Prolonged Apnoea with Succinylcholine during Electro-convulsive Therapy

Electro-convulsive therapy (ECT) is one of the important treatment modality for psychiatric patients, particularly in developing countries like India. The introduction of curare and subsequently succinylcholine chloride (Holmerg and Thesleff 1952) as an important adjunct in the administration of ECT, was a major advance in reducing the morbidity associated with ECT. The relative safety of succinylcholine, a depolarising neuromuscular blocking agent, in ECT, has been extensively investigated (Holmerg and Thesleff 1952, Pitts et al 1968). Side effects of succinylcholine (include bronchial secretion, bradycardia, bronchospasm, muscle pain and hyperkalaemia (Wylie and Churchill Davidson 1966). One rare serious complication of succinylcholine administration is prolonged apnoea due most often to an increased duration of action. This increased duration of action may result from decreased metabolism of succinylcholine as seen in genetic pseudocholinesterase deficiency syndrome (Lehmaun and Liddell 1969), exposure to or treatment with anticholinesterase agents (Pantuck 1966) or as a result of additive effects caused by other drugs having neuromuscu lar blocking side effects (Pittinger et al 1970). Shortly after clinical introduction of succinylcholine, reports appeared describing prolonged apnoea immediately following the drug's administration during surgical procedures (Argent et al 1955) or after ECT (Hurley and Munro 1952).