Primary blast injury of brain, NEC LOC status unknown, subs

This code signifies a brain injury resulting directly from the overpressure wave of an explosion, not otherwise specified, where the duration of any associated loss of consciousness is not documented. It indicates that the patient is receiving follow-up care for this specific injury after the initial treatment.

Apply this code for patients presenting for subsequent evaluation or treatment of a primary blast brain injury when the initial acute care has concluded. Documentation must clearly state a primary blast mechanism and an unknown duration of loss of consciousness, and that this is not the initial encounter for the injury.

• Ensure documentation specifies "primary blast injury" and not other types of traumatic brain injury (e.g., impact, penetrating).
• Verify the encounter is for follow-up care; use an acute code for the initial encounter.
• Confirm that the duration of loss of consciousness is explicitly stated as "unknown" in the medical record.