Masseter spasm and malignant hyperthermia: a retrospective review of a hospital-based pediatric otolaryngology practice

Int J Pediatr Otorhinolaryngol. 1992 Jan;23(1):45-50. doi: 10.1016/0165-5876(92)90078-4.


It has been claimed that the combination of halothane and succinylcholine, commonly used for anesthetic induction during short pediatric otolaryngologic procedures, is associated with a 1% incidence of masseter spasm (MS) which may be an early sign of malignant hyperthermia (MH). An 18-month retrospective chart review of all patients undergoing general anesthesia at the Children's Hospital of Pittsburgh (n = 14, 112) was conducted to assess the incidence of MS and its management. In addition, a separate subgroup of patients identified as being at risk for MH was also evaluated. In the otolaryngology service, the incidence of developing MS was 2 of 206 (1%) in children who were anesthetized with halothane and received succinylcholine, patients were identified in the MH high-risk group, and none developed MH. The findings affirmed the risks of using this combination of anesthetic and neuromuscular blocking agents during induction and the need for establishing management guidelines.

MeSH terms

  • Anesthesia, General / adverse effects*
  • Child
  • Family Health
  • Halothane / adverse effects*
  • Humans
  • Incidence
  • Malignant Hyperthermia / epidemiology*
  • Malignant Hyperthermia / genetics
  • Masseter Muscle / drug effects
  • Masseter Muscle / physiopathology*
  • Medical History Taking
  • Muscle Rigidity / epidemiology*
  • Retrospective Studies
  • Risk Factors
  • Spasm / epidemiology*
  • Succinylcholine / adverse effects*
  • Virginia / epidemiology


  • Succinylcholine
  • Halothane