Differences in the Onset and Severity of Symptoms of Malignant Hyperthermia with Different Inhalational Anesthetics

Abstract

Malignant hyperthermia (MH) is an uncommon inherited disorder of skeletal muscle in which commonly used anesthetics can trigger sustained skeletal muscle hypermetabolism in patients who may have had no symptoms previously. The onset and severity of clinical symptoms of MH are variable. Non-clinical studies and case reports have identified differences in the onset and severity of symptoms with the commonly used volatile anesthetics. The purpose of this study was to identify if there is a significant difference in the onset and severity of signs and symptoms of malignant hyperthermia in those MH-susceptible patients who received the different volatile anesthetics. A comparative descriptive research design was used. A retrospective review of the database at the (USUHS) MH muscle biopsy diagnostic center was done. The data collected was used to determine if there was a difference in the onset and severity of signs and symptoms of MH episodes with halothane compared to MH episodes of four other volatile anesthetics. For each of these groups, the following variables were assessed: highest temperature, highest end-tidal carbon dioxide, time from beginning of anesthetic until onset of first MH symptom, time of onset of anesthesia until initial treatment for MH, and the incidence of masseter spasm. Based on results of this study, there was no significant difference among the groups. As much of the pediatric data was excluded, the results may have been skewed. Further studies examining these differences between volatile anesthetics would be extremely valuable in understanding the pathophysiology of malignant hyperthermia.