What sedation medication is recommended for rapid sequence intubation (RSI)?

Sedation Medication Selection for Rapid Sequence Intubation

For rapid sequence intubation (RSI) in critically ill adults, etomidate (0.3 mg/kg IV) or ketamine (1-2 mg/kg IV) are recommended as first-line sedative-hypnotic agents, with etomidate being preferred in hemodynamically unstable patients due to its favorable hemodynamic profile. 1, 2, 3

Primary Sedative Options

Etomidate

• Recommended dose: 0.3 mg/kg IV 1, 3
• Preferred in hemodynamically unstable patients due to minimal cardiovascular effects 1, 4
• No difference in mortality or vasopressor requirements compared to other induction agents 1
• Quick onset (5-15 seconds) and short duration of action (5-15 minutes) 4
• May cause transient adrenal suppression, but corticosteroid administration following etomidate is not routinely recommended 1

Ketamine

• Recommended dose: 1-2 mg/kg IV 2, 3
• Alternative first-line agent with sympathomimetic properties that help maintain hemodynamic stability 2, 3
• Quick onset and short duration of action with preservation of respiratory drive 2
• In patients with depleted catecholamine stores, ketamine may paradoxically cause hypotension despite its sympathomimetic properties 3

Neuromuscular Blocking Agent (NMBA) Considerations

• A sedative-hypnotic agent MUST be administered before the NMBA to prevent awareness during paralysis 1, 2, 3
• Recommended NMBAs include:
  • Succinylcholine (1-1.5 mg/kg IV) - first-line when no contraindications exist 3
  • Rocuronium (0.9-1.2 mg/kg IV) - alternative when succinylcholine is contraindicated 3, 5
• Using an NMBA significantly improves first-pass success rates (80.9% with NMBA vs. 69.6% without) 1

Clinical Decision Algorithm

1. Assess hemodynamic stability:

   • If hemodynamically unstable (SBP < 90 mmHg): Use etomidate 0.3 mg/kg IV 1, 4
   • If hemodynamically stable: Either etomidate 0.3 mg/kg IV or ketamine 1-2 mg/kg IV 1, 2, 3

2. Consider special circumstances:

   • For patients with head injury: Etomidate is preferred due to its cerebroprotective effects 4
   • For patients with bronchospasm: Consider ketamine for its bronchodilatory effects 2

3. Administer appropriate NMBA after sedative:

   • Succinylcholine 1-1.5 mg/kg IV (if no contraindications) 3
   • Rocuronium 0.9-1.2 mg/kg IV (if succinylcholine contraindicated) 3, 5

Important Clinical Pearls

• Recent evidence suggests that the dose of etomidate or ketamine is not independently associated with post-intubation hypotension, challenging the traditional practice of dose reduction in hemodynamically unstable patients 6
• Ensure full neuromuscular blockade before attempting intubation to prevent coughing or movement that could increase the risk of aspiration 3
• Have vasopressors immediately available for managing potential hypotension during RSI 3
• When using high-dose rocuronium (≥0.9 mg/kg), have sugammadex available for reversal if needed in a "can't intubate, can't ventilate" scenario 3
• Position the patient in semi-Fowler position during RSI to improve first-pass intubation success and reduce risk of aspiration 3

Common Pitfalls to Avoid

• Administering NMBA before sedative agent, which can lead to awareness during paralysis (occurs in approximately 2.6% of emergency department intubations) 2
• Underdosing sedative agents in hemodynamically unstable patients - recent evidence suggests this may not prevent post-intubation hypotension 6
• Failure to wait for full neuromuscular blockade before attempting intubation 3
• Not having appropriate reversal agents available when using rocuronium 3