title: The severity of sevoflurane-induced malignant hyperthermia.
abstract: BACKGROUND
  Malignant hyperthermia (MH) is a potentially fatal complication of general anesthesia triggered by volatile anesthetics. In animal studies, sevoflurane has been reported to be a weak triggering agent. The aim of this study was to evaluate the clinical severity of sevoflurane-induced MH compared to isoflurane.
  
  
  METHODS
  From the Japanese MH database containing information for 520 MH cases since 1961, we analyzed 147 cases classified by the MH Clinical Grading Scale (CGS) as 'very likely' or 'almost certain', accumulated from 1990 to 2009. Sevoflurane without succinylcholine (S-SCh (-) group) was given to 48 cases, and isoflurane without succinylcholine (I-SCh (-) group) was given to 30. Variables studied were outcome, CGS score, CGS rank, the first MH sign, and time from induction to onset of MH (occurrence time). Clinical signs and maximum laboratory data from six processes of the CGS were also analyzed. Each of the Mann-Whitney U-test or the unpaired t-test was used for group comparisons.
  
  
  RESULTS
  Mortality was 8.3% in the S-SCh (-) group and 10.0% in the I-SCh (-) group (P = 0.803). The CGS scores were 53.4 (SD, 12.2) and 52.3 (11.7) (P = 0.691), respectively. The five processes of the CGS did not differ between groups. Median occurrence times were 72.5 minutes (range, 36.3-127.5) and 65.0 minutes (30.0-131.3), respectively (P = 0.890).
  
  
  CONCLUSIONS
  There were no clinically apparent differences between MH triggered by sevoflurane and isoflurane, and thus no evidence to support the postulate that sevoflurane is a weak or weaker MH triggering agent.
authors.affiliation: Department of Anesthesiology and Critical Care, Hiroshima University Hospital, Hiroshima, Japan. migitataka@hiroshima-u.ac.jp
authors.forename: T
authors.initials: T
authors.lastname: Migita
authors.forename: K
authors.initials: K
authors.lastname: Mukaida
authors.forename: M
authors.initials: M
authors.lastname: Kobayashi
authors.forename: H
authors.initials: H
authors.lastname: Hamada
authors.forename: M
authors.initials: M
authors.lastname: Kawamoto
mesh_terms: D000293:Adolescent; D000328:Adult; D000769:Anesthesia, Inhalation / Q000009:adverse effects; D018685:Anesthetics, Inhalation / Q000009:adverse effects*; D001831:Body Temperature; D002675:Child, Preschool; D003402:Creatine Kinase / Q000097:blood; D003620:Dantrolene / Q000627:therapeutic use; D016208:Databases, Factual; D005260:Female; D006801:Humans; D007530:Isoflurane / Q000009:adverse effects; D007564:Japan; D008297:Male; D008305:Malignant Hyperthermia / Q000188:drug therapy / Q000401:mortality / Q000503:physiopathology*; D008738:Methyl Ethers / Q000009:adverse effects*; D008875:Middle Aged; D009125:Muscle Relaxants, Central / Q000627:therapeutic use; D009127:Muscle Rigidity / Q000139:chemically induced / Q000503:physiopathology; D009211:Myoglobin / Q000378:metabolism; D009467:Neuromuscular Depolarizing Agents; D000077149:Sevoflurane; D013390:Succinylcholine; D013610:Tachycardia / Q000209:etiology; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D009125:Muscle Relaxants, Central; D009211:Myoglobin; D009467:Neuromuscular Depolarizing Agents; D000077149:Sevoflurane; D007530:Isoflurane; D003402:Creatine Kinase; D003620:Dantrolene; D013390:Succinylcholine