Which paralytic agent is preferred for rapid sequence intubation in trauma patients?

Choice of Paralytic Agent in Trauma

Either rocuronium or succinylcholine can be used for rapid sequence intubation in trauma patients when no contraindications to succinylcholine exist, though emerging evidence suggests succinylcholine may offer mortality benefits in general trauma populations while rocuronium appears safer specifically in traumatic brain injury. 1

Primary Recommendation

The 2023 Society of Critical Care Medicine guidelines provide a conditional recommendation that either rocuronium or succinylcholine may be administered for RSI when there are no known contraindications to succinylcholine 1. This reflects low quality evidence with no clear superiority of one agent over the other in most trauma scenarios.

Key Decision Points

For General Trauma Patients:

• Succinylcholine (1 mg/kg) may be preferred based on a 2026 multicenter study of 26,884 patients showing:
  • 3.3% absolute reduction in 60-day mortality (30.1% vs 33.4%, RR 0.901) 2
  • 1.4% absolute reduction in myocardial infarction (10.5% vs 11.9%, RR 0.888) 2
  • Faster onset and shorter duration facilitating more rapid post-intubation sedation 1

For Traumatic Brain Injury (TBI):

• Rocuronium (1.2 mg/kg) is likely safer in severe TBI:
  • Observational data showed increased mortality with succinylcholine in high-severity TBI (OR 4.1; 95% CI 1.2-14.1) 1
  • Succinylcholine causes transient increases in intracranial pressure 1
  • Rocuronium avoids this risk and can be rapidly reversed with sugammadex if neurologic examination is needed 3

Intubation Success Rates

Both agents provide comparable first-pass success rates:

• Rocuronium 1.2 mg/kg: 74.6% first-pass success 1
• Succinylcholine 1 mg/kg: 79.4% first-pass success 1
• The difference of -4.8% was inconclusive for noninferiority 1

When rocuronium is dosed >0.9 mg/kg, no superiority of succinylcholine was found 4

Critical Contraindications to Succinylcholine

Avoid succinylcholine in:

• Hyperkalemia risk: burns >24 hours old, crush injuries, prolonged immobilization, denervating conditions
• Severe TBI with elevated intracranial pressure
• Known malignant hyperthermia history
• Neuromuscular disorders

Important Caveats

Post-Intubation Awareness Risk:

• Rocuronium's longer duration (30-60 minutes) may mask inadequate sedation 1
• 7 of 10 patients reporting post-intubation awareness had received longer-acting paralytics 1
• Mitigation: Ensure immediate post-intubation analgosedation is administered, particularly with rocuronium
• Clinical pharmacist involvement reduces awareness risk 1

Practice Trends:

• Rocuronium use has increased dramatically from 33.9% (2015) to 61.9% (2022) in community EDs 5
• Emergency physicians historically prefer succinylcholine more than anesthesiologists (55.6% vs 27.7%) 6
• Rocuronium is more commonly chosen in patients with pre-intubation hypoxemia and when using video laryngoscopy 7

Practical Algorithm

Step 1: Assess for succinylcholine contraindications

• If present → Use rocuronium 1.2 mg/kg

Step 2: Identify if severe TBI present

• If yes → Use rocuronium 1.2 mg/kg (lower mortality risk)

Step 3: For general trauma without contraindications

• Succinylcholine 1 mg/kg may offer slight mortality advantage 2
• Rocuronium 1.2 mg/kg is acceptable alternative

Step 4: Regardless of agent chosen

• Prepare immediate post-intubation sedation/analgesia
• Have sugammadex available if rocuronium used and reversal needed