentional, the appropriate poisoning code would be sequenced as the principal diagnosis and, therefore, these cases would likely already be assigned to DRGs 449 and 450 (Poisoning and Toxic Effects of Drugs, Age Greater than 17, With and Without CC, respectively) and DRG 451 (Poisoning and Toxic Effects of Drugs, Age 0-17). The commenter stated that these would be the appropriate DRG assignments for drug-induced dementia due to a poisoning. We received a similar comment from a hospital organization.

In the FY 2005 IPPS final rule, we acknowledged that the commenters raised additional issues surrounding the DRG assignment for code 292.82 that should be considered. The commenters provided alternatives for DRG assignment based on sequencing of the principal diagnosis and reporting of additional secondary diagnoses. We recognized that patients may develop drug-induced dementia from drugs that are prescribed, as well as from drugs that are not prescribed. However, because dementia develops as a result of use of a drug, we believed the current DRG assignment to DRGs 521 through 523 remained appropriate. Some commenters have agreed with the current DRG assignment of code 292.82 since the dementia was caused by use of a drug. We agree that if either accidental or intentional poisoning caused the drug-induced dementia, the appropriate poisoning code should be sequenced as the principal diagnosis. As one commenter stated, these cases would be assigned to DRGs 449 through 451. We encouraged hospitals to examine the coding for these types of cases to determine if there were any coding or sequencing errors. As suggested by the commenter, if code 292.82 were reported as a secondary diagnosis and not a principal diagnosis in cases of poisoning or adverse drug reactions, the number of cases on DRGs 521 through 523 would decline.

In the FY 2005 IPPS final rule, we agreed to analyze this area for FY 2006 and to look at the alternative DRG assignments suggested by the commenters. For this proposed rule, we examined data from the FY 2004 MedPAR file on cases in DRGs 521 through 523 with a principal diagnosis of code 292.82. We found that there were only 134 cases reported with the principal diagnosis code 292.82 in DRGs 521 through 523 without a diagnosis of drug and alcohol abuse. The average standardized charges for cases with a principal diagnosis of code 292.82 that did not have a secondary diagnosis of drug/alcohol abuse or dependence were $12,244.35, compared to the average standardized charges for all cases in DRG 521, which were $10,543.69. There were no cases in DRG 522 with a principal diagnosis of code 292.82. We found only 24 cases in DRG 523 with a principal diagnosis of code 292.82. Given the small number of cases in DRG 522 and 523, and the similarity in average standardized charges between those cases in DRG 521 with a principal diagnosis of code 292.82 and without a secondary diagnosis of drug/alcohol abuse or dependence to the overall average for all cases in the DRG, we do not believe the data suggest that a modification to DRGs 521 through 523 is warranted. Therefore, we are not proposing changes to the current structure of DRGs 521 through 523 for FY 2006. 9. Medicare Code Editor (MCE) Changes

(If you choose to comment on issues in this section, please include the caption ``Medicare Code Editor'' at the beginning of your comment.)

As explained under section II.B.1. of this preamble, the Medicare Code Editor (MCE) is a software program that detects and reports errors in the coding of Medicare claims data. Patient diagnoses, procedure(s), discharge status, and demographic information go into the Medicare claims processing systems and are subjected to a series of automated screens. The MCE screens are designed to identify cases that require further review before classification into a DRG.

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a. Newborn Age Edit

In the past, we have discussed and received comments concerning revision of the pediatric portions of the Medicare IPPS DRG classification system, that is, MDC 15 (Newborns and Other Neonates With Conditions Originating in the Perinatal Period). Most recently, we addressed these comments in both the FY 2005 proposed rule (69 FR 28210) and the FY 2005 IPPS final rule (69 FR 48938). In those rules, we indicated that we would be responsive to specific requests for updating MDC 15 on a limited, case-by-case basis.

We have recently received a request through the Open Door Forum to revise the MCE ``newborn age edit'' by removing over 100 codes located in Chapter 15 of ICD-9-CM that are identified as ``newborn'' codes. This request was made because these codes usually cause an edit or denial to be triggered when they are used on children greater than 1 year of age. However, the underlying issue with these particular edits is that other payers have adopted the CMS Medicare Code Editor in a wholesale manner, instead of adapting it for use in their own patient populations.

We acknowledge that Medicare DRGs are sometimes used to classify other patient groups. However, CMS' primary focus of updates to the Medicare DRG classification system is on changes relating to the Medicare patient population, not the pediatric or neonatal patient populations.

There are practical considerations regarding the assumption of a larger role for the Medicare DRG in the pediatric or neonatal areas, given the difference between the Medicare population and that of newborns and children. There are also challenges surrounding the development of DRG classification systems and applications appropriate to children. We do not have the clinical expertise to make decisions about these patients, and must rely on outside clinicians for advice. In addition, because newborns and other children are generally not eligible for Medicare, we must rely on outside data to make decisions. We recognize that there are evolving alternative classification systems for children and encourage payers to use the CMS MCE as a template while making modifications appropriate for pediatric patients.

Therefore, we would encourage those non-Medicare systems needing a more comprehensive pediatric system of edits to update their systems by choosing from other existing systems or programs that are currently in use. Because of our reluctance to assume expertise in the pediatric arena, we are not proposing to make the commenter's suggested changes to the MCE ``newborn age edit'' for FY 2006. b. Newborn Diagnoses Edit

Last year, in our changes to the MCE, we inadvertently added code 796.6 (Abnormal findings on neonatal screening) to both the MCE edit for ``Maternity Diagnoses--age 12 through 55'', and the MCE edit for ``Diagnoses Allowed for Females Only''. We are proposing to remove code 796.6 from these two edits and add it to the ``Newborn Diagnoses'' edit. c. Diagnoses Allowed for ``Males Only'' Edit

We have received a request to remove two codes from the ``Diagnoses Allowed for Males Only'' edit, related to androgen insensitivity syndrome (AIS). AIS is a new term for testicular feminization. Code 257.8 (Other testicular dysfunction) is used to describe individuals who, despite having XY chromosomes, develop as females with normal female genitalia and mammary glands. Testicles are present in the same general area as the ovaries, but are undescended and are at risk for development of testicular cancer, so are generally surgically removed. These individuals have been raised as females, and would continue to be considered female, despite their XY chromosome makeup. Therefore, as AIS is coded to 257.8, and has posed a problem associated with the gender edit, we are proposing to remove this code from the ``Males Only'' edit in the MCE.

A similar clinical scenario can occur with certain disorders that cause a defective biosynthesis of testicular androgen. This disorder is included in code 257.2 (Other testicular hypofunction). Therefore, we also are proposing to remove code 257.2 from the ``Male Only'' gender edit in the MCE. d. Tobacco Use Disorder Edit

We have become aware of the possible need to add code 305.1 (Tobacco use disorder) to the MCE in order to make admissions for tobacco use disorder a noncovered Medicare service when code 305.1 is reported as the principal diagnosis. On March 22, 2005, CMS published a final decision memorandum and related national coverage determination (NCD) on smoking cessation counseling services on its Web site: (http://www.cms.hhs.gov/ coverage/). Among other things, this NCD provides

that: ``Inpatient hospital stays with the principal diagnosis of 305.1, Tobacco Use Disorder, are not reasonable and necessary for the effective delivery of tobacco cessation counseling services. Therefore, we will not cover tobacco cessation services if tobacco cessation is the primary reason for the patient's hospital stay.'' Therefore, in order to maintain internal consistency with CMS programs and decisions, we are proposing to add code 305.1 to the MCE edit ``Questionable Admission-Principal Diagnosis Only'' in order to make tobacco use disorder a noncovered admission. e. Noncovered Procedure Edit

Effective October 1, 2004, CMS adopted the use of code 00.61 (Percutaneous angioplasty or atherectomey of precerebral (extracranial) vessel(s) (PTA)) and code 00.63 (Percutaneous insertion of carotid artery stent(s). Both codes are to be recorded to indicate the insertion of a carotid artery stent or stents. At the time of the creation of the codes, the coverage indication for carotid artery stenting was only for patients in a clinical trial setting, and diagnostic code V70.7 (Examination of participation in a clinical trial) was required for payment of these cases. However, effective October 12, 2004, Medicare covers PTA of the carotid artery concurrent with the placement of an FDA-approved carotid stent for an FDA-approved indication when furnished in accordance with FDA-approved protocols governing post-approval studies. Therefore, as the coverage indication has changed, we are proposing to remove codes 00.61, 00.63, and V70.7 from the MCE noncovered procedure edit. 10. Surgical Hierarchies

(If you choose to comment on issues in this section, please include the caption ``Surgical Hierarchy'' at the beginning of your comment.)

Some inpatient stays entail multiple surgical procedures, each one of which, occurring by itself, could result in assignment of the case to a different DRG within the MDC to which the principal diagnosis is assigned. Therefore, it is necessary to have a decision rule within the GROUPER by which these cases are assigned to a single DRG. The surgical hierarchy, an ordering of surgical classes from most resource-intensive to least resource-intensive, performs that function. Application of this hierarchy ensures that cases involving multiple surgical procedures are assigned to the DRG associated with the most resource- intensive surgical class.

Because the relative resource intensity of surgical classes can shift as a function of DRG reclassification and recalibrations, we reviewed the surgical

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hierarchy of each MDC, as we have for previous reclassifications and recalibrations, to determine if the ordering of classes coincides with the intensity of resource utilization.

