In simple words: A coma is a deep state of unconsciousness where a person is alive but cannot be woken up and doesn't respond to their surroundings.

A coma is a state of profound unconsciousness in which a person cannot be awakened and does not respond normally to stimuli, light, or sound.It is a severe reduction in mental function due to structural, physiological, or metabolic impairment of the brain.

Example 1: A patient is brought to the emergency room after a motor vehicle accident. They are unresponsive to stimuli and are diagnosed with an unspecified coma due to a traumatic brain injury where the Glasgow coma scale is not documented., A patient with a history of drug abuse is found unconscious at home. There is no evidence of trauma, and laboratory tests are pending. The patient is diagnosed with an unspecified coma pending further investigation., A patient with a history of diabetes presents with altered mental status and eventually becomes unarousable. Since coma due to diabetic ketoacidosis or nonketotic hyperosmolar coma has explicit ICD-10-CM codes, the provider documents “unspecified coma” until more definitive test results confirm or refute the underlying diabetic causes of the coma.

Documentation should include: the level of consciousness using standardized terms (e.g., unresponsive, obtunded, stupor); any preceding events or symptoms; results of neurological examination; relevant diagnostic testing (e.g., Glasgow Coma Scale, imaging studies, blood tests); and suspected underlying cause, if known.

** For cases of traumatic brain injury with coma and a documented coma scale, report the specific coma scale code instead of the unspecified code.