Malignant hyperthermia in a 6-month-old infant

Abstract

Malignant hyperthermia (MH) is a rare hypermetabolic disorder of skeletal muscles that manifests as a life-threatening crisis in susceptible individuals, after exposure to triggering agents, most commonly halothane and succinylcholine. MH presents with multiple nonspecific signs and laboratory findings such as tachycardia, hyperthermia, hypercarbia, acidosis, and muscle rigidity. Caffeine halothane contracture test is not available at most centers in India. Larach et al. have described a clinical grading scale for determining the MH raw score based on clinical findings and biochemical tests. The high degree of suspicion, early recognition and aggressive treatment should commence immediately. It is imperative to avoid triggering agents, such as volatile anesthetics and succinylcholine, and promote the use of total intravenous anesthesia in MH susceptible patients. We report a case of 6-month-old child undergoing laparotomy under general anesthesia, who presented with signs and symptoms of MH, had MH rank 5 and raw score 36.

Malignant Hyperthermia in a Child After Magnetic Resonance Imaging: A Case Report

“…The incidence of MH episodes during anesthesia is between 1:10,000 and 1:250,000 and, specifically in pediatric patients, 1:15,000. 1,4 Although MH may be triggered after a first exposure to anesthesia with known agents, on average, these patients require three exposures to such anesthetics before it is triggered. Male patients are most affected at a 2:1 ratio.…”

“…This begins after exposure to some of the anesthetic drugs already mentioned. 1,2,4,9 Tachycardia and tachypnea also occur in conjunction with these manifestations. In the absence of an appropriate and prompt medical intervention, the following may occur: rhabdomyolysis -with a risk of myoglobinuria -kidney damage, hyperkalemia, cardiac arrhythmias, and death.…”

“…In the absence of an appropriate and prompt medical intervention, the following may occur: rhabdomyolysis -with a risk of myoglobinuria -kidney damage, hyperkalemia, cardiac arrhythmias, and death. 1,3,4,10 The clinical manifestations that were present in the reported patient and which are part of the diagnostic criteria for MH are: generalized and masseter muscle stiffness, tachycardia, tachypnea, and hyperthermia (Tables 1 and 2). The laboratory tests of the patient (Table 3) did not show the classic metabolic acidosis or hypercapnia usually present in MH.…”

“…Auxiliary treatments should be instituted immediately after the administration of dantrolene, such as rapid temperature cooling with infusion of 15 mL/kg cold saline, 100% oxygen delivery with mild hyperventilation (when on mechanical ventilation), end-tidal carbon dioxide concentration (ET CO2 ) through capnograph and acidosis control. 3,4,8 The patient should be referred to the PICU for monitoring and treatment of possible complications such as cardiac arrhythmias due to hyperkalemia and acute renal injury due to myoglobinuria. 3,10 It is worth noting that the importance of different diagnoses, considering that MH can be confused with febrile seizures, especially in children in whom such seizures are very common until the age of five.…”

“…Other diseases with hypercatabolism should be ruled out, such as thyrotoxicosis, pheochromocytoma, sepsis, pyrogenic shock and some drugs, especially those that cause extrapyramidal symptoms. 1,4,9 There are also reports that susceptibility to MH increases in patients with certain congenital myopathies due to their association with mutation in the RYR1 gene. Medical professionals' prior knowledge of this information is essential in order to optimize the clinical care of these patients when they need surgery, as proposed by Bamaga et al 1,3,11 In order to assist health professionals and victims' families, a service for MH was created in Brazil in 1991 called Hotline (+ 55-11-55759873).…”