P91.823
BillableNeonatal cerebral infarction, bilateral
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is P91.823 an HCC code?
Yes. P91.823 maps to Ischemic or Unspecified Stroke under the CMS-HCC V28 risk adjustment model (and Ischemic or Unspecified Stroke under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for P91.823
For P91.823 to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed P91.823 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
P91.823 is the ICD-10-CM diagnosis code for neonatal cerebral infarction, bilateral. A newborn's stroke affecting both sides of the brain simultaneously, caused by blocked blood flow to brain tissue on both hemispheres. P91.823 sits in the ICD-10-CM chapter for certain conditions originating in the perinatal period (p00-p96), within the section covering other disorders originating in the perinatal period (p90-p96).
Under the CMS-HCC V28 risk adjustment model, P91.823 maps to Ischemic or Unspecified Stroke (HCC 249) with a community, non-dual, aged base RAF weight of 0.289. Under the older V24 model, P91.823 mapped to the same category but with a base RAF weight of 0.262 — V28 recalibrated weights across the entire model. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
This code indicates bilateral involvement; confirm documentation clearly states infarction on both sides. Because P91.823 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for P91.823 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This code indicates bilateral involvement; confirm documentation clearly states infarction on both sides
- •Bilateral strokes in neonates are serious and typically require documentation of significant clinical impact
Clinical Significance
Bilateral neonatal cerebral infarction represents devastating stroke affecting both brain hemispheres, indicating extremely poor prognosis. This diagnosis carries the highest risk for severe cerebral palsy, profound developmental delays, and lifelong disability requiring maximal care support.
Documentation Requirements
- ✓Documentation of cerebral infarction affecting both brain hemispheres
- ✓Neuroimaging clearly showing bilateral infarct patterns
- ✓Clinical signs of severe neurological compromise
- ✓Timing and circumstances of bilateral stroke occurrence
- ✓Underlying systemic conditions predisposing to bilateral stroke
- ✓Extent of tissue damage on both sides documented
- ✓Response to emergency interventions
- ✓Prognosis and family counseling documentation