What are the recommended drugs and dosages for rapid sequence intubation in adult patients, including induction agents, analgesics, and paralytic agents?

Rapid Sequence Intubation: Drugs and Dosages for Adult Patients

Always administer a sedative-hypnotic induction agent when using a neuromuscular blocking agent (NMBA) for intubation, even in hemodynamically unstable patients with depressed consciousness. 1

Induction Agents (Sedative-Hypnotics)

Agent Selection and Dosing

Choose etomidate, ketamine, propofol, or midazolam based on hemodynamic status, as there is no mortality difference between agents:

• Etomidate: 0.2–0.3 mg/kg (or 0.15 mg/kg in hemodynamically compromised patients) 1

  • Most hemodynamically stable option
  • No increased mortality compared to other agents despite adrenal enzyme inhibition concerns 1
  • Preferred when hemodynamic stability is paramount

• Ketamine: 2 mg/kg 1

  • Quick onset with sympathomimetic properties
  • Preserves respiratory drive
  • Caution: May cause hypotension in critically ill patients with depleted catecholamine stores 1

• Propofol: 2.0 mg/kg 2

  • Quick onset and short duration
  • Most profound blood pressure effect—limit use in critically ill patients 1

• Midazolam: Standard RSI doses 1

  • Longer onset than etomidate/ketamine
  • Potent venodilator at RSI doses—less desirable for hemodynamically unstable patients 1

Critical Dosing Consideration

The weight-based sedative dose (within standard ranges) is NOT independently associated with postintubation hypotension for etomidate or ketamine. 3 This means dose reduction below standard ranges to prevent hypotension is not evidence-based, though expert opinion has traditionally recommended this practice.

Analgesics (Opioids)

• Alfentanil: 10–12.5 μg/kg 2, 4

  • Rapid onset, commonly used as adjunct
  • Attenuates intubation response when combined with induction agents 4

• Fentanyl: 3 μg/kg 1

  • Alternative opioid for RSI sequence
  • Used in combination protocols with ketamine and rocuronium 1

Neuromuscular Blocking Agents (Paralytics)

Agent Selection and Dosing

Succinylcholine remains the gold standard for first-attempt intubation success:

• Succinylcholine: 1.0–1.5 mg/kg 1, 5

  • Fastest onset of all NMBAs
  • Superior first-attempt intubation success rate (79.4%) compared to rocuronium (74.6%) 5
  • Associated with several adverse events not seen with rocuronium 5

• Rocuronium: 0.6–1.2 mg/kg 1, 5, 2

  • Standard dose: 1.0–1.2 mg/kg for rapid sequence intubation 1, 5
  • Lower dose option: 0.6 mg/kg provides acceptable intubation conditions at 60 seconds when combined with appropriate induction agents 2, 4
  • Failed to demonstrate noninferiority to succinylcholine for first-attempt success 5
  • Preferred when succinylcholine is contraindicated

Timing Considerations

Laryngoscopy timing affects success with lower NMBA doses:

• For rocuronium 0.5 mg/kg (1.5× ED95), delay laryngoscopy to 75 seconds after administration to achieve satisfactory intubation conditions 2
• Standard timing of 60 seconds is adequate for rocuronium 0.6 mg/kg when combined with etomidate or thiopental 4

Clinical Pearls and Pitfalls

Key Practice Points:

• Never omit the sedative-hypnotic agent, even in hemodynamically unstable or obtunded patients—this is a best practice statement from the Society of Critical Care Medicine 1

• Etomidate combined with etomidate (versus thiopental) provides superior attenuation of intubation response when used with alfentanil and rocuronium 4

• Peri-intubation hypotension is common (16.2% with etomidate, 29.0% with ketamine) and associated with organ dysfunction, prolonged mechanical ventilation, ICU stay, and increased mortality 1, 3

• The choice between etomidate and other induction agents should be based on hemodynamic profile preferences rather than mortality concerns, as no mortality difference exists between agents 1