Knowledge Base Article

CMS released the 2,087 page display copy of the FY 2023 IPPS Final Rule (CMS-1771-F) on Monday August 1, 2022. This article highlights finalized changes to calculating relative weights and MS-DRG Refinements.

Calculating MS-DRG Relative Weights

CMS notes, in a related Fact Sheet, it is reasonable to assume Medicare beneficiaries will continue to be hospitalized with COVID-19 in FY 2023. They also believe admissions will be fewer than is reflected in the FY 2021 data.

Based on these assumptions, CMS finalized calculating relative weights for FY 2023 by:

• Calculating two sets of relative weights, one including and one excluding COVID-19 claims, and
• Averaging the two sets of relative weights to determine the final FY 2023 relative weights.

You can find the updated relative weights, geometric and arithmetic mean LOS and which MS-DRGs are designated as a post-acute DRG in the Final Rule Table 5.

For FY 2023, MS-DRG 018 (Chimeric antigen Receptor (CAR) T-Cell and Immunotherapies) has the highest relative weight at 36.1452 and MS-DRG 795 (Normal Newborn) has the lowest relative weight at 0.2024.

MS-DRG Refinements

The number of MS-DRGs will remain the same at FY 2022 at 767. Also, there were not as many MS-DRG refinements made FY 2023 as in years past.

Acute Respiratory Distress Syndrome (ARDS)

CMS received a request to reassign cases reporting diagnois code J80 (Acute respiratory distress syndrome) as the principal diagnosis from MS-DRG 204 (Respiratory Signs and Symptoms) to MS-DRG 189 (Pulmonary Edema and Respiratory Failure). The requestor noted that in the ICD-10-CM Tabular List of Diseases, per the Excludes 1 note under category J96 (Respiratory Failure, not elsewhere classified) only code J80 should be assigned when respiratory failure and ARDs are both documented. Currently, a principal diagnosis of J80 groups to MS-DRG 204.

CMS data analysis supported this request and finalized their proposal to reassign cases with ARDS (code J80) as the principal diagnosis from MS-DRG 204 to MS-DRG 189.

Claims Analysis

In Calendar Year (CY) 2021, in the RealTime Medicare Database (RTMD) database, there were 255 claims sequenced to MS-DRG 204 (Respiratory Signs and Symptoms) with a principal diagnosis of J80 (ARDS). Based on the CMS FY 2022 Final Rule, the shift from MS-DRG 204 to MS-DRG 189 would result in:

• An increase in the MS-DRG Relative Weight (R.W.) of 0.4325, and
• An increase in the MS-DRG National Average Payment of $2,612.56.

For the 255 claims with a principal diagnosis of J80 (ARDS) in CY 2021, the reassignment to MS-DRG 189 would result in a $666,202.80 increase in payment for this group of claims.

Cardiac Mapping

CMS identified a replication issue from ICD-9 based MS-DRGs to ICD-10 based MS-DRGs for procedure code 02K80ZZ (Map conduction mechanism, open approach). Cardiac mapping describes the creation of detailed maps to detect how the electrical signals that control the timing of the heart rhythm move between each heartbeat to identify the location of rhythm disorders. Cardiac mapping is generally performed during open-heart surgery or performed via cardiac catheterization.

This code is currently recognized as a non-O.R. procedure that affects the MS-DRG to which it is assigned. CMS finalized their proposal to reassign this code from MS-DRGs 246, 247, 248, 249, 250, and 251 to MS-DRGs 273 and 274 (Percutaneous and Other Intracardiac Procedures with and without MCC, respectively)

Laparoscopic Cholecystectomy with Common Bile Duct Exploration

A requestor noted that when a laparoscopic cholecystectomy is reported with any one of the listed procedure codes with a common bile duct exploration and gallstone removal procedure that is performed laparoscopically and reported with procedure code 0FC94ZZ, the resulting assignment is MS-DRGs 417, 418 and 419 (Laparoscopic Cholecystectomy without C.D.E. with MCC, with CC, and without CC/MCC, respectively). This MS-DRG assignment does not recognize that a common bile duct exploration (C.D.E.) was performed.

CMS finalized their proposal to redesignate procedure code 0FC94ZZ from a non-O.R. procedure to an O.R. procedure and add it to the logic list for common bile duct exploration (CDE) in MS-DRGs 411, 412, and 413 (Cholecystectomy with C.D.E. with MCC, with CC, and without CC/MCC, respectively).

Claims Analysis

In CY 2021, in the RTMD database, there were 188 claims that sequenced to the MS-DRG group 417, 418, and 419 (Laparoscopic Cholecystectomy without C.D.E. with MCC, with CC, and without CC/MCC respectively) that included the procedure code 0FC94ZZ describing a common bile duct exploration procedure with removal of a gallstone.

Based on the CMS FY 2023 Final Rule, following are the shifts in R.W. and geometric mean LOS by DRG severity levels:

• The increase from MS-DRG 417 to MS-DRG 411 (Chlecystectomy w/C.D.E. w/MCC) in R.W. is 1.0005 and the increase in geometric mean LOS is 1.0 day,">link
• The increase from MS-DRG 418 to MS-DRG 412 (Cholecystecomy w/C.D.E. w/CC) in R.W. is 0.6347 and the increase in geometric mean LOS is 1.1 days, and">link
• The increase from MS-DRG 419 to MS-DRG 413 (Cholecystecomy w/C.D.E. w/o CC/MCC) in R.W. is 0.3154 and increase in geometric mean LOS is 0.6 day.

Resources

• CMS FY 2023 IPPS Final Rule CMS Fact Sheet: link
• CMS FY 2023 Final Rule web page: link