A surgical class can be composed of one or more DRGs. For example, in MDC 11, the surgical class ``kidney transplant'' consists of a single DRG (DRG 302) and the class ``kidney, ureter and major bladder procedures'' consists of three DRGs (DRGs 303, 304, and 305). Consequently, in many cases, the surgical hierarchy has an impact on more than one DRG. The methodology for determining the most resource- intensive surgical class involves weighting the average resources for each DRG by frequency to determine the weighted average resources for each surgical class. For example, assume surgical class A includes DRGs 1 and 2 and surgical class B includes DRGs 3, 4, and 5. Assume also that the average charge of DRG 1 is higher than that of DRG 3, but the average charges of DRGs 4 and 5 are higher than the average charge of DRG 2. To determine whether surgical class A should be higher or lower than surgical class B in the surgical hierarchy, we would weight the average charge of each DRG in the class by frequency (that is, by the number of cases in the DRG) to determine average resource consumption for the surgical class. The surgical classes would then be ordered from the class with the highest average resource utilization to that with the lowest, with the exception of ``other O.R. procedures'' as discussed below.

This methodology may occasionally result in assignment of a case involving multiple procedures to the lower-weighted DRG (in the highest, most resource-intensive surgical class) of the available alternatives. However, given that the logic underlying the surgical hierarchy provides that the GROUPER search for the procedure in the most resource-intensive surgical class, in cases involving multiple procedures, this result is sometimes unavoidable.

We note that, notwithstanding the foregoing discussion, there are a few instances when a surgical class with a lower average charge is ordered above a surgical class with a higher average charge. For example, the ``other O.R. procedures'' surgical class is uniformly ordered last in the surgical hierarchy of each MDC in which it occurs, regardless of the fact that the average charge for the DRG or DRGs in that surgical class may be higher than that for other surgical classes in the MDC. The ``other O.R. procedures'' class is a group of procedures that are only infrequently related to the diagnoses in the MDC, but are still occasionally performed on patients in the MDC with these diagnoses. Therefore, assignment to these surgical classes should only occur if no other surgical class more closely related to the diagnoses in the MDC is appropriate.

A second example occurs when the difference between the average charges for two surgical classes is very small. We have found that small differences generally do not warrant reordering of the hierarchy because, as a result of reassigning cases on the basis of the hierarchy change, the average charges are likely to shift such that the higher- ordered surgical class has a lower average charge than the class ordered below it.

Based on the preliminary recalibration of the DRGs, we are proposing to revise the surgical hierarchy for MDC 5 (Diseases and Disorders of the Circulatory System) and MDC 8 (Diseases and Disorders of the Musculoskeletal System and Connective Tissue) as follows:

In MDC 5, we are proposing to reorder--

DRG 116 (Other Permanent Cardiac Pacemaker Implant) above DRG 549 (Percutaneous Cardiovascular Procedure With Drug-Eluting Stent With AMI With CC).

DRG 549 above DRG 550 (Percutaneous Cardiovascular Procedure With Drug-Eluting Stent With AMI Without CC).

DRG 550 above DRG 547 (Percutaneous Cardiovascular Procedure With AMI With CC).

DRG 547 above DRG 548 (Percutaneous Cardiovascular Procedure With AMI Without CC).

DRG 548 above DRG 527 (Percutaneous Cardiovascular Procedure With Drug-Eluting Stent Without AMI).

DRG 527 above DRG 517 (Percutaneous Cardiovascular Procedure With Non-Drug Eluting Stent Without AMI).

DRG 517 above DRG 518 (Percutaneous Cardiovascular Procedure Without Coronary Artery Stent or AMI).

DRG 518 above DRGs 478 and 479 (Other Vascular Procedures With and Without CC, respectively).

In MDC 8, we are proposing to reorder--

DRG 496 (Combined Anterior/Posterior Spinal Fusion) above DRG 546 (Spinal Fusion Except Cervical With Principal Diagnosis of Curvature of the Spine or Malignancy).

DRG 546 above DRGs 497 and 498 (Spinal Fusion Except Cervical With and Without CC, respectively).

DRG 217 (Wound Debridement and Skin Graft Except Hand, For Musculoskeletal and Connective Tissue Disease) above DRG 545 (Revision of Hip or Knee Replacement).

DRG 545 above DRG 544 (Major Joint Replacement or Reattachment).

DRG 544 above DRGs 519 and 520 (Cervical Spinal Fusion With and Without CC, respectively). 11. Refinement of Complications and Comorbidities (CC) List

(If you choose to comment on issues in this section, please include the caption ``CC List'' at the beginning of your comment.) a. Background

As indicated earlier in this preamble, under the IPPS DRG classification system, we have developed a standard list of diagnoses that are considered complications or comorbidities (CCs). Historically, we developed this list using physician panels that classified each diagnosis code based on whether the diagnosis, when present as a secondary condition, would be considered a substantial complication or comorbidity. A substantial complication or comorbidity was defined as a condition that, because of its presence with a specific principal diagnosis, would cause an increase in the length of stay by at least 1 day in at least 75 percent of the patients. b. Comprehensive Review of the CC List

In previous years, we have made changes to the standard list of CCs, either by adding new CCs or deleting CCs already on the list, but we have never conducted a comprehensive review of the list. There are currently 3,285 diagnosis codes on the CC list. There are 121-paired DRGs that are split on the presence or absence of a CC.

We have reviewed these paired DRGs and found that the majority of cases that are assigned to DRGs that have a CC split fall into the DRG with CC. While this fact is not new, we have found that a much higher proportion of cases are being grouped to the DRG with a CC than had occurred in the past. In our review of the DRGs included in Table 7b of the September 1, 1987 Federal Register rule (52 FR 33125), we found the following percentages of cases assigned a CC in those DRGs that had a CC split (DRG Definitions Manual, GROUPER Version 5.0 (1986 data)):

Cases with CC: 61.9 percent.

Cases without CC: 38.1 percent.

When we compared the above DRG 1986 data to the DRG 2004 data that were included in the DRGs Definitions Manual, GROUPER Version 22.0, we found the following:

Cases with CC: 79.9 percent.

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Cases without CC: 20.1 percent.

(We used DRGs Definitions Manual, GROUPER Version 5.0, for this analysis because prior versions of the DRGs Definitions Manual used age as a surrogate for a CC and the split was ``CC and/or age greater than 69''.)

The vast majority of patients being treated in inpatient settings have a CC as currently defined, and we believe that it is possible that the CC distinction has lost much of its ability to differentiate the resource needs of patients. The original definition used to develop the CC list (the presence of a CC would be expected to extend the length of stay of at least 75 percent of the patients who had the CC by at least one day) was used beginning in 1981 and has been part of the IPPS since its inception in 1983. There has been no substantive review of the CC list since its original development. In reviewing this issue, our clinical experts found several diseases that appear to be obvious candidates to be on the CC list, but currently are not:

[GRAPHIC] [TIFF OMITTED] TP04MY05.014

Conversely, our medical experts believe the following conditions are examples of common conditions that are on the CC list, but are not likely to lead to higher treatment costs when present as a secondary diagnosis:

[GRAPHIC] [TIFF OMITTED] TP04MY05.015

We note that the above conditions are examples only of why we believe the CC list needs a comprehensive review. In addition to this review, we note that these conditions may be treated differently under several DRG systems currently in use. For instance, ICD-9-CM code 414.12 (Dissection of coronary artery) is listed as a ``Major CC'' under the All Patient (AP) DRGs, GROUPER Version 21.0 and an ``Extreme'' CC under the All Patient Refined (APR) DRGs, GROUPER Version 20.0, but is not listed as a CC at all in GROUPER Version 22.0 of the DRGs Definitions Manual used by Medicare. Similarly, ICD-9-CM code 424.0 (Mitral valve disorder) is a CC under GROUPER Version 22.0 of the DRGs Definitions Manual for Medicare's DRG system, a minor CC under the GROUPER Version 20.0 of the APR-DRGs, and not a CC at all under GROUPER Version 21.0 of the AP-DRGs.

Given the long period of time that has elapsed since the original CC list was developed, the incremental nature of changes to it, and changes in the way inpatient care is delivered, we are planning a comprehensive and systematic review of the CC list for the IPPS rule for FY 2007. As part of this process, we plan to consider revising the standard for determining when a condition is a CC. For instance, we may use an alternative to classifying a condition as a CC based on how it affects the length of stay of a case. Similar to other aspects of the DRG system, we may consider the effect of a specific secondary diagnosis on the charges or costs of a case to evaluate whether to include the condition on the CC list. Using a statistical algorithm, we may classify each diagnosis based on its effect on hospital charges (or costs) relative to other cases when present as a secondary diagnosis to obtain better information on when a particular condition is likely to increase hospital costs. For example, Code 293.84 (Anxiety disorder in conditions classified elsewhere), which is currently listed as a CC, might be removed from the CC list if analysis of the data do not support the fact that it represents a significant increase in resource utilization, and a code such as 359.4 (Toxic myopathy), which is currently not listed as a CC, could be added to the CC list if the data support it. In addition to using hospital charge data as a basis for a review, we would expect to supplement the process with review by our medical experts. Further, we may also consider doing a comparison of the Medicare DRG CC list with other DRG systems such as the AP-DRGs and the APR-DRGs to determine how the same secondary diagnoses are treated under these systems.

