[Propofol-induced trismus, causing an unanticipated difficult intubation due to masseter spasm]

Area of Science:

• Anesthesiology
• Pharmacology

Background:

• Bilateral masseter spasm (BMS) is a rare complication during anesthesia induction.
• Understanding triggers and management is crucial for patient safety.

Observation:

• A 54-year-old male experienced two episodes of BMS within one month.
• Spasms occurred during induction of anesthesia with remifentanil and propofol.
• BMS led to difficult intubation and necessitated termination of general anesthesia on the first occasion.

Findings:

• Propofol infusion was identified as a potential trigger for BMS in this patient.
• The second event occurred despite planning an awake fiberoptic intubation, with propofol administration again leading to BMS.
• This adverse event associated with propofol has been reported to regulatory authorities.

Implications:

• Highlights the importance of recognizing propofol as a potential trigger for BMS.
• Suggests a need for careful consideration of anesthetic agents in patients with a history of masseter spasm.
• Emphasizes the critical role of prompt recognition and alternative airway management strategies in preventing complications.