In a case of laryngospasm during planned intubation where mask ventilation is impossible, should a provider use a neuromuscular blocker (such as succinylcholine) or wait for the induction medication (propofol) to wear off while trying to break the laryngospasm with additional propofol?

Management of Laryngospasm with Failed Mask Ventilation During Planned Intubation

Administer a neuromuscular blocker (succinylcholine) immediately rather than waiting for propofol to wear off or attempting to deepen anesthesia with additional propofol. This is a "can't intubate, can't ventilate" (CICV) emergency requiring immediate action to prevent hypoxic brain damage and death.

Rationale for Immediate Neuromuscular Blockade

The primary goal is preventing hypoxic brain damage and death, which takes absolute priority over theoretical concerns about prolonging apnea. 1

• Laryngospasm represents complete airway obstruction that prevents effective oxygenation, and waiting for propofol to wear off (approximately 529 seconds or ~9 minutes) will result in profound desaturation and potential death 1
• Propofol's effects on laryngeal muscles persist even at low concentrations (0.7 mg/mL), meaning awakening does not guarantee resolution of laryngospasm 1
• Neuromuscular blockade with succinylcholine reliably breaks laryngospasm by eliminating the muscular component of the obstruction 2, 3, 4

Why Not Additional Propofol

• Small doses of propofol (0.8 mg/kg) have been studied for laryngospasm relief but failed in 23% of cases, with those patients requiring intubation 3
• Deepening anesthesia with more propofol prolongs apnea time (potentially 270-487 seconds depending on dose) without guaranteeing laryngospasm resolution 1
• This approach wastes critical oxygenation time in a patient who is already unable to be ventilated 1

Immediate Action Algorithm

Step 1: Call for Help and Prepare for Surgical Airway

• Summon the most experienced airway operator and surgical team capable of emergency cricothyroidotomy 5
• Have cricothyroidotomy equipment immediately available 1

Step 2: Optimize Oxygenation Attempts

• Apply 100% oxygen with positive pressure ventilation 2, 3
• Reduce or release cricoid pressure if applied, as it can worsen airway obstruction 1
• Attempt jaw thrust and optimal head positioning 1

Step 3: Administer Succinylcholine Immediately

• Give succinylcholine 1 mg/kg IV (or 4 mg/kg IM if no IV access) 6, 4
• Succinylcholine effect duration is 7-12 minutes, which is shorter and more predictable than waiting for propofol to wear off 1
• The FDA label confirms succinylcholine should be available for emergency situations even before unconsciousness is fully induced 6

Step 4: Intubate Once Laryngospasm Breaks

• Proceed with intubation using optimal technique (video laryngoscopy if available, bougie ready) 1
• Limit to maximum 3 intubation attempts to avoid progressive airway trauma 5

Step 5: If Intubation Fails After Succinylcholine

• Attempt supraglottic airway (LMA) for temporary oxygenation 1
• If supraglottic airway fails, proceed immediately to cricothyroidotomy 1, 5

Critical Pitfalls to Avoid

Do not give repeated doses of propofol hoping to break the laryngospasm - this wastes time and deepens the crisis 1, 3

Do not wait for "spontaneous recovery" - laryngospasm during induction with propofol on board will not reliably resolve before critical hypoxemia occurs 1

Do not delay neuromuscular blockade due to concerns about "can't intubate, can't ventilate" - you are already in a CICV situation, and succinylcholine is the most reliable way to break laryngospasm and restore the ability to ventilate 1, 2, 4

Ensure adequate depth of anesthesia before attempting intubation after breaking the laryngospasm, as light anesthesia during recovery from succinylcholine increases risk of recurrent laryngospasm 1

Evidence Regarding Neuromuscular Blockade Safety

• Studies show that neuromuscular blockade does not necessarily increase apnea duration compared to propofol/opioid combinations, with some propofol/remifentanil combinations causing apnea lasting up to 12.8 minutes 1
• Muscle relaxants improve mask ventilation in most patients, with improvement documented in 19 patients and no worsening in a database of 698 difficult airway cases 1
• The ability to reverse rocuronium with sugammadex (if available) provides even faster recovery than succinylcholine (4.7 minutes vs 7-12 minutes), though succinylcholine remains the standard for acute laryngospasm 1, 7