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By performing a comprehensive review of the CC list, we expect to revise the DRG classification system to better reflect resource utilization and remove conditions from the CC list that only have a marginal impact on a hospital's costs. We believe that a comprehensive review of the CC list would be consistent with MedPAC's recommendation that we improve the DRG system to better recognize severity. We will provide more detail about how we expect to undertake this analysis in the future, and any changes to the CC list will only be adopted after a notice and comment rulemaking that fully explains the methodology we plan to use in conducting this review. We encourage comment at this time regarding possible ways that more meaningful indicators of clinical severity and their implications for resource use can be incorporated into our comprehensive review and possible restructuring of the CC list. c. CC Exclusions List for FY 2006

In the September 1, 1987 final notice (52 FR 33143) concerning changes to the DRG classification system, we modified the GROUPER logic so that certain diagnoses included on the standard list of CCs would not be considered valid CCs in combination with a particular principal diagnosis. We created the CC Exclusions List for the following reasons: (1) to preclude coding of CCs for closely related conditions; (2) to preclude duplicative or inconsistent coding from being treated as CCs; and (3) to ensure that cases are appropriately classified between the complicated and uncomplicated DRGs in a pair. As we indicated above, we developed this list of diagnoses, using physician panels, to include those diagnoses that, when present as a secondary condition, would be considered a substantial complication or comorbidity. In previous years, we have made changes to the list of CCs, either by adding new CCs or deleting CCs already on the list. At this time, we are not proposing to delete any of the diagnosis codes on the CC list for FY 2006.

In the May 19, 1987 proposed notice (52 FR 18877) and the September 1, 1987 final notice (52 FR 33154), we explained that the excluded secondary diagnoses were established using the following five principles:

Chronic and acute manifestations of the same condition should not be considered CCs for one another.

Specific and nonspecific (that is, not otherwise specified (NOS)) diagnosis codes for the same condition should not be considered CCs for one another.

Codes for the same condition that cannot coexist, such as partial/total, unilateral/bilateral, obstructed/unobstructed, and benign/malignant, should not be considered CCs for one another.

Codes for the same condition in anatomically proximal sites should not be considered CCs for one another.

Closely related conditions should not be considered CCs for one another.

The creation of the CC Exclusions List was a major project involving hundreds of codes. We have continued to review the remaining CCs to identify additional exclusions and to remove diagnoses from the master list that have been shown not to meet the definition of a CC.\1\

\1\ See the FY 1989 final rule (53 FR 38485) [September 30, 1988] for the revision made for the discharges occurring in FY 1989; the FY 1990 final rule (54 FR 36552) [September 1, 1989] for the FY 1990 revision; the FY 1991 final rule (55 FR 36126) [September 4, 1990] for the FY 1991 revision; the FY 1992 final rule (56 FR 43209)

[August 30, 1991] for the FY 1992 revision; the FY 1993 final rule (57 FR 39753) [September 1, 1992] for the FY 1993 revision; the FY 1994 final rule (58 FR 46278) [September 1, 1993] for the FY 1994 revisions; the FY 1995 final rule (59 FR 45334) [September 1, 1994] for the FY 1995 revisions; the FY 1996 final rule (60 FR 45782)

[September 1, 1995] for the FY 1996 revisions; the FY 1997 final rule (61 FR 46171) [August 30, 1996] for the FY 1997 revisions; the FY 1998 final rule (62 FR 45966) [August 29, 1997] for the FY 1998 revisions; the FY 1999 final rule (63 FR 40954) [July 31, 1998] for the FY 1999 revisions; the FY 2001 final rule (65 FR 47064) [August 1, 2000] for the FY 2001 revisions; the FY 2002 final rule (66 FR 39851) [August 1, 2001] for the FY 2002 revisions; the FY 2003 final rule (67 FR 49998) [August 1, 2002] for the FY 2003 revisions; the FY 2004 final rule (68 FR 45364) [August 1, 2003] for the FY 2004 revisions; and the FY 2005 final rule (69 FR 49848) [August 11, 2004] for the FY 2005 revisions. In the FY 2000 final rule (64 FR 41490) [July 30, 1999], we did not modify the CC Exclusions List because we did not make any changes to the ICD-9-CM codes for FY 2000.

We are proposing a limited revision of the CC Exclusions List to take into account the proposed changes that will be made in the ICD-9- CM diagnosis coding system effective October 1, 2004. (See section II.B.13. of this preamble for a discussion of ICD-9-CM changes.) We are proposing these changes in accordance with the principles established when we created the CC Exclusions List in 1987.

Tables 6G and 6H in the Addendum to this proposed rule contain the revisions to the CC Exclusions List that would be effective for discharges occurring on or after October 1, 2005. Each table shows the principal diagnoses with changes to the excluded CCs. Each of these principal diagnoses is shown with an asterisk, and the additions or deletions to the CC Exclusions List are provided in an indented column immediately following the affected principal diagnosis.

CCs that are added to the list are in Table 6G--Additions to the CC Exclusions List. Beginning with discharges on or after October 1, 2005, the indented diagnoses would not be recognized by the GROUPER as valid CCs for the asterisked principal diagnosis.

CCs that are deleted from the list are in Table 6H--Deletions from the CC Exclusions List. Beginning with discharges on or after October 1, 2005, the indented diagnoses would be recognized by the GROUPER as valid CCs for the asterisked principal diagnosis.

Copies of the original CC Exclusions List applicable to FY 1988 can be obtained from the National Technical Information Service (NTIS) of the Department of Commerce. It is available in hard copy for $152.50 plus shipping and handling. A request for the FY 1988 CC Exclusions List (which should include the identification accession number (PB) 88- 133970) should be made to the following address: National Technical Information Service, United States Department of Commerce, 5285 Port Royal Road, Springfield, VA 22161; or by calling (800) 553-6847.

Users should be aware of the fact that all revisions to the CC Exclusions List (FYs 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2001, 2002, 2003, 2004, and 2005) and those in Tables 6G and 6H of this proposed rule for FY 2006 must be incorporated into the list purchased from NTIS in order to obtain the CC Exclusions List applicable for discharges occurring on or after October 1, 2005. (Note: There was no CC Exclusions List in FY 2000 because we did not make changes to the ICD-9-CM codes for FY 2000.)

Alternatively, the complete documentation of the GROUPER logic, including the current CC Exclusions List, is available from 3M/Health Information Systems (HIS), which, under contract with CMS, is responsible for updating and maintaining the GROUPER program. The current DRG Definitions Manual, Version 22.0, is available for $225.00, which includes $15.00 for shipping and handling. Version 23.0 of this manual, which will include the final FY 2006 DRG changes, will be available for $225.00. These manuals may be obtained by writing 3M/HIS at the following address: 100 Barnes Road, Wallingford, CT 06492; or by calling (203) 949-0303. Please specify the revision or revisions requested.

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12. Review of Procedure Codes in DRGs 468, 476, and 477

(If you choose to comment on issues in this section, please include the caption ``DRGs 468, 476, and 477'' at the beginning of your comment.)

Each year, we review cases assigned to DRG 468 (Extensive O.R. Procedure Unrelated to Principal Diagnosis), DRG 476 (Prostatic O.R. Procedure Unrelated to Principal Diagnosis), and DRG 477 (Nonextensive O.R. Procedure Unrelated to Principal Diagnosis) to determine whether it would be appropriate to change the procedures assigned among these DRGs.

DRGs 468, 476, and 477 are reserved for those cases in which none of the O.R. procedures performed are related to the principal diagnosis. These DRGs are intended to capture atypical cases, that is, those cases not occurring with sufficient frequency to represent a distinct, recognizable clinical group. DRG 476 is assigned to those discharges in which one or more of the following prostatic procedures are performed and are unrelated to the principal diagnosis:

60.0, Incision of prostate.

60.12, Open biopsy of prostate.

60.15, Biopsy of periprostatic tissue.

60.18, Other diagnostic procedures on prostate and periprostatic tissue.

60.21, Transurethral prostatectomy.

60.29, Other transurethral prostatectomy.

60.61, Local excision of lesion of prostate.

60.69, Prostatectomy, not elsewhere classified.

60.81, Incision of periprostatic tissue.

60.82, Excision of periprostatic tissue.

60.93, Repair of prostate.

60.94, Control of (postoperative) hemorrhage of prostate.

60.95, Transurethral balloon dilation of the prostatic urethra.

60.96, Transurethral destruction of prostate tissue by microwave thermotherapy.

60.97, Other transurethral destruction of prostate tissue by other thermotherapy.

60.99, Other operations on prostate.

All remaining O.R. procedures are assigned to DRGs 468 and 477, with DRG 477 assigned to those discharges in which the only procedures performed are nonextensive procedures that are unrelated to the principal diagnosis.\2\

\2\ The original list of the ICD-9-CM procedure codes for the procedures we consider nonextensive procedures, if performed with an unrelated principal diagnosis, was published in Table 6C in section IV. of the Addendum to the FY 1989 final rule (53 FR 38591). As part of the FY 1991 final rule (55 FR 36135), the FY 1992 final rule (56 FR 43212), the FY 1993 final rule (57 FR 23625), the FY 1994 final rule (58 FR 46279), the FY 1995 final rule (59 FR 45336), the FY 1996 final rule (60 FR 45783), the FY 1997 final rule (61 FR 46173), and the FY 1998 final rule (62 FR 45981), we moved several other procedures from DRG 468 to DRG 477, and some procedures from DRG 477 to DRG 468. No procedures were moved in FY 1999, as noted in the final rule (63 FR 40962); in FY 2000 (64 FR 41496); in FY 2001 (65 FR 47064); or in FY 2002 (66 FR 39852). In the FY 2003 final rule (67 FR 49999) we did not move any procedures from DRG 477. However, we did move procedure codes from DRG 468 and placed them in more clinically coherent DRGs. In the FY 2004 final rule (68 FR 45365), we moved several procedures from DRG 468 to DRGs 476 and 477 because the procedures are nonextensive. In the FY 2005 final rule (69 FR 48950), we moved one procedure from DRG 468 to 477. In addition, we added several existing procedures to DRGs 476 and 477.

a. Moving Procedure Codes From DRG 468 or DRG 477 to MDCs

We annually conduct a review of procedures producing assignment to DRG 468 or DRG 477 on the basis of volume, by procedure, to see if it would be appropriate to move procedure codes out of these DRGs into one of the surgical DRGs for the MDC into which the principal diagnosis falls. The data are arrayed two ways for comparison purposes. We look at a frequency count of each major operative procedure code. We also compare procedures across MDCs by volume of procedure codes within each MDC.

