Rapid Sequence Induction

Learning objectives

After completing this chapter, you should be able to determine when RSI is appropriate; optimize oxygenation and hemodynamics; perform a team brief; select induction and neuromuscular-blocking agents based on maternal physiology and contraindications; use pregnancy-specific positioning and aspiration precautions; manage failed attempts and peri-intubation deterioration; confirm tube placement; and provide immediate postintubation analgesia, sedation, ventilation, and fetal reassessment.

Opening transport scenario

A 28-year-old patient at 32 weeks has severe asthma, exhaustion, and a rising EtCO₂ despite aggressive treatment. SpO₂ is 90% on noninvasive ventilation, BP is 98/60 mm Hg, and fetal heart rate has recurrent late decelerations. RSI may be lifesaving, but induction can remove sympathetic tone, spontaneous ventilation, and the remaining oxygen reserve. The team must optimize first and choose medications based on bronchospasm, borderline pressure, aspiration risk, and the possibility of a difficult airway.

1. Is RSI the correct airway strategy?

RSI combines a sedative-hypnotic induction agent with a rapidly acting neuromuscular blocker to facilitate tracheal intubation. It is appropriate when the airway must be secured and the benefits outweigh the risk of removing spontaneous breathing.

Common indications

• Failure to oxygenate or ventilate despite noninvasive support
• Loss of airway protection or declining mental status
• Severe fatigue, status asthmaticus, pulmonary edema, ARDS, or traumatic injury
• Need for controlled ventilation during refractory seizure or critical transport

Reasons to consider another approach

• Predicted difficult intubation plus difficult mask/SGA oxygenation
• Upper-airway obstruction that may worsen after paralysis
• Severe physiologic instability not yet optimized
• A cooperative patient suitable for awake intubation by an experienced team

2. Physiologic optimization before induction

RSI does not correct shock or inadequate preoxygenation. Prepare for peri-intubation cardiac arrest by correcting reversible problems before drugs whenever time allows.

• Position head-up/ramped with left uterine displacement.
• Maximize preoxygenation and recruit lung volume when appropriate.
• Obtain reliable IV/IO access and prepare a flush.
• Correct severe hypotension with mechanism-appropriate fluid, blood, or vasopressor support.
• Treat bronchospasm, tension pneumothorax, severe acidosis, hypoglycemia, and dysrhythmia.
• Prepare suction, Plan B oxygenation, and emergency airway rescue.
• Brief maternal, fetal, neonatal, and procedural roles.

3. Preoxygenation and aspiration preparation

Use head-up positioning and a tight mask. The SCCM RSI guideline suggests high-flow nasal oxygen when laryngoscopy may be challenging and noninvasive positive-pressure ventilation for severe hypoxemia. Medication-assisted preoxygenation may be considered when agitation prevents effective oxygen delivery.

• Continue effective NIV until the induction sequence begins.
• Use nasal oxygen during apnea when appropriate.
• Decompress a markedly distended stomach or existing gastric tube when benefit outweighs risk.
• Have suction on and within reach before medication administration.
• Use gentle pressure-limited mask ventilation if needed to prevent desaturation.

4. Induction agents

Always administer an induction agent when using neuromuscular blockade. Choose based on physiology, not habit. Common adult educational ranges are shown; follow local protocols and reduce dose when shock or profound frailty warrants.

The 2023 SCCM guideline found no clear mortality or hypotension advantage of etomidate over other induction agents and advises against routine corticosteroids solely to counter etomidate-related adrenal suppression.

5. Neuromuscular blockade

The SCCM guideline recommends an NMBA when a sedative-hypnotic is used for RSI and supports either rocuronium or succinylcholine when succinylcholine has no contraindication.

Pregnancy-related pharmacology does not justify one universal dose reduction. Use actual or adjusted weight according to protocol and agent, while accounting for obesity, shock, and expected duration.

6. RSI procedure and first attempt

1. Confirm the indication and backup plan.
2. Apply monitoring: ECG, SpO₂, BP cycling frequently, and waveform capnography ready.
3. Position and preoxygenate.
4. Verify suction, laryngoscope, tube, bougie, SGA, emergency airway kit, ventilator, and drugs using closed-loop readback.
5. Administer induction, then NMBA without avoidable delay.
6. Use cricoid pressure if part of local obstetric practice, but reduce/release it if it impairs ventilation or laryngoscopy.
7. Perform the best optimized first attempt; avoid repeated identical attempts.
8. Inflate cuff, ventilate, and confirm continuous waveform capnography.

Brief pressure-limited mask ventilation is reasonable when needed to prevent severe hypoxemia. The goal is oxygenation, not rigid adherence to an apneic technique.

7. Failed attempt and peri-intubation rescue

8. Postintubation care

• Begin analgesia and sedation immediately; rocuronium can outlast induction substantially.
• Use pregnancy-aware ventilation targets and avoid unnecessary hyperventilation.
• Reassess blood pressure, EtCO₂, oxygenation, airway pressure, breath sounds, tube depth, and cuff.
• Secure the tube and repeat confirmation after every move.
• Treat the underlying problem—bronchospasm, pulmonary edema, hemorrhage, sepsis, seizure, trauma, or toxicity.
• Reassess fetal status after maternal stabilization when appropriate.

9. Transport-specific RSI planning

Before departure, ensure adequate oxygen, battery, sedation, analgesia, paralytic-management plan, vasopressor, suction, manual ventilation, and rescue airway equipment for the mission plus delay. Decide which deterioration requires stopping the vehicle or diverting.

10. Evolving case study

Phase 1: Preparation

The patient remains on NIV in a ramped position. The team prepares ketamine because of severe bronchospasm and borderline pressure, rocuronium because prolonged paralysis is acceptable, and a norepinephrine infusion for peri-intubation hypotension.

Phase 2: Intubation

After a closed-loop drug check, video laryngoscopy and a bougie achieve first-pass placement. Waveform capnography is immediately present. Gentle ventilation prevents severe desaturation during the attempt.

Phase 3: After the tube

Analgesia and sedation begin before movement. Ventilator settings are adjusted to avoid air trapping, pressure is supported, and fetal late decelerations improve as maternal oxygenation and perfusion recover.

11. High-yield chapter summary

1. RSI is a physiologic resuscitation, not merely a medication sequence.
2. Optimize oxygenation, position, perfusion, and the failure plan before induction.
3. Use an induction agent whenever an NMBA is administered.
4. Choose ketamine, etomidate, or propofol based on maternal physiology and contraindications.
5. Succinylcholine and rocuronium are both acceptable when appropriately selected.
6. Pregnancy does not mandate one universal dose change.
7. Gentle mask ventilation is appropriate when needed to prevent hypoxemia.
8. Release cricoid pressure if it obstructs ventilation or rescue.
9. Waveform capnography is essential for confirmation.
10. Start postintubation analgesia and sedation immediately.

References

1. International Board of Specialty Certification. Maternal Fetal Transport Microcredential Candidate Handbook. Updated April 2026.
2. Society of Critical Care Medicine. Clinical Practice Guidelines for Rapid Sequence Intubation in the Critically Ill Adult Patient. 2023.
3. Obstetric Anaesthetists’ Association and Difficult Airway Society. Guidelines for the Management of Difficult and Failed Tracheal Intubation in Obstetrics.
4. American Society of Anesthesiologists. Practice Guidelines for Obstetric Anesthesia.
5. American Society of Anesthesiologists. Practice Guidelines for Management of the Difficult Airway. 2022.