R40.4 — Transient alteration of awareness
R40.4 is a billable, specific ICD-10-CM code for transient alteration of awareness. It is valid for submission on a claim.
Risk adjustment
R40.4 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
R40.4 is named in 24 Medicare coverage policies — 24 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A56505Billing and Coding: Transesophageal Echocardiography (TEE)
- A56612Billing and Coding: CT of the Head
- A56619Billing and Coding: Nerve Conduction Studies and Electromyography
- A56625Billing and Coding: Echocardiography
How R40.4 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to R40.4.
- Alteration, Altered›awareness›transient
Related codes at this level
Codes that share R40. If R40.4 is not quite right, the correct code is usually one of these.
Questions about R40.4
- Is R40.4 a billable ICD-10-CM code?
- Yes. R40.4 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does R40.4 sit in the tabular list?
- Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99), in the block Symptoms and signs involving cognition, perception, emotional state and behavior (R40-R46).