We identify those procedures occurring in conjunction with certain principal diagnoses with sufficient frequency to justify adding them to one of the surgical DRGs for the MDC in which the diagnosis falls. Based on this year's review, we did not identify any procedures in DRGs 468 or 477 that should be removed to one of the surgical DRGs. Therefore, in this proposed rule, we are not proposing any changes for FY 2006. b. Reassignment of Procedures Among DRGs 468, 476, and 477

We also annually review the list of ICD-9-CM procedures that, when in combination with their principal diagnosis code, result in assignment to DRGs 468, 476, and 477, to ascertain if any of those procedures should be reassigned from one of these three DRGs to another of the three DRGs based on average charges and the length of stay. We look at the data for trends such as shifts in treatment practice or reporting practice that would make the resulting DRG assignment illogical. If we find these shifts, we would propose to move cases to keep the DRGs clinically similar or to provide payment for the cases in a similar manner. Generally, we move only those procedures for which we have an adequate number of discharges to analyze the data.

It has come to our attention that procedure code 26.12 (Open biopsy of salivary gland or duct) is assigned to DRG 468 (Extensive O.R. Procedure Unrelated to Principal Diagnosis). We believe this to be an error, as code 26.31 (Partial sialoadenectomy), which is a more extensive procedure than code 26.12, is assigned to DRG 477. Therefore, we are proposing to correct this error by moving code 26.12 out of DRG 468 and reassigning it to DRG 477.

We are not proposing to move any procedure codes from DRG 476 to DRGs 468 or 477, or from DRG 477 to DRGs 468 or 476. c. Adding Diagnosis or Procedure Codes to MDCs

Based on our review this year, we are not proposing to add any diagnosis codes to MDCs. 13. Changes to the ICD-9-CM Coding System

As described in section II.B.1. of this preamble, the ICD-9-CM is a coding system used for the reporting of diagnoses and procedures performed on a patient. In September 1985, the ICD-9-CM Coordination and Maintenance Committee was formed. This is a Federal interdepartmental committee, co-chaired by the National Center for Health Statistics (NCHS) and CMS, charged with maintaining and updating the ICD-9-CM system. The Committee is jointly responsible for approving coding changes, and developing errata, addenda, and other modifications to the ICD-9-CM to reflect newly developed procedures and technologies and newly identified diseases. The Committee is also responsible for promoting the use of Federal and non-Federal educational programs and other communication techniques with a view toward standardizing coding applications and upgrading the quality of the classification system.

The Official Version of the ICD-9-CM contains the list of valid diagnosis and procedure codes. (The Official Version of the ICD-9-CM is available from the Government Printing Office on CD-ROM for $25.00 by calling (202) 512-1800.) The Official Version of the ICD-9-CM is no longer available in printed manual form from the Federal Government; it is only available on CD-ROM. Users who need a paper version are referred to one of the many products available from publishing houses.

The NCHS has lead responsibility for the ICD-9-CM diagnosis codes included in the Tabular List and Alphabetic Index for Diseases, while CMS has lead

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responsibility for the ICD-9-CM procedure codes included in the Tabular List and Alphabetic Index for Procedures.

The Committee encourages participation in the above process by health-related organizations. In this regard, the Committee holds public meetings for discussion of educational issues and proposed coding changes. These meetings provide an opportunity for representatives of recognized organizations in the coding field, such as the American Health Information Management Association (AHIMA), the American Hospital Association (AHA), and various physician specialty groups, as well as individual physicians, medical record administrators, health information management professionals, and other members of the public, to contribute ideas on coding matters. After considering the opinions expressed at the public meetings and in writing, the Committee formulates recommendations, which then must be approved by the agencies.

The Committee presented proposals for coding changes for implementation in FY 2006 at a public meeting held on October 7-8, 2004, and finalized the coding changes after consideration of comments received at the meetings and in writing by January 12, 2005. Those coding changes are announced in Tables 6A through 6F of the Addendum to this proposed rule. The Committee held its 2005 meeting on March 31- April l, 2005. Proposed new codes for which there was a consensus of public support and for which complete tabular and indexing charges can be made by May 2005 will be included in the October 1, 2005 update to ICD-9-CM. These additional codes will be included in Tables 6A through 6F of the final rule.

Copies of the minutes of the procedure codes discussions at the Committee's October 7-8, 2004 meeting can be obtained from the CMS Web site: http://www.cms.hhs.gov/paymentsystems/icd9/. The minutes of the

diagnoses codes discussions at the October 7-8, 2004 meeting are found at: http://www.cdc.gov/nchs/icd9.htm. Paper copies of these minutes are

no longer available and the mailing list has been discontinued. These Web sites also provide detailed information about the Committee, including information on requesting a new code, attending a Committee meeting, and timeline requirements and meeting dates.

We encourage commenters to address suggestions on coding issues involving diagnosis codes to: Donna Pickett, Co-Chairperson, ICD-9-CM Coordination and Maintenance Committee, NCHS, Room 2402, 3311 Toledo Road, Hyattsville, MD 20782. Comments may be sent by e-mail to: dfp4@cdc.gov.

Questions and comments concerning the procedure codes should be addressed to: Patricia E. Brooks, Co-Chairperson, ICD-9-CM Coordination and Maintenance Committee, CMS, Center for Medicare Management, Hospital and Ambulatory Policy Group, Division of Acute Care, C4-08-06, 7500 Security Boulevard, Baltimore, MD 21244-1850. Comments may be sent by e-mail to: Patricia.Brooks1@cms.hhs.gov.

The ICD-9-CM code changes that have been approved will become effective October 1, 2005. The new ICD-9-CM codes are listed, along with their DRG classifications, in Tables 6A and 6B (New Diagnosis Codes and New Procedure Codes, respectively) in the Addendum to this proposed rule. As we stated above, the code numbers and their titles were presented for public comment at the ICD-9-CM Coordination and Maintenance Committee meetings. Both oral and written comments were considered before the codes were approved. In this proposed rule, we are only soliciting comments on the proposed classification of these new codes.

For codes that have been replaced by new or expanded codes, the corresponding new or expanded diagnosis codes are included in Table 6A. New procedure codes are shown in Table 6B. Diagnosis codes that have been replaced by expanded codes or other codes or have been deleted are in Table 6C (Invalid Diagnosis Codes). These invalid diagnosis codes will not be recognized by the GROUPER beginning with discharges occurring on or after October 1, 2005. Table 6D contains invalid procedure codes. These invalid procedure codes will not be recognized by the GROUPER beginning with discharges occurring on or after October 1, 2005. Revisions to diagnosis code titles are in Table 6E (Revised Diagnosis Code Titles), which also includes the DRG assignments for these revised codes. Table 6F includes revised procedure code titles for FY 2006.

In the September 7, 2001 final rule implementing the IPPS new technology add-on payments (66 FR 46906), we indicated we would attempt to include proposals for procedure codes that would describe new technology discussed and approved at the April meeting as part of the code revisions effective the following October. As stated previously, ICD-9-CM codes discussed at the March 31-April 1, 2005 Committee meeting that receive consensus and that can be finalized by May 2005 will be included in Tables 6A through 6F of the final rule.

Section 503(a) of Pub. L. 108-173 included a requirement for updating ICD-9-CM codes twice a year instead of a single update on October 1 of each year. This requirement was included as part of the amendments to the Act relating to recognition of new technology under the IPPS. Section 503(a) amended section 1886(d)(5)(K) of the Act by adding a clause (vii) which states that the ``Secretary shall provide for the addition of new diagnosis and procedure codes in April 1 of each year, but the addition of such codes shall not require the Secretary to adjust the payment (or diagnosis-related group classification) * * * until the fiscal year that begins after such date.'' This requirement improves the recognition of new technologies under the IPPS system by providing information on these new technologies at an earlier date. Data will be available 6 months earlier than would be possible with updates occurring only once a year on October 1.

While section 503(a) states that the addition of new diagnosis and procedure codes on April 1 of each year shall not require the Secretary to adjust the payment, or DRG classification under section 1886(d) of the Act until the fiscal year that begins after such date, we have to update the DRG software and other systems in order to recognize and accept the new codes. We also publicize the code changes and the need for a mid-year systems update by providers to capture the new codes. Hospitals also have to obtain the new code books and encoder updates, and make other system changes in order to capture and report the new codes.

The ICD-9-CM Coordination and Maintenance Committee holds its meetings in the Spring and Fall, usually in April and September, in order to update the codes and the applicable payment and reporting systems by October 1 of each year. Items are placed on the agenda for the ICD-9-CM Coordination and Maintenance Committee meeting if the request is received at least 2 months prior to the meeting. This requirement allows time for staff to review and research the coding issues and prepare material for discussion at the meeting. It also allows time for the topic to be publicized in meeting announcements in the Federal Register as well as on the CMS Web site. The public decides whether or not to attend the meeting based on the topics listed on the agenda. Final decisions on code title revisions are currently made by March 1 so that these titles can be included in the IPPS proposed rule. A

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complete addendum describing details of all changes to ICD-9-CM, both tabular and index, are publicized on CMS and NCHS Web pages in May of each year. Publishers of coding books and software use this information to modify their products that are used by health care providers. This 5-month time period has proved to be necessary for hospitals and other providers to update their systems.

