2 of 19
From the Greek koma, meaning "deep sleep"
It is an alteration of consciousness in which a person
appears to be asleep, cannot be aroused even by
painful stimuli, and shows no awareness of the
Acute life-threatening neurological emergency
Requires prompt intervention for preservation of life
& brain function
Disorders of Consciousness
3 of 19
Lethargy: difficulty maintaining an aroused state,
can be aroused with little difficulty
Obtundation: decreased arousal but responsive to
stimuli, cannot fully be aroused
Stupor: responsiveness to pain but not to other
Coma: unresponsive even to painful stimuli
4 of 19
Complete paralysis: locked-in state, GBS, botulism
Akinetic-mutism: frontal lobe lesions, tone &
5 of 19
Consciousness can be diminished or abolished by
Dysfunction within the brainstem
Impairment of both cerebral hemispheres
Insults that globally depress neuronal activity (e.g.
Unilateral cerebral lesions may cause coma if they
compress or injure contralateral or brainstem
7 of 19
Subclinical status epilepticus
Arterial ischemic stroke
Cerebral sinovenous thrombosis
Hyponatremia or its correction
Hypernatremia or its correction
Hyperosmolality or its correction
Vital signs and general and trauma examination
Neurologic examination and GCS
Screening laboratories (CBC, glucose, electrolytes, BUN, creatinine, blood
8 of 19
cultures, LFTs, urinalysis, urine drug screen)
Head CT scan: do emergently if focal neurologic signs, papilledema, fever -
consider rapid MRI instead if available.
Lumbar puncture: do emergently after CT scan if fever, elevated WBC,
meningismus; otherwise do according to level of suspicion for diagnosis or
if cause remains obscure
Other laboratory tests: for metabolic conditions, coagulation tests,
carboxyhemoglobin, specific drug concentrations - do according to level of
suspicion for diagnosis or if cause remains obscure
EEG: for possible nonconvulsive seizure, or if diagnosis remains obscure
Brain MRI with DWI, if cause remains obscure
9 of 19
Size Possible interpretation
Normal eye with two pupils equal in size and reactive to light.
This means that the patient is probably not in a coma and is
probably lethargic, under influence of a drug, or sleeping.
Pinpoint pupils: opiate overdose, damage to pons. The pinpoint
pupils are still reactive to light, bilaterally.
One pupil is dilated and unreactive, while the other is normal.
Damage to the oculomotor nerve or possibility of vascular
Both pupils are dilated and unreactive to light. This could be
due to overdose of certain medications, hypothermia or
13 of 19
Intubate if GCS ≤8 or respiratory failure
Stabilize cervical spine
Blood pressure support as needed
Dextrose 0.25 g/kg (2.5 mL/kg of 10 % dextrose solution)
Treat definite seizures. Lorazepam (0.1 mg/kg, maximum
single dose 5 mg). If seizures continue treat as for status
14 of 19
Ceftriaxone 100 mg/kg (maximum single dose 2
grams) and Vancomycin
Naloxone 0.1 mg/kg IV; maximum 2 mg IV (use if
opioid toxidrome: miosis, respiratory depression, hypotonia)
Mannitol 0.5 - 1 gram/kg IV
15 of 19
Largely specific to the etiology
Mortality rates according to a study in England:
near-drowning - 84%
infection - 60%
metabolic causes 27%
intoxication - 3.4%
16 of 19
Coma is transient, patients either recover, die or go into a more
permanent state of impaired consciousness
Persistent vegetative state (PVS): permanent if lasts > 12
mo after traumatic injury or > 3 mo after non-traumatic
Minimally conscious state: severe alteration in
consciousness who do not meet criteria for PVS
Brain death: coma, apnea, and absent brainstem reflexes.
No chance of recovery, synonymous with death in most
Persistent Vegetative State (PVS)
17 of 19
No evidence of awareness of self or environment and no ability
to interact with others.
No evidence of sustained, reproducible, purposeful, or
voluntary behavioral responses to visual, auditory, tactile, or
No evidence of language comprehension or expression.
Intermittent wakefulness manifested by the presence of sleep-wake
Sufficiently preserved hypothalamic and brainstem autonomic
function to permit survival with medical and nursing care.
Bowel and bladder incontinence.
Variably preserved cranial nerve reflexes and spinal reflexes.
19 of 19
1. Nelson Essentials of Pediatrics, 7e – 2015
2. The Harriet Lane Handbook, 20e - 2015
3. Plum & Posner's Diagnosis of Stupor & Coma, 4e –
4. Evaluation of stupor & coma in children. In:
UpToDate, Post, TW (Ed), UpToDate, Waltham, MA,
5. Coma on Wikipedia