Prevention of hypotension during induction of anesthesia with propofol and fentanyl: Comparison of preloading with crystalloid and intravenous ephedrine.

Abstract

In this study, we compared the effect of preloading with crystalloid and intravenous ephedrine against the hypotensive effects of propofol and fentanyl induction in ASA I-II patients scheduled for elective surgical procedures. 150 patients aged 18yrs to 60yrs were randomly allocated to one of the three groups of 50 patients each. Group-A (control) did not receive any study medication, group-B received Ringers lactate 20ml/kg over 10-15min and group-C received intravenous ephedrine 0.2mg/kg prior to induction of anesthesia. Anesthesia was induced with propofol 2.5mg/kg, fentanyl 1.5µg/kg and atracurim 0.5mg/kg. Heart rate and blood pressure were recorded before induction and then every min for 5min after induction of anesthesia. After the study period patients were intubated and anesthesia was continued as required. Hypotension was defined as a drop in systolic arterial pressure more than or equal to 20% of baseline. A significant decrease in systolic arterial pressure occurred in both the fluid loaded and the control group. Least decrease in systolic arterial pressure was seen in the ephedrine group. The incidence of hypotension was also lower in ephedrine group when compared with control group. We conclude that crystalloid preloading is not efficacious in preventing hypotension and ephedrine markedly attenuates, but does not fully abolish, the decrease in blood pressure caused by propofol and fentanyl induction.