Knowledge Base Article

The FY 2024 IPPS Final Rule (CMS-1785-F) was issued August 1, 2023. This article focuses on final changes to Medicare Severity Diagnosis-Related Group (MS-DRG) classifications in Major Diagnostic Categories (MDCs) 02, 04, and 06 (Diseases and Disorders of the Eye, Respiratory System, and Digestive System, respectively).

MDC 02: Diseases and Disorders of the Eye: Retinal Artery Occlusion

A request was made to review the MS-DRG assignment of cases involving central retinal artery occlusion (CRAO). The assertion was that CRAO is a form of acute ischemic stroke which occurs when a vessel supplying blood to the brain is obstructed and there is growing recognition of this diagnosis as a vascular neurological problem. New evidence outlines treatment of patients with CRAO with acute stroke protocols, specifically with intravenous thrombolysis or hyperbaric oxygen therapy, to improve outcomes. Based on this request, data analysis and examining clinical considerations, CMS finalized their proposals to:  

• Reassign ICD-10-CM diagnosis codes H34.10, H34.11, H34.12, H34.13, H34.231, H34.232, H34.233, and H34.239 from MDC 02 MS-DRG 123 to MS-DRGs 124 and 125,
• Add procedure codes describing the administration of a thrombolytic agent listed in this section to MS-DRG 124,
• As part of the logic for MS-DRG 124, designate the administration of thrombolytic agent codes as non-O.R. procedures affecting the MS-DRG, and
• Change the titles of MS-DRGs 124 and 125 from “Other Disorders of the Eye, with and without MCC, respectively,” to “Other Disorders of the Eye with MCC or Thrombolytic Agent, with without MCC, respectively” to better reflect the assigned procedures.

   

  MDC 04: Diseases and Disorders of the Respiratory System: Ultrasound Accelerated Thrombolysis for Pulmonary Embolism

  A request was made to reassign cases reporting ultrasound accelerated thrombolysis (USAT) with administration of thrombolytic(s) for the treatment of pulmonary embolism (PE) from MS-DRGs 166, 167, and 168 (Other Respiratory O.R. Procedures with MCC, with CC, and without CC/MCC, respectively) to MS-DRGs 163, 164, and 165 (Major Chest Procedures with MCC, with CC, and without CC/MCC, respectively).

   

  Clinical and data analyses support creating a new base MS-DRG for cases reporting a principal diagnosis of PE and USAT or standard catheter directed thrombolysis (CDT) procedures with or without thrombolytics. CMS finalized their proposal to create a new MS-DRG 173 (Ultrasound Accelerated and Other Thrombolysis with Principal Diagnosis Pulmonary Embolism).

   

  MDC 04: Respiratory Infections and Inflammations Logic

  There are two logic lists for case assignment to MS-DRGs 177, 178, and 179 (Respiratory Infections and Inflammations with MCC, with CC, without CC/MCC, respectively). All diagnosis codes in the first logic list are designated as MCCs.

   

  Currently, if the principal diagnosis is from the second logic list and any of the diagnoses from the first logic list are also on the claim, the case would be assigned to MS-DRG 177. This is inconsistent with how other similar logic lists function in the ICD-10 grouper software. Therefore, CMS proposed to correct the logic for cases assigned to MS-DRG 177 by excluding the 15 diagnosis codes in the first logic list from acting as an MCC when reported as a secondary diagnosis when the principal diagnosis is from the second logic list.

   

  CMS finalized their proposal with the modification of excluding 11 diagnosis codes in the first logic list from acting as an MCC when any one of the listed codes is reported as a secondary diagnosis with a diagnosis code in the second logic list.

   

  The 11 diagnosis codes includes A48.1 (Legionnaire’s disease), J15.0 (Pneumonia due to Klebsiella pneumoniae), J15.1 (Pneumonia due to Pseudomonas), J15.20 (Pneumonia due staphylococcus, unspecified), J15.211 (Pneumonia due to Methicillin susceptible Staphylococcus aureus), J15.212 (Pneumonia due Methicillin resistant Staphylococcus aureus), J15.29 (Pneumonia due to other staphylococcus), J15.5 (Pneumonia due to Escherichia coli), J15.61 (Pneumonia due to Acinetobacter baumannii), J15.69 (Pneumonia due to other Gram-negative bacteria), and J15.8 (Pneumonia due to other specified bacteria).

   

  The five influenza codes in the first logic list (J10.00, J10.01, J10.08, J11.00, or J11. 08) will continue to be allowed to act as an MCC with a principal diagnosis from the second logic list in specific clinical scenarios.

   

  MDC 06: Diseases and Disorders of the Digestive System: Appendicitis

  ICD-10-CM diagnosis codes K35.20 (Acute appendicitis with generalized peritonitis, without abscess) and K35.21 (Acute appendicitis with generalized peritonitis, with abscess) will no longer be effective October 1, 2023. At that time, six new diagnosis codes describing acute appendicitis with generalized peritonitis, with and without perforation or abscess will become effective. The new codes are assigned to MS-DRGs 371, 372, and 373 (Major Gastrointestinal Disorders and Peritoneal Infections with MCC, with CC, and without MCC/CC, respectively).

   

  CMS notes that clinically both localized and generalized peritonitis in association with an appendectomy require the same level of patient care and believe the distinction between “complicated” versus “uncomplicated” is no longer meaningful regarding resource consumption. After consideration of comments received, CMS finalized their proposals to:

   

• Delete MS-DRGs 338, 339, 340, 341, 342, and 343,
• To create new MS-DRGs 397, 398, and 399 (Appendix Procedures with MCC, with CC, and without CC/MCC, respectively), and
• To no longer require a diagnosis in the definition of the logic for case assignment for the new MS-DRGs.

The finalized changes go into effect October 1, 2023.