The first thing to check in any seizing patient is a bedside glucose test to make sure that hypoglycemia is not the cause.
Indications for Endotracheal Intubation for Seizing the Patient (1)
Absolute indications
1. Hypoxemia (SpO2 < 90%) secondary to hypoventilation or airway obstruction
2. Treatment of underlying etiology (e.g., intracranial bleed with elevated ICP)
3. Prolonged seizure refractory to anticonvulsants (to prevent accumulating metabolic debt [acidosis and rhabdomyolysis])
4. Generalized convulsive status epilepticus
Relative indications
1. Prophylaxis for the respiratory depressant effect of large doses of anticonvulsants (e.g., benzodiazepines and barbiturates)
2. Termination of seizure activity to facilitate diagnostic workup (e.g., CT scanning)
3. Airway protection in prolonged seizures.
Drugs and Dosages (2)
1. Preintubation seizure management
–Lorazepam 0.1 mg per kg intravenously (IV) up to 2 mg per minute
or
–Diazepam 0.1 to 0.3 mg per kg IV up to 5 mg per minute or 0.5 mg per kg per rectum
or
–Midazolam 0.1 to 0.3 mg per kg IV up to 5 mg per minute
THEN
–Phosphenytoin 20 mg per kg (as milligrams of phenytoin equivalent)
2. Induction Agents
–Sodium thiopental 3 mg per kg
or
–Propofol 1.5-2 mg per kg
or
–Midazolam 0.2-0.3 mg per kg
or
–Etomidate 0.3 mg per kg
3. Postintubation sedation and [anti-seizure] therapy
— Midazolam 0.05 to 0.2 mg/kg/hour IV infusion,
or
–Propofol 1 to 5 mg/kg/hour IV infusion
(1) Manual of Emergency Airway Management 4th ed, 2012. RM Walls and MF Murphy. p. 399.
(2) Ibid., p. 402.