T32.73
BillableCorrosions involving 70-79% of body surface with 30-39% third degree corrosion
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is T32.73 an HCC code?
Yes. T32.73 maps to Severe Skin Burn or Condition under the CMS-HCC V28 risk adjustment model (and Severe Skin Burn or Condition 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 T32.73
For T32.73 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 T32.73 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
T32.73 is the ICD-10-CM diagnosis code for corrosions involving 70-79% of body surface with 30-39% third degree corrosion. A severe chemical burn affecting 70-79% of the body surface, with the deepest burns (third degree) covering 30-39% of the affected area. This is a life-threatening injury requiring immediate emergency care. T32.73 sits in the ICD-10-CM chapter for injury, poisoning and certain other consequences of external causes (s00-t88), within the section covering burns and corrosions of multiple and unspecified body regions (t30-t32).
Under the CMS-HCC V28 risk adjustment model, T32.73 maps to Severe Skin Burn or Condition (HCC 385) with a community, non-dual, aged base RAF weight of 0.350. Under the older V24 model, T32.73 mapped to the same category but with a base RAF weight of 0.517 — 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.
Always code both the extent of total body surface involvement and the percentage of third-degree burns for accurate severity assessment. Because T32.73 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 T32.73 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Always code both the extent of total body surface involvement and the percentage of third-degree burns for accurate severity assessment
- •These codes require a seventh character for episode of care (A for initial, D for subsequent, S for sequela)
Clinical Significance
This represents catastrophic chemical burns affecting 70-79% of the body with extensive full-thickness destruction (30-39% third-degree), indicating life-threatening injury with extremely high mortality risk. These patients require immediate burn center intervention with aggressive surgical management and face significant risk of death or severe permanent disability.
Documentation Requirements
- ✓Total body surface area (70-79%)
- ✓Third-degree burn extent (30-39%)
- ✓Chemical agent and exposure details
- ✓Injury timeline and circumstances
- ✓Current treatment phase
- ✓Anatomical distribution
- ✓Associated organ dysfunction
- ✓Multiple surgical procedures