2026 ICD-10-CM Diagnosis Code S36.81XDInjury of peritoneum, subsequent encounter
S36.81XD is a billable ICD-10-CM diagnosis code for injury of peritoneum, subsequent encounter. The 7th character D marks it as a subsequent encounter code, used during routine care in the healing or recovery phase. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 949 through 950. The code is exempt from POA reporting. Coders also document this condition as injury of peritoneum. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Internal organ injury, subsequent encounter.
Code Identity
Code Classification
Present on Admission (POA)Billing
S36.81XD is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Injury of peritoneum
- Injury of peritoneum without open wound into abdominal cavity
- Peritoneal foreign body
- Peritoneum injury with open wound into cavity
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Injury of intra-abdominal organs (S36). Use the following options for the applicable episode of care:
- A - initial encounter
- D - subsequent encounter
- S - sequela
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Peritoneal Disorders
Your peritoneum is the tissue that lines your abdominal wall and covers most of the organs in your abdomen. A liquid, peritoneal fluid, lubricates the surface of this tissue.
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Convert S36.81XD to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S36.81XDOverview
Is S36.81XD (Injury of peritoneum) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report injury of peritoneum, subsequent encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character D in S36.81XD mean?
The final character D marks a subsequent encounter: use it for routine care while the injury of peritoneum is healing, after active treatment has ended.
What MS-DRG does S36.81XD group to?
When injury of peritoneum, subsequent encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 949, 950, with relative weights from 0.6277 to 1.1897 depending on complications. Higher weights mean higher Medicare reimbursement.
Is S36.81XD exempt from POA reporting?
Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for injury of peritoneum, subsequent encounter on inpatient claims.
What is the ICD-9 equivalent of S36.81XD?
Under the General Equivalence Mappings, injury of peritoneum, subsequent encounter converts to ICD-9-CM V58.89 (other specfied aftercare). The mapping is approximate, so confirm the match fits the documentation.
Footnotes
[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.
