Management of malignant hyperthermia: diagnosis and treatment

Abstract

Malignant hyperthermia is a potentially lethal inherited disorder characterized by disturbance of calcium homeostasis in skeletal muscle. Volatile anesthetics and/or the depolarizing muscle relaxant succinylcholine may induce this hypermetabolic muscular syndrome due to uncontrolled sarcoplasmic calcium release via functionally altered calcium release receptors, resulting in hypoxemia, hypercapnia, tachycardia, muscular rigidity, acidosis, hyperkalemia, and hyperthermia in susceptible individuals. Since the clinical presentation of malignant hyperthermia is highly variable, survival of affected patients depends largely on early recognition of the symptoms characteristic of malignant hyperthermia, and immediate action on the part of the attending anesthesiologist. Clinical symptoms of malignant hyperthermia, diagnostic criteria, and current therapeutic guidelines, as well as adequate management of anesthesia in patients susceptible to malignant hyperthermia, are discussed in this review.

A Case Report of Suspected Malignant Hyperthermia: How Will the Diagnosis Affect a Patient’s Insurability?

“…For example, GINA provisions did not apply to life insurance, disability, or long-term care insurance, there was no mandate to provide coverage for genetic services, GINA did not prohibit the use of genetic test information in health insurance reimbursement decisions, and once genetic information has manifested itself into an actual health condition, this condition would no longer be protected by GINA [6, 7]. More important to the discussion of our patient with suspected MH, genetic testing is highly specific, but the sensitivity can be only about 50% [8]. Therefore, a negative test cannot rule out MH susceptibility and we relied more on the clinical signs and supportive laboratory results.…”

Perioperative considerations in Walker–Warburg syndrome

“…Specifically, we monitored endtidal CO 2 partial pressure by continuous capnography, because excessive CO 2 production and marked hypercapnia is a sensitive early sign of MH 14. After placement of the rectal temperature probe, we also monitored the patient for hyperthermia.…”

PharmGKB summary

“…Epidemiological reports give the occurrence of MH as ranging anywhere from 1 in 5000 to 1 in 100,000 patients; however, since it only reveals itself in the presence of potent inhalational anesthetics and depolarizing muscle relaxants, the genetic prevalence of MH susceptibility (MHS) has been estimated to be as high as 1 in 2000 [24-27]. Given that the overall incidence of MH in the general population is low it is likely that sporadic causative mutations are rare, [28].…”

“…For example, in two retrospective studies of patients who had experienced MH episodes during anesthesia between 64.8 and 70% were male [26, 27, 29]. This could be due to bias for the types of surgeries requiring general anesthesia that may be more commonly performed in males.…”