What are the options for intubation in a post-cardiac arrest patient with return of spontaneous circulation (ROSC) without using a muscle relaxant, such as rocuronium?

Intubation Without Muscle Relaxants in Post-ROSC Patients

Yes, intubation without muscle relaxants is a viable option in post-cardiac arrest patients with ROSC, particularly when adequate sedation alone can facilitate intubation, though this approach requires careful patient assessment and may necessitate short-term neuromuscular blockade only if sedation fails to achieve safe airway control.

Clinical Context and Decision Framework

The post-ROSC patient often presents with altered consciousness that may facilitate intubation without paralysis. The American Heart Association guidelines emphasize securing the airway with endotracheal intubation and using waveform capnography for confirmation, but do not mandate muscle relaxant use in all cases 1.

When Intubation Without Muscle Relaxants Is Appropriate

Deeply unconscious or comatose patients who cannot follow verbal commands after ROSC may be intubated using sedation alone 2. The key is achieving adequate depth of sedation with short-acting agents while maintaining hemodynamic stability 2.

Recommended sedation approach:

• Start with low-dose opioid analgesia (such as fentanyl or remifentanil) as the foundation 2
• Add short-acting sedatives only if analgesia alone is insufficient—preferred agents include propofol, dexmedetomidine, or remifentanil 2
• Use titrated, light-to-moderate sedation to maintain patient comfort while avoiding deep sedation that delays neurological assessment 2

When Muscle Relaxants Should Be Considered

Short-term neuromuscular blockade is indicated when:

• Patient agitation is life-threatening and adequate sedation has failed 2
• Patient-ventilator dyssynchrony is compromising ventilation despite appropriate sedation 3, 2
• The patient requires controlled ventilation parameters that cannot be achieved with sedation alone 3

The American Heart Association recommends avoiding or minimizing neuromuscular blocking agents, using them only for short intervals when absolutely necessary 2.

Critical Safety Considerations

Hemodynamic instability risk: Post-cardiac arrest patients often have preload-dependent cardiovascular systems due to myocardial dysfunction 4, 5. Both sedation medications and positive pressure ventilation can decrease preload and precipitate cardiovascular decompensation or re-arrest 4. This risk exists whether or not muscle relaxants are used.

Mitigation strategies:

• Ensure adequate volume resuscitation before intubation 5
• Target mean arterial pressure ≥65 mmHg, preferably >80 mmHg 3, 5
• Have vasopressors immediately available 5
• Anticipate possible cardiac arrest during the intubation procedure 4

Ventilation Management Post-Intubation

Once the airway is secured (with or without muscle relaxants):

• Provide 1 breath every 6 seconds (10 breaths per minute) with continuous chest compressions if still in arrest 1
• After ROSC, use low tidal volume ventilation (6-8 mL/kg predicted body weight) 3
• Titrate inspired oxygen to achieve arterial oxygen saturation of 92-98% 6, 5
• Target PETCO₂ of 35-40 mmHg or PaCO₂ of 40-45 mmHg, avoiding hyperventilation 3, 6, 5
• Apply appropriate PEEP (4-8 cm H₂O) while avoiding excessive airway pressures 3

Common Pitfalls to Avoid

Oversedation can delay neurological prognostication, mask seizure activity, and prolong mechanical ventilation 2. Use the minimum sedation necessary to achieve safe intubation and ventilator synchrony.

Undersedation can lead to patient-ventilator dyssynchrony, agitation, and shivering during targeted temperature management 2. Monitor sedation depth using validated scales such as RASS 2.

Delayed intubation should never occur due to concerns about muscle relaxants—the airway must be secured promptly 4. The decision is whether to use sedation alone or add neuromuscular blockade, not whether to delay the procedure.

Alternative Muscle Relaxant Options If Needed

If muscle relaxation is required, rocuronium in large doses (≥1 mg/kg) provides rapid intubating conditions as an alternative to succinylcholine 7, 8. However, its longer duration of action means loss of spontaneous ventilation for an extended period 7, 8.