[Diprivan and electroconvulsive therapy].

Anaesthesia for Electroconvulsive Therapy (ECT) is characterized by short repeat anaesthetic procedures, performed outside an operating theatre. The efficacy of ECT relies upon the occurrence of tonoclonic convulsions. Propofol seems to be the intravenous induction agent of choice for ECT. Its pharmacokinetic properties ensure a rapid and deep anaesthesia, of short duration, with a minimum of side effects, and a rapid recovery of good quality, suitable for short repetitive procedures. As low doses of propofol are used, a rapid injection is required to obtain the hypnotic effect. These low doses also have the advantage of not affecting the convulsion threshold and therefore the efficacy of ECT. Clear upper airways and prevention of tongue biting are ensured by inserting a Guedel airway after loss of consciousness and before the electric shock. Intravenous administration of 10-20 micrograms.kg-1 atropine prevents from bradycardia, related to initial vagal stimulation induced by the electric shock. Its action is potentiated by the anticholinergic effect of tricyclic antidepressants. Its use is also justified when suxamethonium is given to prevent patient's movements and possible ECT-related trauma. Only suxamethonium is suitable for these procedures because of its pharmacokinetic properties (rapid onset and short duration of action). The suggested doses for this indication range from 0.5 to 1 mg.kg-1. When contraindicated, suxamethonium may be replaced by a benzodiazepine, in order to achieve an acceptable degree of muscle relaxation. There may then be an effect on the convulsion threshold.