R40.2A: Nontraumatic coma due to underlying condition
R40.2A is a billable, specific ICD-10-CM code for nontraumatic coma due to underlying condition. It is valid for submission on a claim.
Check R40.2A with the rest of the claim: free scrubberExcludes1: never code together
These conditions cannot occur together. Billing both on the same encounter is a denial.
Code first
The underlying condition must be sequenced before this code.
- underlying condition
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Secondary coma
Excludes1 inherited from the categories above R40.2A
A category’s note binds every code beneath it.
Other codes that can never be billed with R40.2A
Their own Excludes1 notes name this code, so the conflict is not listed above.
- R41.82Altered mental status, unspecified
Risk adjustment
R40.2A risk-adjusts. Under the CMS-HCC V28 model it maps to this category:
- HCC 202 Coma, Brain Compression/Anoxic Damage0.543 RAF
Coefficient shown for the Community Non-dual Aged segment. A higher HCC in the same hierarchy will suppress this one, so capturing it does not always add score. Look up the whole chart to see which of its HCCs the hierarchy would zero.
Medicare coverage
R40.2A is named in 17 Medicare coverage policies: 17 listing it as supporting medical necessity. Which one applies depends on your Medicare contractor.
- A54799Billing and Coding: Urine Drug Testing
- A55001Billing and Coding: Urine Drug Testing
- A56612Billing and Coding: CT of the Head
- A56625Billing and Coding: Echocardiography
Alphabetic index entries that lead here
- Coma›nontraumatic, due to underlying condition
- Coma›secondary
Code history
Unchanged in every release from FY2024 to FY2027.