Vasovagal syncope and anaesthetic practice

Abstract

We surveyed anaesthetists working in North-West England and in North Wales concerning episodes of vasovagal syncope encountered in their practice. Eighty-eight anaesthetists described 109 such events occurring in either patients or their relatives and the estimated frequency of syncope was 1 in 5000 anaesthetic episodes. The patient syncopal episodes were triggered by venous cannulation in 16 instances and regional or local techniques in 20 instances. Thirty-three of the 53 patients were in the upright position when syncope occurred. Thirty-nine of the 56 relatives were male partners of female patients and four of these partners suffered some morbidity. The results of the survey are consistent with our current knowledge of the pathophysiology of vasovagal syncope, which is summarized, and also highlight the common anaesthetic scenarios where fainting is most likely to occur. Given this information anaesthetists will be in a better position to avoid such potentially harmful episodes in the future.