A discussion of this timeline and the need for changes are included in the December 4-5, 2003 ICD-9-CM Coordination and Maintenance Committee minutes. The public agreed that there was a need to hold the fall meetings earlier, in September or October, in order to meet the new implementation dates. The public provided comment that additional time would be needed to update hospital systems and obtain new code books and coding software. There was considerable concern expressed about the impact this new April update would have on providers.

In the FY 2005 IPPS final rule, we implemented section 503(a) by developing a mechanism for approving, in time for the April update, diagnoses and procedure code revisions needed to describe new technologies and medical services for purposes of the new technology add-on payment process. We also established the following process for making these determinations. Topics considered during the Fall ICD-9-CM Coordination and Maintenance Committee meeting are considered for an April 1 update if a strong and convincing case is made by the requester at the Committee's public meeting. The request must identify the reason why a new code is needed in April for purposes of the new technology process. The participants at the meeting and those reviewing the Committee meeting summary report are provided the opportunity to comment on this expedited request. All other topics are considered for the October 1 update. Participants at the Committee meeting are encouraged to comment on all such requests. There were no requests for an expedited April l, 2005 implementation of an ICD-9-CM code at the October 7-8, 2004 Committee meeting. Therefore, there were no new ICD- 9-CM codes implemented on April 1, 2005.

We believe that this process captures the intent of section 503(a). This requirement was included in the provision revising the standards and process for recognizing new technology under the IPPS. In addition, the need for approval of new codes outside the existing cycle (October 1) arises most frequently and most acutely where the new codes will capture new technologies that are (or will be) under consideration for new technology add-on payments. Thus, we believe this provision was intended to expedite data collection through the assignment of new ICD- 9-CM codes for new technologies seeking higher payments.

Current addendum and code title information is published on the CMS Web page at: http://www.cms.hhs.gov/paymentsystems/icd9. Summary tables

showing new, revised, and deleted code titles are also posted on the following CMS Web page: http://www.cms.hhs.gov/medlearn/icd9code.asp.

Information on ICD-9-CM diagnosis codes, along with the Official ICD-9- CM Coding Guidelines, can be found on the Wep page at: http://www.cdc.gov/nchs/icd9.htm. Information on new, revised, and deleted

ICD-9-CM codes is also provided to the AHA for publication in the Coding Clinic for ICD-9-CM. AHA also distributes information to publishers and software vendors.

CMS also sends copies of all ICD-9-CM coding changes to its contractors for use in updating their systems and providing education to providers.

These same means of disseminating information on new, revised, and deleted ICD-9-CM codes will be used to notify providers, publishers, software vendors, contractors, and others of any changes to the ICD-9- CM codes that are implemented in April. Currently, code titles are also published in the IPPS proposed and final rules. The code titles are adopted as part of the ICD-9-CM Coordination and Maintenance Committee process. The code titles are not subject to comment in the proposed or final rules. We will continue to publish the October code updates in this manner within the IPPS proposed and final rules. For codes that are implemented in April, we will assign the new procedure code to the same DRG in which its predecessor code was assigned so there will be no DRG impact as far as DRG assignment. This mapping was specified by Pub. L. 108-173. Any midyear coding updates will be available through the websites indicated above and through the Coding Clinic for ICD-9-CM. Publishers and software vendors currently obtain code changes through these sources in order to update their code books and software systems. We will strive to have the April 1 updates available through these websites 5 months prior to implementation (that is, early November of the previous year), as is the case for the October 1 updates. Codebook publishers are evaluating how they will provide any code updates to their subscribers. Some publishers may decide to publish mid-year book updates. Others may decide to sell an addendum that lists the changes to the October 1 code book. Coding personnel should contact publishers to determine how they will update their books. CMS and its contractors will also consider developing provider education articles concerning this change to the effective date of certain ICD-9-CM codes. 14. Other Issues: Acute Intermittent Porphyria

Acute intermittent porphyria is a rare metabolic disorder. The condition is described by code 277.1 (Disorders of porphyrin metabolism). Code 277.1 is assigned to DRG 299 (Inborn Errors of Metabolism) under MDC 10 (Endocrine, Nutritional, and Metabolic Diseases and Disorders).

In the FY 2005 final rule (69 FR 48981), we discussed the DRG assignment of acute intermittent porphyria. This discussion was a result of correspondence that we received during the comment period for the FY 2005 proposed rule in which the commenter suggested that Medicare hospitalization payments do not accurately reflect the cost of treatment. At that time, we indicated that we would take this comment into consideration when we analyzed the MedPAR data for this proposed rule for FY 2006.

Our review of the most recent MedPAR data shows a total of 1,370 cases overall in DRG 299, of which 471 had a principal diagnosis coded as 277.1. The average length of stay for all cases in DRG 299 was 5.17 days, while the average length of stay for porphyria cases with code 277.1 was 6.0 days. The average charges for all cases in DRG 299 were $15,891, while the average changes for porphyria cases with code 277.1 were $21,920. Based on our analysis of these data, we do not believe that there is a sufficient difference between the average charges and average length of stay for these cases to justify a change to the DRG assignment for treating this condition.

C. Proposed Recalibration of DRG Weights

(If you choose to comment on issues in this section, please include the caption ``DRG Weights'' at the beginning of your comment.)

We are proposing to use the same basic methodology for the FY 2006 recalibration as we did for FY 2005 (FY 2005 IPPS final rule (69 FR 48981)). That is, we have recalibrated the DRG weights based on charge data for

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Medicare discharges using the most current charge information available (the FY 2004 MedPAR file).

The MedPAR file is based on fully coded diagnostic and procedure data for all Medicare inpatient hospital bills. The FY 2004 MedPAR data used in this final rule include discharges occurring between October 1, 2003 and September 30, 2004, based on bills received by CMS through December 31, 2004, from all hospitals subject to the IPPS and short- term acute care hospitals in Maryland (which are under a waiver from the IPPS under section 1814(b)(3) of the Act). The FY 2004 MedPAR file includes data for approximately 11,910,025 Medicare discharges. Discharges for Medicare beneficiaries enrolled in a Medicare+Choice managed care plan are excluded from this analysis. The data excludes CAHs, including hospitals that subsequently became CAHs after the period from which the data were taken.

The proposed methodology used to calculate the DRG relative weights from the FY 2004 MedPAR file is as follows:

To the extent possible, all the claims were regrouped using the DRG classification revisions discussed in section II.B. of this preamble.

The transplant cases that were used to establish the relative weight for heart and heart-lung, liver, and lung transplants (DRGs 103, 480, and 495) were limited to those Medicare-approved transplant centers that have cases in the FY 2004 MedPAR file. (Medicare coverage for heart, heart-lung, liver, and lung transplants is limited to those facilities that have received approval from CMS as transplant centers.)

Organ acquisition costs for kidney, heart, heart-lung, liver, lung, pancreas, and intestinal (or multivisceral organs) transplants continue to be paid on a reasonable cost basis. Because these acquisition costs are paid separately from the prospective payment rate, it is necessary to subtract the acquisition charges from the total charges on each transplant bill that showed acquisition charges before computing the average charge for the DRG and before eliminating statistical outliers.

Charges were standardized to remove the effects of differences in area wage levels, indirect medical education and disproportionate share payments, and, for hospitals in Alaska and Hawaii, the applicable cost-of-living adjustment.

The average standardized charge per DRG was calculated by summing the standardized charges for all cases in the DRG and dividing that amount by the number of cases classified in the DRG. A transfer case is counted as a fraction of a case based on the ratio of its transfer payment under the per diem payment methodology to the full DRG payment for nontransfer cases. That is, a transfer case receiving payment under the transfer methodology equal to half of what the case would receive as a nontransfer would be counted as 0.5 of a total case.

Statistical outliers were eliminated by removing all cases that are beyond 3.0 standard deviations from the mean of the log distribution of both the charges per case and the charges per day for each DRG.

The average charge for each DRG was then recomputed (excluding the statistical outliers) and divided by the national average standardized charge per case to determine the relative weight.

The proposed new weights are normalized by an adjustment factor of 1.47263 so that the average case weight after recalibration is equal to the average case weight before recalibration. This proposed adjustment is intended to ensure that recalibration by itself neither increases nor decreases total payments under the IPPS.

When we recalibrated the DRG weights for previous years, we set a threshold of 10 cases as the minimum number of cases required to compute a reasonable weight. We used that same case threshold in recalibrating the proposed DRG weights for FY 2006. Using the FY 2004 MedPAR data set, there are 41 DRGs that contain fewer than 10 cases. We are proposing to compute the weights for these low-volume DRGs by adjusting the FY 2005 weights of these DRGs by the percentage change in the average weight of the cases in the other DRGs.

Section 1886(d)(4)(C)(iii) of the Act requires that, beginning with FY 1991, reclassification and recalibration changes be made in a manner that assures that the aggregate payments are neither greater than nor less than the aggregate payments that would have been made without the changes. Although normalization is intended to achieve this effect, equating the average case weight after recalibration to the average case weight before recalibration does not necessarily achieve budget neutrality with respect to aggregate payments to hospitals because payments to hospitals are affected by factors other than average case weight. Therefore, as we have done in past years and as discussed in section II.A.4.a. of the Addendum to this proposed rule, we are making a budget neutrality adjustment to ensure that the requirement of section 1886(d)(4)(C)(iii) of the Act is met.

