An evaluation of the effect of methohexitone and propanidid on blood pressure, pulse rate and cardiac arrhythmia during electroconvulsive therapy.

The effects of methohexitone and propanidid on the cardiovascular system of patients undergoing electroconvulsive therapy were evaluated on thirty-five patients. The anaesthetic and electroconvulsive therapy practice included intubation as a routine and pulmonary ventilation with 100 per cent oxygen between the administration of the shock and the onset of spontaneous respiration. The electrocardiogram was monitored continuously and the blood pressure and pulse rate were recorded at seven points in time during the procedure. In the evaluation only the first two treatment occasions were taken into consideration, methohexitone being used on one and propanidid on the other, the order for any given patient being determined at random. The effect of the order of the drugs was allowed for in the calculation of the results. Compared with propanidid, methohexitone was associated with higher systolic and diastolic blood pressures during the earlier stages and with lower pressures during the later stages. The higher blood pressures were in general associated with lower pulse rates and the lower pressures with slightly higher pulse rates. The return of spontaneous respiration was slower when propanidid rather than methohexitone was used. There was no reason to suspect a difference in the incidence of cardiac arrhythmia produced by the drugs.