title: Increased requirement for minute ventilation and negative arterial to end-tidal carbon dioxide gradient may indicate malignant hyperthermia.
abstract: Characteristic signs of malignant hyperthermia (MH) include unexplained tachycardia, increased end-tidal carbon dioxide (Etco₂) concentration, metabolic and respiratory acidosis, and an increase in body temperature above 38.8°C. We present the case of a patient with highly probable MH. In addition to sinus tachycardia and metabolic and respiratory acidosis, this patient also had a negative arterial to Etco₂ gradient and an increased requirement for minute ventilation to maintain a normal Etco₂ concentration, with signs of increased CO₂ production. Despite these signs of MH, the patient's rectal temperature monitoring equipment did not show an increase in temperature, although the temperature measured in the mouth was increased. This case illustrates the unreliability of measuring rectal temperature as a means of reflecting body temperature during MH and the usefulness of increased CO₂ production signs in helping to diagnose MH.
authors.affiliation: Department of Anesthesiology, Taipei Veterans General Hospital and National Yang-Ming University School of Medicine, Taipei, Taiwan, ROC.
authors.forename: Ho-Tien
authors.initials: HT
authors.lastname: Lin
authors.affiliation: Department of Anesthesiology, Taipei Veterans General Hospital and National Yang-Ming University School of Medicine, Taipei, Taiwan, ROC.
authors.forename: Shen-Chih
authors.initials: SC
authors.lastname: Wang
authors.affiliation: Department of Anesthesiology, University of Virginia Health System, Charlottesville, VA 22908-0710, USA.
authors.forename: Zhiyi
authors.initials: Z
authors.lastname: Zuo
authors.affiliation: Department of Anesthesiology, Taipei Veterans General Hospital and National Yang-Ming University School of Medicine, Taipei, Taiwan, ROC.
authors.forename: Mei-Yung
authors.initials: MY
authors.lastname: Tsou
authors.affiliation: Department of Anesthesiology, Taipei Veterans General Hospital and National Yang-Ming University School of Medicine, Taipei, Taiwan, ROC.
authors.forename: Kwok-Hon
authors.initials: KH
authors.lastname: Chan
authors.affiliation: Department of Anesthesiology, Taipei Veterans General Hospital and National Yang-Ming University School of Medicine, Taipei, Taiwan, ROC. Electronic address: hbyuan@vghtpe.gov.tw.
authors.forename: Hui-Bih
authors.initials: HB
authors.lastname: Yuan
mesh_terms: D000368:Aged; D001158:Arteries; D001831:Body Temperature; D019296:Capnography; D002245:Carbon Dioxide / Q000032:analysis* / Q000097:blood; D005260:Female; D006801:Humans; D008305:Malignant Hyperthermia / Q000175:diagnosis* / Q000503:physiopathology; D013990:Tidal Volume
chemical_list: D002245:Carbon Dioxide
keywords: blood gas analysis; body temperature; capnography; malignant hyperthermia; pulmonary ventilation