186 MS-DRG: PLEURAL EFFUSION WITH MCC
MS-DRG 186 groups Medicare inpatient hospital stays for: PLEURAL EFFUSION WITH MCC. This is a medical MS-DRG. It falls under MDC 04 (Diseases and Disorders of the Respiratory System).
Payment & Classification Data
Official CMS values from the FY2027 IPPS Final Rule Table 5.
| Major Diagnostic Category | MDC 04 — Diseases and Disorders of the Respiratory System |
| DRG Type | Medical |
| Severity Level | MCC |
| Relative Weight | 1.5835 |
| Relative Weight (10% Cap Applied) | 1.5835 |
| Geometric Mean Length of Stay | 4.2 days |
| Arithmetic Mean Length of Stay | 5.6 days |
| Post-Acute Transfer DRG | Yes |
| Special Pay Transfer DRG | No |
Defining Codes (FY2027)
5 diagnosis codes can drive assignment here: J90, J91.8, J94.0, J94.2, J94.8.
From the CMS MS-DRG Definitions Manual (Appendices B and E). Assignment also depends on severity, discharge status and the rest of the claim.
Contextual Map
Every relationship of 186 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.
Major Diagnostic Category
- MDC 04 — Diseases and Disorders of the Respiratory System[MDC]— CMS MS-DRG Definitions Manual · FY2027
Defining diagnoses
- J90 — Pleural effusion, not elsewhere classified[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- J91.8 — Pleural effusion in other conditions classified elsewhere[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- J94.0 — Chylous effusion[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- J94.2 — Hemothorax[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
- J94.8 — Other specified pleural conditions[Grouper diagnosis]— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
DRG family
- DRG 187 — PLEURAL EFFUSION WITH CC[DRG family]: “PLEURAL EFFUSION WITH CC — same CMS DRG family (186-188), split by severity.”— CMS MS-DRG Definitions Manual (DRG family 186-188) · FY2027
- DRG 188 — PLEURAL EFFUSION WITHOUT CC/MCC[DRG family]: “PLEURAL EFFUSION WITHOUT CC/MCC — same CMS DRG family (186-188), split by severity.”— CMS MS-DRG Definitions Manual (DRG family 186-188) · FY2027
Read from: CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v44. All data sources · How to read the labels · How MedCoder verifies its implementation
Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 20, 2026 · All releases and sources