MS-DRG · FY 2026 v43.0

MS-DRG 199 – Pneumothorax with MCC

A Medical DRG in MDC 04 (Diseases & Disorders of the Respiratory System). Inpatient cases group to DRG 199 when the ICD-10-CM principal diagnosis is one of the 14 codes listed below and a secondary diagnosis on the major complication or comorbidity (MCC) list is present. Its FY 2026 relative weight is 1.7641 with a geometric mean length of stay of 4.8 days.

Medical DRG – assigned by principal diagnosis✓ Official CMS v43.0 dataset
1.7641
Relative Weight
4.8
Geometric Mean LOS (days)
6.3
Arithmetic Mean LOS (days)
14
Principal Diagnosis Codes

Severity family

DRG 199with MCCWeight 1.7641 · GMLOS 4.8 daysDRG 200with CCWeight 1.0993 · GMLOS 3.1 daysDRG 201without CC/MCCWeight 0.7151 · GMLOS 2.3 days
How a case is assigned to DRG 199

The grouper first assigns the case to MDC 04 from the principal diagnosis and finds no qualifying operating-room procedure (this is a Medical DRG; ICD-10-PCS codes do not drive assignment here), then applies the severity split from secondary diagnoses: with MCC → 199; with CC → 200; without CC/MCC → 201.

ICD-10-CM

Principal Diagnosis Codes 14 codes · 5 categories

14 of 14 shown
J93 Pneumothorax and air leak7 codes
  • J93.0 Spontaneous tension pneumothorax
  • J93.11 Primary spontaneous pneumothorax
  • J93.12 Secondary spontaneous pneumothorax
  • J93.81 Chronic pneumothorax
  • J93.82 Other air leak
  • J93.83 Other pneumothorax
  • J93.9 Pneumothorax, unspecified
J95 Intraoperative and postprocedural complications and disorders of respiratory system, not elsewhere classified2 codes
J98 Other respiratory disorders1 code
  • J98.2 Interstitial emphysema
S27 Injury of other and unspecified intrathoracic organs3 codes
  • S27.0XXA Traumatic pneumothorax, initial encounter
  • S27.1XXA Traumatic hemothorax, initial encounter
  • S27.2XXA Traumatic hemopneumothorax, initial encounter
T79 Certain early complications of trauma, not elsewhere classified1 code
  • T79.7XXA Traumatic subcutaneous emphysema, initial encounter
ICD-10-PCS

Procedure Codes

Procedure codes do not drive assignment for this DRG. DRG 199 is a Medical DRG, assigned from the principal diagnosis above.

Frequently Asked Questions

What is MS-DRG 199?

MS-DRG 199 (Pneumothorax with MCC) is a medical DRG in MDC 04 (Diseases & Disorders of the Respiratory System). Its FY 2026 relative weight is 1.7641 with a geometric mean length of stay of 4.8 days.

What is the difference between DRG 199, 200, 201?

All 3 share the same base category; the severity of secondary diagnoses separates them: 199 (with MCC), 200 (with CC), 201 (without CC/MCC). A major complication or comorbidity (MCC) places the case in the highest-weighted DRG of the family; a CC in the middle; neither in the lowest.

How many diagnosis codes group to DRG 199?

14 ICD-10-CM principal diagnosis codes group to this DRG, spanning 5 three-character categories.

What is the relative weight of DRG 199?

The FY 2026 relative weight of this DRG is 1.7641, meaning reimbursement of roughly 1.76 times the average Medicare inpatient case. Multiply by a hospital's blended base rate for the approximate payment.

← PreviousDRG 198 – Interstitial Lung Disease without CC/MCC
Source: CMS ICD-10 MS-DRG v43.0 Definitions Manual and the FY 2026 IPPS Final Rule (Table 5), effective October 1, 2025 through September 30, 2026. We publish the DRG assignments as CMS defines them and add the navigation, search, and code links.