Clinical experiences of malignant hyperthermia encountered by Thai anesthesiologists

Abstract

Objective : To survey the clinical memorable experiences, which were suggested to intraoperative malignant hyperthermia (MH) among Thai anesthesiologists.

Material and Method : Questionnaires for a national survey of dantrolene requirement were sent by the Royal College of Thai Anesthesiologists (RCAT) to all Thai anesthesiologists (855 members) in 2007. One hundred and two (11.93%) questionnaires were returned. There were 25 anesthesiologists (24.51%), who had experiences of suspected MH events. All of them were later included for an interview by phone. The questions consisted of which part of the region the hospital is located in, the number of MH events, clinical manifestations, problems in the diagnosis and management, the outcomes in terms of mortality and medico-legal aspect, and preventive strategy for MH.

Results : The most frequent clinical signs of MH were inappropriate sinus tachycardia (100%), masseter spasm (84%), rapid increase in body temperature (64%), and generalized muscular rigidity (44%). Only half of the suspected MH patients were monitored with capnogram. About one-third (32%) of the patients received dantrolene. Acidosis was corrected in nearly two-thirds (60%) of the suspected MH patients. The mortality rate of MH was 36%. One anesthesiologist (4%) encountered litigation problem from a fatal case. Family counseling was conducted in 84% of cases. Suggestions from anesthesiologists, who experienced MH were expansion and publicity of dantrolene-stored hospitals, and more education programs on MH.

Conclusion : Although MH is a rare condition, it induces high mortality which potentially brings in the litigation. Earlier detection and shorten the time until the initial dantrolene administration should be acquired.