Do you administer the induction agent, such as etomidate (induction agent), then neuromuscular blockade, like succinylcholine (neuromuscular blocking agent), during rapid sequence intubation?

Administration Order for Rapid Sequence Intubation: Induction Agent First, Then Neuromuscular Blockade

During rapid sequence intubation (RSI), the induction agent should be administered first, immediately followed by the neuromuscular blocking agent. 1 This sequential administration optimizes intubating conditions while minimizing risks of awareness during paralysis.

Evidence-Based Rationale

The Society of Critical Care Medicine's 2023 clinical practice guidelines for RSI strongly recommend administering a neuromuscular blocking agent (NMBA) when a sedative-hypnotic induction agent is used for intubation (strong recommendation, low quality of evidence). 1

The proper sequence is:

1. Administer sedative-hypnotic induction agent (e.g., etomidate)
2. Immediately follow with neuromuscular blocking agent (e.g., succinylcholine or rocuronium)

This sequence ensures:

• Patient is adequately sedated before paralysis occurs
• Minimizes risk of awareness during paralysis
• Optimizes intubating conditions

Clinical Benefits of This Approach

Studies demonstrate that using an NMBA following induction significantly improves first-pass success rates:

• 80.9% first-pass success with NMBA vs. 69.6% without NMBA (p=0.003) 1
• Using an NMBA was associated with an odds ratio of 2.37 (95% CI, 1.36-4.88) for first-pass success 1

Medication Selection and Dosing

Induction Agents:

• Etomidate: 0.2-0.3 mg/kg IV 2, 3
• Ketamine: 1-2 mg/kg IV 2
• Propofol: Consider only in hemodynamically stable patients

Neuromuscular Blocking Agents:

• Succinylcholine: 1.5 mg/kg IV (first-line for most RSI scenarios) 2
• Rocuronium: 0.9-1.2 mg/kg IV (when succinylcholine is contraindicated) 2

Common Pitfalls to Avoid

1. Administering NMBA before induction agent: This creates risk of awareness during paralysis, which can be traumatic for patients

2. Delayed administration of NMBA after induction: May result in suboptimal intubating conditions as the peak effect of medications may not align properly

3. Underdosing either medication: Inadequate dosing can lead to poor intubating conditions and increased risk of complications 2

4. Not accounting for hemodynamic effects: Have vasopressors readily available, especially when using agents with greater hemodynamic effects 2

Special Considerations

• In patients with shock or sepsis, etomidate may produce less hypotension than ketamine according to some retrospective evidence 4

• The combination of etomidate and s-ketamine has been shown to produce excellent intubating conditions when followed by rocuronium 5

• For pediatric patients, etomidate (0.3 mg/kg) followed by rocuronium or succinylcholine has become increasingly popular due to its favorable hemodynamic profile 6, 7

By following this evidence-based sequence of administering the induction agent first, followed immediately by the neuromuscular blocking agent, clinicians can optimize intubating conditions while prioritizing patient safety and successful airway management.