Anesthesia, malignant hyperthermia

Halogenated hydrocarbon inhalation anesthetics may increase intracranial and CSF pressure. Cardiovascular effects include decreased myocardial contractility and stroke volume leading to lower arterial blood pressure. Malignant hyperthermia may occur with all inhalation anesthetics except nitrous oxide but has most commonly been seen with halothane. Especially halothane but probably also the other halogenated hydrocarbons have the potential for acute or chronic hepatic toxicity. Halothane has been almost completely replaced in modern anesthesia practice by newer agents. 

Porphyria is not the only disorder that may he inadvertently precipitated by the administration of a drug. Malignant hyperthermia is a serious, life-threatening complication of general anesthesia with halothane, methoxyflurane, and succinylcholine. It occurs in 1 in 20,000 people. Clinically, it is characterized hy high body temperature (41°C), muscle rigidity, and cardiovascular collapse. 

Malignant hyperthermia has been described in a 10-year-old boy who received thiopental and suxamethonium for induction of anesthesia, followed by desflurane for maintenance of anesthesia (15). 

Malignant hyperthermia is a possible complication of isoflurane anesthesia (20). 

A 28-year-old man, who developed malignant hyperthermia after anesthesia induced with isoflurane and maintained with sevoflurane, died 4 days later, despite cooling and intravenous dantrolene (49). 

In more than 3000 cases in Japan, there were two cases of malignant hyperthermia, one fatal (49). In this case isoflurane had been used early in anesthesia, and could have been at least in part responsible. There was some reason to consider that the patient, a 12-year-old girl, had a family propensity to malignant hyperthermia, as indicated by higher resting Pi/Pcr values. However, sevoflurane itself can trigger malignant hyperthermia in swine (54). 

Otsuka H, Komura Y, Mayumi T, Yamamura T, Kemmotsu O, Mukaida K. Malignant hyperthermia during sevoflurane anesthesia in a child with central core disease. Anesthesiology 1991 75(4) 699-701. 

Hoshino K, Yamashiro Y, Nitta K, Kawaguchi H, Fukui H, Ikeda M, Ooshima Y. A case of postoperative malignant hyperthermia after 15 hours induced anesthesia. Hiroshima J Anesth 1996 32 15-18. 

Baris S, Karakaya D, Guldogus F, Sarihasan B, Tekat A. A case of malignant hyperthermia during sevoflurane anesthesia. Turk J Med Sci 2001 31 171-3. 

Determine if the patient has any blood relatives who have had reactions to anesthesia such as malignant hyperthermia. 

Central core disease has five allelic variants of RyR-1 patients with central core disease are highly susceptible to malignant hyperthermia with the combination of an anesthetic and a depolarizing neuromuscular blocker. Patients with other muscle syndromes or dystonias also have an increased frequency of contracture and hyperthermia in the anesthesia setting. 

In anesthesia protocols that include succinylcholine, which one of the following is a premonitory sign of malignant hyperthermia ... 

Dantrolene is a muscle relaxant that is currently the only effective treatment for malignant hyperthermia, a rare and life-threatening disorder that can be triggered by general anesthesia in some patients. Dantrolene has been synthesized by a number of different routes starting from readily available furaldehyde and its derivatives. 

Body temperature Malignant hyperthermia occurred 3 hours after the start of an operation for esophageal resection in an 82-year-old man after anesthesia induced with propofol and suxamethonium and maintained with sevoflurane [6 ]. Masseter spasm was not a feature. End-tidal CO2 rose to 55 mmHg and body temperature exceeded 39.0°C. The patient responded promptly to dantrolene. Reports of malignant hyperthermia in patients over the age of 80 years are unusual. Both suxamethonium and sevofiur-ane are potent triggers. 

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