Prevention of post spinal hypotension; comparison between preloading with and without intramuscular ephedrine in elderly patients undergoing inguinal hernia surgery

ABSTRACT

Objective of the study is to evaluate the efficacy of intramuscular ephedrine along with preloading in prevention of post spinal hypotension in elderly patients undergoing inguinal hernia surgery. This is a quasi experimental study. The study was conducted at the department of Anaesthesia and Intensive Care Combined Military Hospital, Peshawar over a period of one year. In a double-blind, randomized study, 80 elderly patients undergoing inguinal hernia surgery under spinal anaesthesia divided into two equal groups of A and B. Forty patients received i/m inj of ephedrine 45mg deep in the paravertebral muscles immediately after injection of bupivacaine, and 40 received an equal volume of saline. Patients in both groups were given the same volumes of fluid before anaesthesia. The incidence of hypotension [Systolic arterial pressure <90mmHg or <80% of baseline] were recorded. and incidence of fall in the heart rate was recorded. Systolic arterial pressure during the first 60 min after anaesthesia remained significantly more stable in the ephedrine-treated group, and there was also a significantly smaller number of patients in this group who had decreases in pressure of more than 30% of pre-block levels and fewer required rescue i.v. Ephedrine. An increase in heart rate or systolic pressure of > 20% from baseline was found in two patients in the ephedrine group and in one patient in the placebo group. We conclude that ephedrine 45mg administered in the paravertebral muscles immediately after plain bupivacaine spinal anaesthesia is a simple and effective means of reducing the incidence of hypotensive episodes in the elderly patient