Vasovagal syncope and anaesthetic practice

We surveyed anaesthetists working in North-West England and in North Wales concerning episodes of vasovagal syncope encountered in their practice. Eig hty-eight anaesthetists described 109 such events occurring in either patie nts or their relatives and the estimated frequency of syncope was 1 in 5000 anaesthetic episodes. The patient syncopal episodes were triggered by veno us cannulation in 16 instances and regional or local techniques in 20 insta nces. Thirty-three of the 53 patients were in the upright position when syn cope occurred. Thirty-nine of the 56 relatives were, mate partners of femal e patients and four of these partners suffered some morbidity. The results of the survey are consistent with our current knowledge of the pathophysiol ogy of vasovagal syncope, which is summarized, and also highlight the commo n anaesthetic scenarios where fainting is most likely to occur. Given this information anaesthetists will be in a better position to avoid such potent ially harmful episodes in the future.