Anaesthesia for cardioversion--clinical experiences with propofol and thiopentone

A 1-year population of anaesthesias for cardioversion of supraventricular tachyarrhythmias was studied. Propofol and thiopentone were used alternately for every other procedure, and the anaesthetic-, and monitoring procedures were prospectively standardized. Twenty-one thiopentone- and 23 propofol-anaesthetized patients, who had been subjected to elective cardioversions of atrial fibrillation were compared, particularly regarding possible differences in the energy requirements for cardioversion and in the time intervals to initial awakening. There were no significant differences between the two drugs in the maximum systolic blood pressure drop, in the total mean energy requirements per kg bodyweight, or in the distribution of the number of patients over the various energy levels needed for restoration of sinus rhythm. Somewhat unexpectedly, however, the mean time interval to initial awakening was significantly longer in the propofol-anaesthetized group. Apart from this minor drawback, propofol proved to be as useful an anaesthetic agent as thiopentone for the cardioversion procedure, and may be considered as an alternative drug in selected cases.