Succinylcholine induced masseter muscle rigidity: an isolated event

Abstract

Masseter muscle rigidity (MMR) during general anesthesia is considered to be an early warning sign of possible
episode of malignant hyperthermia (MH). We report a case of 36 year old male patient, posted for surgical repair
of epigastric hernia, which developed MMR following a standard dose of intravenous succinylcholine during
induction of anesthesia. Suspecting MMR as an early indicator of malignant hyperthermia, all the precautions
were taken and after securing the airway with endotracheal intubation anesthesia was maintained with propofol
infusion, avoiding triggering factor like halogenated inhalational agents. Patient’s temperature, end tidal CO2,
heart rate and blood pressure remained within normal limits during intraoperative and postoperative period.
Patient was carefully monitored and investigated in postoperative period and a moderate rise in serum creatinine
phosphokinase level (401 U/L) was recorded at 24 hours. He recovered well and was discharged uneventfully.