What are the recommended doses of medications for emergency intubation in a typical adult patient?

Recommended Medication Doses for Emergency Intubation in Adults

For rapid sequence intubation in a typical adult patient, administer etomidate 0.3 mg/kg IV (or ketamine 1-2 mg/kg IV as an alternative) followed immediately by succinylcholine 1-1.5 mg/kg IV, or rocuronium 1.0-1.2 mg/kg IV when succinylcholine is contraindicated. 1, 2

Induction Agent Selection and Dosing

First-Line: Etomidate

• Etomidate 0.3 mg/kg IV is the preferred induction agent for most adult patients due to its favorable hemodynamic profile 3, 1, 2
• The dose range is 0.2-0.4 mg/kg IV, with 0.3 mg/kg being the standard dose 1, 2
• In hemodynamically compromised patients, consider reducing to 0.15-0.2 mg/kg to minimize cardiovascular effects while maintaining adequate sedation 1
• Critical pitfall: Do not exceed 0.3 mg/kg in elderly patients (>55 years) as higher doses are associated with increased respiratory depression and oxygen desaturation 1

Alternative: Ketamine

• Ketamine 1-2 mg/kg IV is the preferred alternative, especially in hemodynamically unstable patients 3, 1, 2
• Use the lower end of dosing (1 mg/kg) in patients with cardiovascular compromise 1
• Critical warning: In critically ill patients with depleted catecholamine stores (prolonged septic shock, severe cardiogenic shock), ketamine may paradoxically cause hypotension despite its sympathomimetic properties—have vasopressors immediately available 1, 4
• Higher doses (>2 mg/kg) are associated with significantly increased adverse events including hypotension (OR 7.0), laryngospasm (OR 10.8), and failed airway (OR 3.6) 5

Neuromuscular Blocking Agent Selection and Dosing

First-Line: Succinylcholine

• Succinylcholine 1-1.5 mg/kg IV is the first-line paralytic agent when no contraindications exist 3, 1, 2
• Dose based on actual body weight, not ideal body weight 1
• Provides optimal intubating conditions within 60 seconds 6
• Absolute contraindications: hyperkalemia, burns >24 hours old, crush injuries, prolonged immobilization, or neuromuscular disease due to risk of fatal hyperkalemic cardiac arrest 2

Alternative: Rocuronium

• Rocuronium 1.0-1.2 mg/kg IV when succinylcholine is contraindicated 3, 1, 2
• The European Society of Anaesthesiology and Intensive Care recommends 0.9-1.2 mg/kg for rapid sequence intubation 3
• Higher doses (≥1.4 mg/kg) are associated with improved first-attempt success when using direct laryngoscopy (OR 1.9) and in hypotensive patients, with no increase in adverse events 7
• Dose based on actual body weight—dosing by ideal body weight in obese patients results in longer time to maximum block and shorter clinical duration 8
• Critical requirement: Sugammadex must be immediately available for reversal in "can't intubate, can't ventilate" scenarios 3, 1, 2
• Wait at least 60 seconds after rocuronium administration before attempting intubation 1

Timing and Sequence

• Always administer the sedative-hypnotic agent BEFORE the neuromuscular blocking agent to prevent awareness during paralysis 1, 2
• Administer rocuronium as early as practical after induction to minimize apnea time and risk of patient coughing 1
• With rocuronium, ensure full neuromuscular blockade before attempting intubation (60 seconds minimum or confirm with peripheral nerve stimulator) 1

Practical Dosing Examples for a 70 kg Adult

Standard Regimen (Etomidate + Succinylcholine)

• Etomidate: 21 mg IV (0.3 mg/kg × 70 kg)
• Succinylcholine: 105 mg IV (1.5 mg/kg × 70 kg)

Alternative Regimen (Ketamine + Rocuronium)

• Ketamine: 70-140 mg IV (1-2 mg/kg × 70 kg)
• Rocuronium: 70-84 mg IV (1.0-1.2 mg/kg × 70 kg)

Special Population Considerations

Hemodynamically Unstable Patients

• Prefer ketamine 1 mg/kg over etomidate, though both are acceptable 1, 2
• Consider etomidate 0.15-0.2 mg/kg if using etomidate 1
• Have vasopressors immediately available regardless of agent chosen 1, 4

Septic Patients

• Ketamine is strongly preferred over etomidate due to adrenal suppression concerns, though adult data shows no mortality difference 1, 4
• Do not administer corticosteroids following etomidate—multiple RCTs showed no mortality benefit 1

Obese Patients

• Dose all medications based on actual body weight, not ideal body weight 1, 8
• Dosing rocuronium by ideal body weight results in inadequate intubating conditions 8