2026 ICD-10-CM Diagnosis Code P91.0Neonatal cerebral ischemia
ICD-10-CM Codes›P00–P96›P90-P96›P91
- Billable — Valid for Submission
- MCC — Major Complication or Comorbidity
- Risk Adjusts — HCC 202
- Not Chronic
P91.0 is a billable ICD-10-CM diagnosis code for neonatal cerebral ischemia. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 791, 793. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 13 closely related codes. Coders also document this condition as acute cerebral ischemia. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Neonatal cerebral disorders.
For Medicare Advantage risk adjustment, P91.0 maps to CMS-HCC Category 202 (Coma, Brain Compression/Anoxic Damage) under the V28 model, adding a risk factor of about 0.543 for a community, non-dual, aged beneficiary in payment year 2026.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
P91.0 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2026.
Source: CMS Payment Year 2026 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Acute cerebral ischemia
- Acute cerebrovascular insufficiency
- Brain stem ischemia
- Cerebral ischemia
- Epilepsy due to perinatal cerebral ischemia
- Neonatal cerebral ischemia
- Perinatal cerebral ischemia
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Type 1 Excludes
- Neonatal cerebral infarction P91.82
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Stroke
A stroke happens when there is a loss of blood flow to part of the brain. Your brain cells cannot get the oxygen and nutrients they need from blood, and they start to die within a few minutes. This can cause lasting brain damage, long-term disability, or even death.
The full article covers:
- What is a stroke?
- What are the types of stroke?
- Who is at risk for a stroke?
- What are the symptoms of a stroke?
- How are strokes diagnosed?
- What are the treatments for stroke?
- Can strokes be prevented?
Read the full article at MedlinePlus
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Convert P91.0 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About P91.0Overview
What is the ICD-10 code for neonatal cerebral ischemia?
The ICD-10-CM code for neonatal cerebral ischemia is P91.0 (sometimes written as P910). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is P91.0 (Other disturbances of cerebral status of newborn) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report neonatal cerebral ischemia on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does P91.0 group to?
When neonatal cerebral ischemia is the principal diagnosis on an inpatient stay, it groups to MS-DRG 791, 793, with relative weights from 4.0590 to 4.1696 depending on complications. Higher weights mean higher Medicare reimbursement.
Is P91.0 a CC or MCC?
CMS lists P91.0 as an MCC (major complication or comorbidity) for FY 2026. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 13 closely related codes in its exclusion list.
What is the ICD-9 equivalent of P91.0?
Under the General Equivalence Mappings, neonatal cerebral ischemia converts to ICD-9-CM 779.2 (cns dysfunction syn NB). The mapping is approximate, so confirm the match fits the documentation.
What HCC is P91.0?
P91.0 (neonatal cerebral ischemia) maps to CMS-HCC Category 202 (Coma, Brain Compression/Anoxic Damage), commonly written as HCC 202, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It does not map to any RxHCC in the Part D prescription drug model.
Does P91.0 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, P91.0 adds a risk adjustment factor of about 0.543 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.097 to 0.721 depending on the payment segment). A more severe related category (HCC 63, HCC 397, and HCC 398) supersedes it when both are reported. See the full factor table on the HCC 202 category page.
