Does Electroconvulsive therapy aggravate the rise in potassium and creatine kinase following suxamethonium administration

Background: Potassium and creatine kinase levels increase after the administration of suxamethonium. This rise may be exaggerated by the combination of suxamethonium fasciculation and the modified tonic/clonic convulsion induced by electroconvulsive therapy. This study compared the magnitude of increase in potassium and creatine kinase levels after electroconvulsive therapy and surgery using suxamethonium. Methods: A total of 40 patients were studied; electroconvulsive therapy (ECT), n=20 and surgery (Control), n=20. Intravenous sodium thiopentone (5mg/kg) and suxamethonium (1.5mg/kg) were administered. The changes in potassium and creatine kinase levels were assessed at presuxamethonium, 1 and 3 minutes after fasciculation in Control group and ECTinduced seizure activity in the ECT group. Our hypothesis was that a significant increase occurs in the mean potassium and creatine kinase levels after suxamethonium administration during electroconvulsive therapy. Results: Both groups exhibited a rise in potassium concentration after administration of suxamethonium. The mean increase was significantly higher in the ECT group than in the Control group; at 1 minute; ECT (0.71 ±SEM 0.24) versus control (0.28 ±SEM 0.19) mmol/L, p =0.003, and at 3 minutes; ECT (0.35 ±SEM 0.23) versus control (0.20 ±SEM 0.15), p =0.044. The mean increase in the creatine kinase concentration was significantly higher in the ECT group (34.11 ±SEM 10.76) than in the Control group (19.71 ±SEM 6.32) IU/L, p = 0.023, at 3 minutes. Conclusion: The creatine and potassium concentrations following suxamethonium administration were significantly higher in the electroconvulsive therapy group than in the control group. Keywords: ECT, surgery, creatine kinase, potassium