D. Proposed LTC-DRG Reclassifications and Relative Weights for LTCHs for FY 2006

(If you choose to comment on issues in this section, please include the caption ``LTC-DRGs'' at the beginning of your comment.) 1. Background

In the June 6, 2003 LTCH PPS final rule (68 FR 34122), we changed the LTCH PPS annual payment rate update cycle to be effective July 1 through June 30 instead of October 1 through September 30. In addition, because the patient classification system utilized under the LTCH PPS is based directly on the DRGs used under the IPPS for acute care hospitals, in that same final rule, we explained that the annual update of the long-term care diagnosis-related group (LTC-DRG) classifications and relative weights will continue to remain linked to the annual reclassification and recalibration of the CMS-DRGs used under the IPPS. In that same final rule, we specified that we will continue to update the LTC-DRG classifications and relative weights to be effective for discharges occurring on or after October 1 through September 30 each year. Furthermore, we stated that we will publish the annual update of the LTC-DRGs in the proposed and final rules for the IPPS.

In the past, the annual update to the IPPS DRGs has been based on the annual revisions to the ICD-9-CM codes and was effective each October 1. As discussed in the FY 2005 IPPS final rule (69 FR 48954 through 48957) and in the February 3, 2005 LTCH PPS proposed rule (70 FR 5729 through 5733), with the implementation of section 503 (a) of Pub. L. 108-173, there is the possibility that one feature of the GROUPER software program may be updated twice during a Federal fiscal year (October 1 and April 1) as required by the statute for the IPPS. Specifically, ICD-9-CM diagnosis and procedure codes for new medical technology may be created and added to existing DRGs in the middle of the Federal fiscal year on April 1. This policy change will have no effect, however, on the LTC-DRG relative weights which will continue to be updated only once a year (October 1), nor will there be any impact on Medicare payments under the LTCH PPS. The use of the ICD-9-CM code set is also compliant with the current requirements of the Transactions and Code Sets Standards regulations at 45 CFR Parts 160 and 162, promulgated in accordance with the Health Insurance Portability and Accountability Act of 1996 (HIPAA), Pub. L. 104-191.

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In the health care industry, historically annual changes to the ICD-9-CM codes were effective for discharges occurring on or after October 1 each year. Thus, the manual and electronic versions of the GROUPER software, which are based on the ICD-9-CM codes, were also revised annually and effective for discharges occurring on or after October 1 each year. As noted above, the patient classification system used under the LTCH PPS (LTC-DRGs) is based on the patient classification system used under the IPPS (CMS-DRGs), which historically had been updated annually and effective for discharges occurring on or after October 1 through September 30 each year. As mentioned above, the ICD-9-CM coding update process has been revised, as discussed in greater detail in the FY 2005 IPPS final rule (69 FR 48954 through 48957). Specifically, section 503(a) of Pub. L. 108-173 includes a requirement for updating ICD-9-CM codes as often as twice a year instead of the current process of annual updates on October 1 of each year. This requirement is included as part of the amendments to the Act relating to recognition of new medical technology under the IPPS. Section 503(a) of Pub L. 108-173 amended section 1886(d)(5)(K) of the Act by adding a new clause (vii) which states that ``the Secretary shall provide for the addition of new diagnosis and procedure codes in

[sic] April 1 of each year, but the addition of such codes shall not require the Secretary to adjust the payment (or diagnosis-related group classification) * * * until the fiscal year that begins after such date.'' This requirement will improve the recognition of new technologies under the IPPS by accounting for those ICD-9-CM codes in the MedPAR claims data at an earlier date. Despite the fact that aspects of the GROUPER software may be updated to recognize any new technology ICD-9-CM codes, as discussed in the February 3, 2005 LTCH PPS proposed rule (70 FR 5730 through 5733), there will be no impact on either LTC-DRG assignments or payments under the LTCH PPS at that time. That is, changes to the LTC-DRGs (such as the creation or deletion of LTC-DRGs) and the relative weights will continue to be updated in the manner and timing (October 1) as they are now.

As noted above and as described in the February 3, 2005 LTCH PPS proposed rule (70 FR 5730), updates to the GROUPER for both the IPPS and the LTCH PPS (with respect to relative weights and the creation or deletion of DRGs) are made in the annual IPPS proposed and final rules and are effective each October 1. We explained in the FY 2005 IPPS final rule (69 FR 48955 and 48956), that since we do not publish a midyear IPPS rule, April 1 code updates discussed above will not be published in a midyear IPPS rule. Rather, we will assign any new diagnostic or procedure codes to the same DRG in which its predecessor code was assigned, so that there will be no impact on the DRG assignments. Any proposed coding updates will be available through the websites indicated in the same rule and provided above in section II.B. of this preamble and through the Coding Clinic for ICD-9-CM. Publishers and software vendors currently obtain code changes through these sources in order to update their code books and software system. If new codes are implemented on April 1, revised code books and software systems, including the GROUPER software program, will be necessary because we must use current ICD-9-CM codes. Therefore, for purposes of the LTCH PPS, since each ICD-9-CM code must be included in the GROUPER algorithm to classify each case into a LTC-DRG, the GROUPER software program used under the LTCH PPS would need to be revised to accommodate any new codes.

As we discussed in the FY 2005 IPPS final rule (69 FR 48956), in implementing section 503(a) of Pub. L. 108-173, there will only be an April 1 update if new technology codes are requested and approved. It should be noted that any new codes created for April 1 implementation will be limited to those diagnosis and procedure code revisions primarily needed to describe new technologies and medical services. However, we reiterate that the process of discussing updates to the ICD-9-CM has been an open process through the ICD-9-CM C&M Committee since 1995. Requestors will be given the opportunity to present the merits of their proposed new code and make a clear and convincing case for the need to update ICD-9-CM codes for purposes of the IPPS new technology add-on payment process through an April 1 update.

In addition, in the FY 2005 IPPS final rule (69 FR 48956), we stated that at the October 2004 ICD-9-CM Coordination and Maintenance Committee meeting, no new codes were proposed for an April 1, 2005 implementation, and the next update to the ICD-9-CM coding system would not occur until October 1, 2005 (FY 2006). Presently, as there were no coding changes suggested for an April 1, 2005 update, the ICD-9-CM coding set implemented on October 1, 2004 will continue through September 30, 2005 (FY 2005). The proposed update to the ICD-9-CM coding system for FY 2006 is discussed above in section II.B. of this preamble.

In this proposed rule, we are proposing revisions to the LTC-DRG classifications and relative weights and, to the extent that they are finalized, we will publish them in the corresponding IPPS final rule, to be effective October 1, 2005 through September 30, 2006 (FY 2006), using the latest available data. The proposed LTC-DRGs and relative weights for FY 2006 in this proposed rule are based on the proposed IPPS DRGs (GROUPER Version 23.0) discussed in section II. of this proposed rule. 2. Proposed Changes in the LTC-DRG Classifications a. Background

Section 123 of Pub. L. 106-113 specifically requires that the PPS for LTCHs be a per discharge system with a DRG-based patient classification system reflecting the differences in patient resources and costs in LTCHs while maintaining budget neutrality. Section 307(b)(1) of Pub. L. 106-554 modified the requirements of section 123 of Pub. L. 106-113 by specifically requiring that the Secretary examine ``the feasibility and the impact of basing payment under such a system

[the LTCH PPS] on the use of existing (or refined) hospital diagnosis- related groups (DRGs) that have been modified to account for different resource use of long-term care hospital patients as well as the use of the most recently available hospital discharge data.''

In accordance with section 307(b)(1) of Pub. L. 106-554 and Sec. 412.515 of our existing regulations, the LTCH PPS uses information from LTCH patient records to classify patient cases into distinct LTC-DRGs based on clinical characteristics and expected resource needs. The LTC- DRGs used as the patient classification component of the LTCH PPS correspond to the DRGs under the IPPS for acute care hospitals. Thus, in this proposed rule, we are proposing to use the IPPS GROUPER Version 23.0 for FY 2006 to process LTCH PPS claims for LTCH occurring from October 1, 2005 through September 30, 2006. The proposed changes to the CMS DRG classification system used under the IPPS for FY 2006 (GROUPER Version 23.0) are discussed in section II.B. of the preamble to this proposed rule.

Under the LTCH PPS, we determine relative weights for each of the CMS DRGs to account for the difference in resource use by patients exhibiting the

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case complexity and multiple medical problems characteristic of LTCH patients. In a departure from the IPPS, as we discussed in the August 30, 2002 LTCH PPS final rule (67 FR 55985), which implemented the LTCH PPS, and the FY 2004 IPPS final rule (68 FR 45374), we use low-volume quintiles in determining the LTC-DRG weights for LTC-DRGs with less than 25 LTCH cases, because LTCHs do not typically treat the full range of diagnoses as do acute care hospitals. Specifically, we group those low-volume LTC-DRGs (LTC-DRGs with fewer than 25 cases) into 5 quintiles based on average charge per discharge. (A listing of the composition of low-volume quintiles for the FY 2005 LTC-DRGs (based on FY 2003 MedPAR data) appears in section II.D.3. of the FY 2005 IPPS final rule (69 FR 48985 through 48989).) We also adjust for cases in which the stay at the LTCH is less than or equal to five-sixths of the geometric average length of stay; that is, short-stay outlier cases (Sec. 412.529), as discussed below in section II.D.4. of this preamble. b. Patient Classifications into DRGs

Generally, under the LTCH PPS, Medicare payment is made at a predetermined specific rate for each discharge; that is, payment varies by the LTC-DRG to which a beneficiary's stay is assigned. Similar to case classification for acute care hospitals under the IPPS (see section II.B. of this preamble), cases are classified into LTC-DRGs for payment under the LTCH PPS based on the principal diagnosis, up to eight additional diagnoses, and up to six procedures performed during the stay, as well as age, sex, and discharge status of the patient. The diagnosis and procedure information is reported by the hospital using codes from the ICD-9-CM.

