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Suxamethonium-induced porcine malignant hyperthermia
British Journal of Anaesthesia
|June 1, 1976
Summary
Suxamethonium (SCh) triggers malignant hyperthermia (MH) faster than halothane in susceptible swine. While metabolic and temperature changes were similar, SCh caused smaller increases in lactate, potassium, and catecholamines, suggesting distinct MH pathway involvement.
Area of Science:
- Anesthesiology and Pharmacology
- Comparative Physiology
- Biochemistry
Background:
- Malignant hyperthermia (MH) is a severe pharmacogenetic disorder of skeletal muscle.
- Halothane is a known trigger for MH, characterized by hypermetabolism and muscle rigidity.
- The response of MH-susceptible individuals to other anesthetic agents requires further elucidation.
Purpose of the Study:
- To compare the metabolic, hemodynamic, and neuroendocrine responses to suxamethonium (SCh) in normal and MH-susceptible swine.
- To contrast the MH triggering potential of SCh with that of halothane.
- To investigate the underlying mechanisms of SCh-induced MH related to calcium regulation.
Main Methods:
- Administered suxamethonium (SCh) to normal and MH-susceptible swine.
- Monitored metabolic parameters (aerobic metabolism, lactate, potassium, hydrogen ion).
- Measured hemodynamic and neuroendocrine (catecholamine) responses.
- Compared results with previously reported data for halothane.
Main Results:
- Suxamethonium induced a faster and more abrupt onset of malignant hyperthermia compared to halothane.
- Maximal changes in aerobic metabolism and body temperature were similar between SCh and halothane.
- SCh elicited smaller increases in lactate, potassium, hydrogen ion, and catecholamine concentrations than halothane.
Conclusions:
- Suxamethonium is a potent trigger for malignant hyperthermia in susceptible swine, with a rapid onset.
- The observed differences in biochemical responses suggest distinct mechanisms for SCh- and halothane-induced MH.
- Dysregulation of intracellular calcium handling, potentially affecting the calcium pump or storage, is implicated in SCh-induced MH.
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