Management of Ketamine‑Induced Laryngospasm When Paralytics Are Unavailable

Immediate Non‑Pharmacological Measures

• Call for assistance and continuously monitor vital signs and oxygen saturation while preparing airway equipment. 1
• Apply continuous positive‑pressure ventilation with 100 % oxygen via a reservoir mask and maintain upper‑airway patency with a jaw‑thrust. 1
• Avoid any unnecessary stimulation of the airway that could exacerbate the laryngospasm. 1

Mechanical Relief – Larson’s Maneuver

• Position the middle finger of each hand in the “laryngospasm notch” (the groove between the posterior mandibular border and the mastoid process) and apply firm pressure while simultaneously performing a jaw‑thrust; this maneuver frequently terminates the spasm. 1

Pharmacologic Management (Primary Agent: Propofol)

• Give propofol 1–2 mg kg⁻¹ intravenously for persistent laryngospasm or falling SpO₂. 1
• Small initial doses may resolve early‑stage spasm, but larger doses are required for severe or complete cord closure. 1
• Propofol deepens anesthesia and relaxes the vocal cords, providing airway relief without the need for neuromuscular blockade. 1

Alternative Vascular Access When IV Is Unavailable

• Establish intra‑osseous access to deliver propofol (or other emergency drugs) if peripheral IV access cannot be obtained promptly. 1

Adjunctive Medication for Secretions

• Keep atropine readily available to treat bradycardia and to reduce excessive salivation that may aggravate laryngospasm. 1

Escalation If Propofol Is Insufficient

• Administer additional propofol to deepen anaesthesia rather than accepting a sub‑therapeutic dose. 1
• Continue CPAP and positive‑pressure ventilation throughout; forceful bag‑mask ventilation may be necessary to overcome residual obstruction. 1
• If complete airway obstruction persists despite maximal pharmacologic and ventilatory measures, prepare for an emergency surgical airway (cricothyrotomy or tracheostomy). 2

Monitoring for Post‑Obstructive Complications

• Post‑obstructive pulmonary edema occurs in more than 50 % of laryngospasm episodes that involve forceful inspiratory effort against a closed airway. 2
• After resolution, watch for dyspnea, agitation, cough, pink frothy sputum, and a decline in oxygen saturation as early signs of pulmonary edema. 2

Critical Pitfalls to Avoid

• Do not wait for spontaneous resolution; the vocal cords rarely reopen before severe hypoxia or cardiac arrest develops. 1
• Do not use inadequate propofol doses; promptly increase the dose in severe cases. 1
• Recognize “silent inspiration” (no audible breath sounds) as a sign of complete obstruction requiring immediate aggressive intervention. 1

Evidence Quality and Guideline Authority

• The Difficult Airway Society (DAS) guidelines provide the highest‑quality evidence for managing laryngospasm without paralytics, endorsing a stepwise approach that prioritises propofol before considering neuromuscular blockade. The recommendations are based on robust clinical data and expert consensus. [1][3]