As discussed in section II.B. of this preamble, the CMS DRGs are organized into 25 major diagnostic categories (MDCs), most of which are based on a particular organ system of the body; the remainder involve multiple organ systems (such as MDC 22, Burns). Accordingly, the principal diagnosis determines MDC assignment. Within most MDCs, cases are then divided into surgical DRGs and medical DRGs. Some surgical and medical DRGs are further differentiated based on the presence or absence of CCs. (See section II.B. of this preamble for further discussion of surgical DRGs and medical DRGs.)

Because the assignment of a case to a particular LTC-DRG will help determine the amount that is paid for the case, it is important that the coding is accurate. As used under the IPPS, classifications and terminology used under the LTCH PPS are consistent with the ICD-9-CM and the Uniform Hospital Discharge Data Set (UHDDS), as recommended to the Secretary by the National Committee on Vital and Health Statistics (``Uniform Hospital Discharge Data: Minimum Data Set, National Center for Health Statistics, April 1980'') and as revised in 1984 by the Health Information Policy Council (HIPC) of the U.S. Department of Health and Human Services. We point out again that the ICD-9-CM coding terminology and the definitions of principal and other diagnoses of the UHDDS are consistent with the requirements of the Transactions and Code Sets Standards under HIPAA (45 CFR Parts 160 and 162).

The emphasis on the need for proper coding cannot be overstated. Inappropriate coding of cases can adversely affect the uniformity of cases in each LTC-DRG and produce inappropriate weighting factors at recalibration and result in inappropriate payments under the LTCH PPS. LTCHs are to follow the same coding guidelines used by the acute care hospitals to ensure accuracy and consistency in coding practices. There will be only one LTC-DRG assigned per long-term care hospitalization; it will be assigned at the discharge. Therefore, it is mandatory that the coders continue to report the same principal diagnosis on all claims and include all diagnostic codes that coexist at the time of admission, that are subsequently developed, or that affect the treatment received. Similarly, all procedures performed during that stay are to be reported on each claim.

Upon the discharge of the patient from a LTCH, the LTCH must assign appropriate diagnosis and procedure codes from the ICD-9-CM. Completed claim forms are to be submitted electronically to the LTCH's Medicare fiscal intermediary. Medicare fiscal intermediaries enter the clinical and demographic information into their claims processing systems and subject this information to a series of automated screening processes called the Medicare Code Editor (MCE). These screens are designed to identify cases that require further review before assignment into an LTC-DRG can be made.

After screening through the MCE, each LTCH claim will be classified into the appropriate LTC-DRG by the Medicare LTCH GROUPER. The LTCH GROUPER is specialized computer software based on the same GROUPER used under the IPPS. After the LTC-DRG is assigned, the Medicare fiscal intermediary determines the prospective payment by using the Medicare LTCH PPS PRICER program, which accounts for LTCH hospital-specific adjustments. As provided for under the IPPS, we provide an opportunity for the LTCH to review the LTC-DRG assignments made by the fiscal intermediary and to submit additional information within a specified timeframe (Sec. 412.513(c)).

The GROUPER is used both to classify past cases in order to measure relative hospital resource consumption to establish the LTC-DRG weights and to classify current cases for purposes of determining payment. The records for all Medicare hospital inpatient discharges are maintained in the MedPAR file. The data in this file are used to evaluate possible DRG classification changes and to recalibrate the DRG weights during our annual update (as discussed in section II. of this preamble). The LTC-DRG relative weights are based on data for the population of LTCH discharges, reflecting the fact that LTCH patients represent a different patient mix than patients in short-term acute care hospitals. 3. Development of the Proposed FY 2006 LTC-DRG Relative Weights a. General Overview of Development of the LTC-DRG Relative Weights

As we stated in the August 30, 2002 LTCH PPS final rule (67 FR 55981), one of the primary goals for the implementation of the LTCH PPS is to pay each LTCH an appropriate amount for the efficient delivery of care to Medicare patients. The system must be able to account adequately for each LTCH's case-mix in order to ensure both fair distribution of Medicare payments and access to adequate care for those Medicare patients whose care is more costly. To accomplish these goals, we adjust the LTCH PPS standard Federal prospective payment system rate by the applicable LTC-DRG relative weight in determining payment to LTCHs for each case. Under the LTCH PPS, relative weights for each LTC- DRG are a primary element used to account for the variations in cost per discharge and resource utilization among the payment groups (Sec. 412.515). To ensure that Medicare patients classified to each LTC-DRG have access to an appropriate level of services and to encourage efficiency, we calculate a relative weight for each LTC-DRG that represents the resources needed by an average inpatient LTCH case in that LTC-DRG. For example, cases in an LTC-DRG with a relative weight of 2 will, on average, cost twice as much as cases in an LTC-DRG with a weight of 1.

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b. Data

To calculate the proposed LTC-DRG relative weights for FY 2006 in this proposed rule, we obtained total Medicare allowable charges from FY 2004 Medicare hospital bill data from the December 2004 update of the MedPAR file, and we used the proposed Version 23.0 of the CMS GROUPER for IPPS (as discussed in section II.B. of this preamble) to classify cases. Consistent with the methodology under the IPPS, we are proposing to recalculate the FY 2006 LTC-DRG relative weights based on the best available data for this proposed rule.

As we discussed in the FY 2005 IPPS final rule (69 FR 48984), we have excluded the data from LTCHs that are all-inclusive rate providers and LTCHs that are reimbursed in accordance with demonstration projects authorized under section 402(a) of Pub. L. 90-248 (42 U.S.C. 1395b-1) or section 222(a) of Pub. L. 92-603 (42 U.S.C. 1395b-1). Therefore, in the development of the proposed FY 2006 LTC-DRG relative weights, we have excluded the data of the 19 all-inclusive rate providers and the 3 LTCHs that are paid in accordance with demonstration projects that had claims in the FY 2003 MedPAR file.

In the FY 2005 IPPS final rule (6 FR 48984), we discussed coding inaccuracies that were found in the claims data for a large chain of LTCHs in the FY 2002 MedPAR file, which were used to determine the LTC- DRG relative weights for FY 2004. As we discussed in the same final rule, after notifying the large chain of LTCHs whose claims contained the coding inaccuracies to request that they resubmit those claims with the correct diagnosis, from an analysis of LTCH claims data from the December 2003 update of the FY 2003 MedPAR file, it appeared that such claims data no longer contain coding errors. Therefore, it was not necessary to correct the FY 2003 MedPAR data for the development of the FY 2005 LTC-DRGs and relative weights established in the same final rule.

As stated above, in this proposed rule, we are proposing to use the December 2004 update of the FY 2004 MedPAR file for the determination of the proposed FY 2006 LTC-DRG relative weights as these are the best available data. Based on an analysis of LTCH claims data from the December 2004 update of the FY 2004 MedPAR file, it appears that such claims data do not contain coding inaccuracies found previously in LTCH claims data. Therefore, it was not necessary to correct the FY 2004 MedPAR data for the development of the proposed FY 2006 LTC-DRGs and relative weights presented in this proposed rule. c. Hospital-Specific Relative Value Methodology

By nature, LTCHs often specialize in certain areas, such as ventilator-dependent patients and rehabilitation and wound care. Some case types (DRGs) may be treated, to a large extent, in hospitals that have, from a perspective of charges, relatively high (or low) charges. This nonarbitrary distribution of cases with relatively high (or low) charges in specific LTC-DRGs has the potential to inappropriately distort the measure of average charges. To account for the fact that cases may not be randomly distributed across LTCHs, we use a hospital- specific relative value method to calculate the LTC-DRG relative weights instead of the methodology used to determine the DRG relative weights under the IPPS described above in section II.C. of this preamble. We believe this method will remove this hospital-specific source of bias in measuring LTCH average charges. Specifically, we reduce the impact of the variation in charges across providers on any particular LTC-DRG relative weight by converting each LTCH's charge for a case to a relative value based on that LTCH's average charge.

Under the hospital-specific relative value method, we standardize charges for each LTCH by converting its charges for each case to hospital-specific relative charge values and then adjusting those values for the LTCH's case-mix. The adjustment for case-mix is needed to rescale the hospital-specific relative charge values (which, by definition, averages 1.0 for each LTCH). The average relative weight for a LTCH is its case-mix, so it is reasonable to scale each LTCH's average relative charge value by its case-mix. In this way, each LTCH's relative charge value is adjusted by its case-mix to an average that reflects the complexity of the cases it treats relative to the complexity of the cases treated by all other LTCHs (the average case- mix of all LTCHs).

In accordance with the methodology established under Sec. 412.523, we standardize charges for each case by first dividing the adjusted charge for the case (adjusted for short-stay outliers under Sec. 412.529 as described in section II.D.4. (step 3) of this preamble) by the average adjusted charge for all cases at the LTCH in which the case was treated. Short-stay outliers under Sec. 412.529 are cases with a length of stay that is less than or equal to five-sixths the average length of stay of the LTC-DRG. The average adjusted charge reflects the average intensity of the health care services delivered by a particular LTCH and the average cost level of that LTCH. The resulting ratio is multiplied by that LTCH's case-mix index to determine the standardized charge for the case.

