A Case of Masseter Muscle Rigidity during Awake Intubation under Remifentanil Infusion

Abstract

Opioids are very useful for tracheal intubation, but they carry risks of glottic closure and muscle rigidity. In awake intubation, these complications can lead to serious or even fatal outcomes. We encountered a case of mild masseter muscle rigidity during awake intubation under remifentanil（0.1 μg/kg/min）. Muscle rigidity occurs in 2-8% of cases of remifentanil administration；high dosage and rapid injection of opioids are risk factors. In this case the dose was comparatively low, but muscle rigidity occurred. When using opioids for awake intubation, clinicians must bear in mind that muscle rigidity can occur before loss of consciousness.