R40.2A

Billable

Nontraumatic coma due to underlying condition

HCC Category Mapping

V28HCC 202 — Coma, Brain Compression/Anoxic Damage

0.000

V24HCC 80 — Coma, Brain Compression/Anoxic Damage

0.546

ESRDHCC 80 — Coma, Brain Compression/Anoxic Damage

0.000

What This Code Means

A state of complete unconsciousness caused by an underlying medical condition rather than head trauma.

Coding Tips

•Use this code when coma is due to conditions like hypoglycemia, stroke, infection, or metabolic disorders
•Code the underlying condition as the primary diagnosis when possible; this code describes the manifestation

Clinical Significance

Nontraumatic coma due to underlying condition indicates profound unconsciousness caused by medical conditions rather than trauma, representing severe illness requiring intensive care management. This specific code provides better clinical precision than unspecified coma and helps identify the medical nature of the unconscious state.

Documentation Requirements

✓Documentation of coma state
✓Underlying medical condition identified
✓Non-traumatic etiology confirmed
✓Glasgow Coma Scale scores
✓Neurological assessment findings
✓Medical conditions causing the coma
✓Response to treatment of underlying condition
✓Duration and progression of coma

Excludes 1 — Do NOT code together

coma scale, best motor response (R40.24.-)
coma scale, best verbal response (R40.22.-)
coma scale, eyes open (R40.21.-)
Glasgow coma scale, total score (R40.23.-)

Code First

underlying condition

Commonly Confused Codes

R40.20 — Unspecified coma when underlying condition is documented S06.9 — Traumatic brain injury coma is traumatic, not nontraumatic R40.3 — Persistent vegetative state is different consciousness level G93.1 — Anoxic brain damage may be the specific underlying condition

Code Hierarchy

└R40Somnolence, stupor and coma └R40.2Coma └R40.2ANontraumatic coma due to underlying condition

└R40.2ANontraumatic coma due to underlying condition