Multiplying by the LTCH's case-mix index accounts for the fact that the same relative charges are given greater weight in a LTCH with higher average costs than they would at a LTCH with low average costs which is needed to adjust each LTCH's relative charge value to reflect its case-mix relative to the average case-mix for all LTCHs. Because we standardize charges in this manner, we count charges for a Medicare patient at a LTCH with high average charges as less resource intensive than they would be at a LTCH with low average charges. For example, a $10,000 charge for a case in a LTCH with an average adjusted charge of $17,500 reflects a higher level of relative resource use than a $10,000 charge for a case in a LTCH with the same case-mix, but an average adjusted charge of $35,000. We believe that the adjusted charge of an individual case more accurately reflects actual resource use for an individual LTCH because the variation in charges due to systematic differences in the markup of charges among LTCHs is taken into account. d. Proposed Low-Volume LTC-DRGs

In order to account for LTC-DRGs with low-volume (that is, with fewer than 25 LTCH cases), in accordance with the methodology established in the August 30, 2002 LTCH PPS final rule (67 FR 55984), we group those low-volume LTC-DRGs into one of five categories (quintiles) based on average charges, for the purposes of determining relative weights. For this proposed rule, using LTCH cases from the December 2004 update of the FY 2004 MedPAR file, we identified 172 LTC- DRGs that contained between 1 and 24 cases. This list of proposed LTC- DRGs was then divided into one of the 5 low-volume quintiles, each containing a minimum of 34 LTC-DRGs (172/5 = 34 with 2 LTC-DRGs as the remainder). For FY 2006, we are proposing to make an assignment to a specific low-volume quintile by sorting the low-volume proposed LTC- DRGs in ascending order by average charge. For this proposed rule, this results in an assignment to a specific low volume quintile of the sorted 172 low-volume proposed LTC-DRGs by ascending order by average charge. Because the number of LTC-DRGs with less than 25 LTCH cases is not evenly divisible by five, the average charge of the low-volume proposed LTC-DRG was used to determine which low-

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volume quintile received the additional proposed LTC-DRG. After sorting the 172 low-volume LTC-DRGs in ascending order, we are proposing that the first fifth of low-volume LTC-DRGs with the lowest average charge would be grouped into Quintile 1. The highest average charge cases would be grouped into Quintile 5. Since the average charge of the proposed 35th LTC-DRG in the sorted list is closer to the proposed 34th LTC-DRG's average charge (assigned to Quintile 1) than to the average charge of the proposed 36th LTC-DRG in the sorted list (to be assigned to Quintile 2), we are proposing to place it into Quintile 1. This process was repeated through the remaining low-volume proposed LTC-DRGs so that 2 proposed low-volume quintiles contain 35 proposed LTC-DRGs and 3 proposed low-volume quintiles contain 34 proposed LTC-DRGs.

In order to determine the proposed relative weights for the proposed LTC-DRGs with low volume for FY 2006, in accordance with the methodology established in the August 30, 2002 LTCH PPS final rule (67 FR 55984), we are proposing to use the proposed five low-volume quintiles described above. The composition of each of the proposed five low-volume quintiles shown in the chart below would be used in determining the proposed LTC-DRG relative weights for FY 2006. We would determine a proposed relative weight and (geometric) average length of stay for each of the proposed five low-volume quintiles using the formula that we apply to the regular proposed LTC-DRGs (25 or more cases), as described below in section II.D.4. of this preamble. We are proposing to assign the same relative weight and average length of stay to each of the proposed LTC-DRGs that make up that proposed low-volume quintile. We note that, as this system is dynamic, it is possible that the number and specific type of LTC-DRGs with a low volume of LTCH cases will vary in the future. We use the best available claims data in the MedPAR file to identify low-volume LTC-DRGs and to calculate the relative weights based on our methodology.

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4. Steps for Determining the Proposed FY 2006 LTC-DRG Relative Weights

As we noted previously, the proposed FY 2006 LTC-DRG relative weights are determined in accordance with the methodology established in the August 1, 2003 IPPS final rule (68 FR 45367). In summary, LTCH cases must be grouped in the appropriate LTC-DRG, while taking into account the low-volume proposed LTC-DRGs as described above, before the proposed FY 2006 LTC-DRG relative weights can be determined. After grouping the cases in the appropriate proposed LTC-DRG, we are proposing to calculate the proposed relative weights for FY 2006 in this proposed rule by first removing statistical outliers and cases with a length of stay of 7 days or less, as discussed in greater detail below. Next, we are proposing to adjust the number of cases in each proposed LTC-DRG for the effect of short-stay outlier cases under Sec. 412.529, as also discussed in greater detail below. The short-stay adjusted discharges and corresponding charges are used to calculate ``relative adjusted weights'' in each proposed LTC-DRG using the hospital-specific relative value method described above.

Below we discuss in detail the steps for calculating the proposed FY 2006 LTC-DRG relative weights.

Step 1--Remove statistical outliers.

The first step in the calculation of the proposed FY 2006 LTC-DRG relative weights is to remove statistical outlier cases. We define statistical outliers as cases that are outside of 3.0 standard deviations from the mean of the log distribution of both charges per case and the charges per day for each LTC-DRG. These statistical outliers are removed prior to calculating the proposed relative weights. We believe that they may represent aberrations in the data that distort the measure of average resource use. Including those LTCH cases in the calculation of the proposed relative weights could result in an inaccurate proposed relative weight that does not truly reflect relative resource use among the proposed LTC-DRGs.

Step 2--Remove cases with a length of stay of 7 days or less.

The proposed FY 2006 LTC-DRG relative weights reflect the average of resources used on representative cases of a specific type. Generally, cases with a length of stay 7 days or less do not belong in a LTCH because these stays do not fully receive or benefit from treatment that is typical in a LTCH stay, and full resources are often not used in the earlier stages of admission to a LTCH. If we were to include stays of 7 days or less in the computation of the proposed FY 2006 LTC-DRG relative weights, the value of many proposed relative weights would decrease and, therefore, payments would decrease to a level that may no longer be appropriate.

We do not believe that it would be appropriate to compromise the integrity of the payment determination for those LTCH cases that actually benefit from and receive a full course of treatment at a LTCH, in order to include data from these very short-stays. Thus, in determining the proposed FY 2006 LTC-DRG relative weights, we remove LTCH cases with a length of stay of 7 days or less.

Step 3--Adjust charges for the effects of short-stay outliers.

After removing cases with a length of stay of 7 days or less, we are left with cases that have a length of stay of greater than or equal to 8 days. The next step in the calculation of the proposed FY 2006 LTC-DRG relative weights is to adjust each LTCH's charges per discharge for those remaining cases for the effects of short-stay outliers as defined in Sec. 412.529(a). (However, we note that even if a case was removed in Step 2 (that is, cases with a length of stay of 7 days or less), it was paid as a short-stay outlier if its length of stay was less than or equal to five-sixths of the average length of stay of the LTC-DRG, in accordance with Sec. 412.529.)

We make this adjustment by counting a short-stay outlier as a fraction of a discharge based on the ratio of the length of stay of the case to the average length of stay for the proposed LTC-DRG for nonshort-stay outlier cases. This has the effect of proportionately reducing the impact of the lower charges for the short-stay outlier cases in calculating the average charge for the proposed LTC-DRG. This process produces the same result as if the actual charges per discharge of a short-stay outlier case were adjusted to what they would have been had the patient's length of stay been equal to the average length of stay of the proposed LTC-DRG.

As we explained in the FY 2005 IPPS final rule (69 FR 48991), counting short-

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stay outlier cases as full discharges with no adjustment in determining the proposed LTC-DRG relative weights would lower the proposed LTC-DRG relative weight for affected proposed LTC-DRGs because the relatively lower charges of the short-stay outlier cases would bring down the average charge for all cases within a proposed LTC-DRG. This would result in an ``underpayment'' to nonshort-stay outlier cases and an ``overpayment'' to short-stay outlier cases. Therefore, in this proposed rule, we adjust for short-stay outlier cases under Sec. 412.529 in this manner because it results in more appropriate payments for all LTCH cases.

Step 4--Calculate the Proposed FY 2006 LTC-DRG relative weights on an iterative basis.

The process of calculating the proposed LTC-DRG relative weights using the hospital specific relative value methodology is iterative. First, for each LTCH case, we calculate a hospital-specific relative charge value by dividing the short-stay outlier adjusted charge per discharge (see step 3) of the LTCH case (after removing the statistical outliers (see step 1)) and LTCH cases with a length of stay of 7 days or less (see step 2) by the average charge per discharge for the LTCH in which the case occurred. The resulting ratio is then multiplied by the LTCH's case-mix index to produce an adjusted hospital-specific relative charge value for the case. An initial case-mix index value of 1.0 is used for each LTCH.

For each proposed LTC-DRG, the proposed FY 2006 LTC-DRG relative weight is calculated by dividing the average of the adjusted hospital- specific relative charge values (from above) for the proposed LTC-DRG by the overall average hospital-specific relative charge value across all cases for all LTCHs. Using these recalculated proposed LTC-DRG relative weights, each proposed LTCH's average relative weight for all of its cases (case-mix) is calculated by dividing the sum of all the proposed LTCH's LTC-DRG relative weights by its total number of cases. The LTCHs' hospital-specific relative charge values above are multiplied by these hospital specific case-mix indexes. These hospital- specific case-mix adjusted relative charge values are then used to calculate a new set of proposed LTC-DRG relative weights across all LTCHs. In this proposed rule, this iterative process is continued until there is convergence between the weights produced at adjacent steps, for example, when the maximum difference is less than 0.0001.

Step 5-Adjust the proposed FY 2006 LTC-DRG relative weights to account for nonmonotonically increasing relative weights.

As explained in section II.B. of this preamble, the proposed FY 2006 CMS DRGs, which the proposed FY 2006 LTC-DRGs are based, contain ``pairs'' that are differentiated based on the presence or absence of CCs. The proposed LTC-DRGs with CCs are defined by certain secondary diagnoses not related to or inherently a part of the disease process identified by the principal diagnosis, but the presence of additional diagnoses does not automatically g