Malignant hyperpyrexia—the difficulty of diagnosis

Abstract

Are cuffs necessary?Your recent edition on the airway highlights some interesting problems. The problems of long term intubation, by any route, seem to be related to the use of inflatable cuffs. Are these cuffs really necessary?For many years now it has been customary to use plain tubes in paediatric anaesthesia and intensive care. This requires more careful selection of the tube to avoid too big a leak or too tight a fit. We have not encountered problems due to aspiration.Perhaps the time has come for a critical reappraisal of intubation in adult practice. The provision of a wider range of sizes in plain tubes, coupled with more careful selection, might help to reduce the incidence of tracheal trauma. Ireland KEVIN P. MOORE Malignant hyperpyrexia-the difficulty of diagnosisWe have recently encountered a case of rapid peroperative temperature rise associated with an irregular tachycardia and hypoxaemia, following induction of anaesthesia for emergency appendicectomy. Despite fanning and infusion of cold Hartmann's solution the temperature rose to 40,5"C, and was only controlled when therapy was instituted along the lines suggested by Clark & Ellis' for the management of malignant hyperpyrexia. The classic presentation of this syndrome is well documented and its diagnosis consequently relatively easy. However when the rapid temperature rise occurs in patients undergoing surgery for conditions in themselves associated with fever a considerable diagnostic problem is posed. We narrowed the differential down to an infective, drug induced, or malignant hyperpyrexic aetiology.At the time a bacteraemia was thought unlikely as the rise in temperature occurred prior to opening of the peritoneum and manipulation of the bowel, and rose more rapidly and to a higher level than is usually associated with acute appendicitis. Britt et al. ' report that fever secondary to infection usually subsides during anaesthesia since cessation of muscle activity and vasodilatation result in lowered heat production and accelerated heat loss. It was neverth$-less thought necessary to cover the patient with antibiotics. Following therapy the temperature returned to normal within 4 hours and thereafter the patient remained apyrexial. Had infection been the cause a more gradual return with intermittent spiking would have been expected. Three clear blood cultures at the time of maximum fever, and a white cell count of only 11,300 one day post-operatively indicated that no bacteraemia of any significance had occurred. The only drug used in the anaesthetic sequence causing fever was atropine. It is known to result in a rise of temperature, a decrease in sweating, and an increase in heart rate. However Goodman & Gilman3 state that atropine induced hyperthermia is rarely a problem in adults, and only occurs if large doses in excess of 5 mg are used in ambient temperatures greater than 27.5"C. None of these criteria were fulfilled in this case.Thus we were left with a diagnosis of malignant hyperpyrexia. The patient had demonstrated definitive signs...

Myoglobinuria, 1984

“…It is stated that rigidity is not seen in 20% of acceptable cases (Britt and Kalow, 1970) and even fever may be lacking (Bernardt and Horder, 1978). If a child develops masseter rigidity at the start of general anesthesia and then there is no fever because cooling measures are promptly instituted (Carballo, 1975;Caseby, 1975;Davis, 1977, Donlon et al, 1978Dodd et al, 1981;Inoue et al, 1977;Jago and Payne, 1977;Schmitt et al, 1975), was this an aborted attack of MH or some other kind of reaction to succinylocholine? It is clearthat fullblown attacks of MH may start with masseter spasm and there have been cases of masseter spasm alone or with myoglobinuria but no other manifestations of MH; not all of these patients have "positive" tests for MH-susceptibility (Flewellen and Nelson, 1982).…”