COMPARISON OF CATECHOLAMINE AND PRESSOR EFFECTS IN PERIBULBAR AND RETROBULBAR ANESTHESIA IN CATARACT-SURGERY

Peribulbar anaesthesia is now established as an alternative to retrobu lbar anaesthesia for cataract surgery, However, the larger volume of a naesthetic solution in the extraconal orbit with the peribulbar techni que might carry a higher risk of systemic side-effects. To assess this risk we carried out a prospective randomised comparison of plasma cat echolamine and presser effects between the two methods of anaesthesia in 40 patients, Plasma adrenaline and noradrenaline, heart rate, blood pressure, pain and anxiety were documented before and after local ana esthesia and during surgery, There were no statistically significant d ifferences between the responses of the two groups, Both groups demons trated a statistically significant rise in plasma adrenaline and heart rate. However, this change was minimal compared with the effects repo rted after severe stress or general anaesthesia, emphasising the impor tance of allaying patient anxiety during local anaesthesia, We have th erefore shown that the larger volume of extraconal orbital anaesthetic solution with the peribulbar technique produces no greater risk of sy stemic presser effects.