Premium
Electrodiagnostic tests in the detection of malignant hyperthermia
Author(s) -
Eng Gloria D.,
Becker Matthew J.,
Muldoon Sheila M.
Publication year - 1984
Publication title -
muscle and nerve
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.025
H-Index - 145
eISSN - 1097-4598
pISSN - 0148-639X
DOI - 10.1002/mus.880070804
Subject(s) - malignant hyperthermia , halothane , anesthesia , contracture , medicine , motor unit , electromyography , compound muscle action potential , stimulation , barbiturate , inhalation , neuromuscular transmission , hyperthermia , caffeine , electrophysiology , surgery , anatomy , physical medicine and rehabilitation
Malignant hyperthermia (MH) can be a catastrophic and sometimes fatal reaction in certain susceptible individuals who are exposed to skeletal muscle relaxants such as succinylcholine and/or certain inhalation anesthetics such as halothane. In an attempt to develop a safe, simple in vivo test to identify the at‐risk patients, repetitive nerve stimulation (RNS) and electromyographic (EMG) studies were performed on 9 patients with MH, 15 patients suspected of having MH, and 9 control subjects. Serial recordings were made following injections of caffeine sodium benzoate, succinylcholine, and halothane at the test site. Measurements were done on the amplitude of the evoked compound motor action potentials (CMAP), on RNS, and on the number of negative peaks of motor unit potentials (MUP) on maximum EMG recruitment. The results showed the effects of the drugs on amplitudes of the CMAPs to be significant ( P < 0.001) in all three groups, but no significant differences were found among the groups ( P = 0.93). The negative peaks of MUP on EMG recording showed a significant difference upon introducing succinylcholine ( P < 0.001), and significant interaction effects of the treatment by the patient group. Preliminary comparisons of in vivo tests with in vitro contracture tests in nine patients showed good correlation.