Rachianesthésie à la bupivacaïne sans glucose chez le vieillard : influence de la concentration et du volume sur le profil hémodynamique

Abstract

This study aimed to compare the haemodynamic effects of two different glucose-free bupivacaine solutions is thirty patients aged more than 70 years (mean age 82 years) undergoing hip surgery under spinal anaesthesia. They were randomly assigned to two groups, group A to receive 2.5 ml of a 0.5 % bupivacaine solution, and group B 10 ml of a 0.125 % solution in normal saline. All the patients were therefore given the same dose of bupivacaine, 12.5 mg. Lorazepam (1 mg orally) was administered to all for premedication two hours beforehand. Those patients taking antihypertensive agents were given their last dose on the eve of surgery. Lactated Ringer's solution (500 ml) was infused to all before the spinal puncture. Systolic (Pa sys), mean and diastolic arterial pressures, and heart rate, were recorded every minute before volume loading, and for 30 minutes after the start of the spinal anaesthesia. Ephedrine (3 mg every two minutes if required) was given whenever Pa sys decreased by more than 30 % of the pre-induction value. The upper level of sensory blockade was assessed by the pin-prick test, and the quality of motor blockade with the Bromage scale. The cephalad spread of the solutions was similar, as well as the haemodynamic profile in cach group. The total dose of ephedrine required in each group was not significantly different. It may therefore be concluded that, in the elderly, the upper level of, and the haemodynamic changes due to, spinal anaesthesia do not depend on the concentration or the volume of glucose-free bupivacaine solution.