Medical Council of Canada

Medical expert

Coma - 58-1


Coma, whether transient or persistent, is a state of pathologic unconsciousness. Coma requires urgent evaluation to avoid permanent brain injury or death.

Causal Conditions

(list not exhaustive)
  1. Focal disease (e.g., tumor, stroke)
  2. Diffuse disease
    1. Vascular (e.g., hypertensive encephalopathy, syncope)
    2. Infectious (e.g., meningitis, encephalitis)
    3. Trauma
    4. Metabolic (e.g., uremia, hypercalcemia, hypoglycemia)
    5. Substance use and overdose
  3. Seizures

Key Objectives

Given a patient in coma, the candidate will diagnose the cause, severity, and complications, and will initiate an appropriate management plan. Particular attention should be paid to urgent and emergent conditions.

Enabling Objectives

Given a patient in coma, the candidate will

  1. list and interpret critical clinical findings, including those derived from
    1. a complete history and corroboration of information from appropriate sources;
    2. the identification of most likely causes of coma by means of a complete physical examination including appropriate neurological examination;
    3. the determination of level of consciousness using an appropriate assessment tool (e.g., glasgow coma scale);
  2. list and interpret critical investigations, including
    1. laboratory investigations (e.g., toxin screen, glucose), diagnostic imaging (e.g., computerized tomography, magnetic resonance imaging) and others (e.g., lumbar puncture, electroencephalography);
  3. construct an effective initial management plan, including
    1. initiating urgent care (e.g., airway, breathing, circulation) and appropriate empiric treatment as indicated (narcotic/benzodiazepine reversal, glucose);
    2. instituting immediate treatment as required (e.g., antibiotics, anticonvulsants);
    3. referring the patient for specialized care (e.g., neurosurgery), if necessary;
    4. seeking clarification of proxy decision-making while the patient is incapacitated.
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