G93.1
BillableAnoxic brain damage, not elsewhere classified
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is G93.1 an HCC code?
Yes. G93.1 maps to Coma, Brain Compression/Anoxic Damage under the CMS-HCC V28 risk adjustment model (and Coma, Brain Compression/Anoxic Damage 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 G93.1
For G93.1 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 G93.1 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
G93.1 is the ICD-10-CM diagnosis code for anoxic brain damage, not elsewhere classified. Brain damage resulting from lack of oxygen that is not classified elsewhere, potentially causing permanent neurological impairment. G93.1 sits in the ICD-10-CM chapter for diseases of the nervous system (g00-g99), within the section covering other disorders of the nervous system (g89-g99).
Under the CMS-HCC V28 risk adjustment model, G93.1 maps to Coma, Brain Compression/Anoxic Damage (HCC 202) with a community, non-dual, aged base RAF weight of 0.000. Under the older V24 model, G93.1 mapped to the same category but with a base RAF weight of 0.546 — 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.
Document the cause of anoxia (cardiac arrest, respiratory failure, near-drowning, etc.) in the medical record. Because G93.1 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 G93.1 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Document the cause of anoxia (cardiac arrest, respiratory failure, near-drowning, etc.) in the medical record
- •Use this code only when the anoxic damage cannot be classified to a more specific condition
Clinical Significance
Anoxic brain damage not elsewhere classified represents significant irreversible brain injury caused by oxygen deprivation, often following cardiac arrest, near-drowning, or severe respiratory failure. This diagnosis carries major implications for patient prognosis, functional status, and long-term care needs. It is a high-severity condition that significantly impacts resource utilization and risk adjustment.
Documentation Requirements
- ✓Clear documentation of the anoxic event (cardiac arrest, respiratory failure, near-drowning, etc.)
- ✓Neurological examination findings documenting the extent of brain damage
- ✓Imaging (CT or MRI) showing evidence of hypoxic-ischemic injury
- ✓Functional status assessment including Glasgow Coma Scale or similar scoring
- ✓Prognosis documentation and ongoing management plan (rehabilitation, long-term care needs)