Attenuation of hemodynamic responses to endotracheal extubation: A prospective randomised controlled study between two different doses of Verapamil

Abstract

Tracheal extubation causes significant hemodynamic stimulation resulting in transient increase in blood pressure and heart rate. This randomized, controlled, double blind study was conducted to compare the attenuation of hemodynamic responses to tracheal extubation in 150 patients of ASA I and II, undergoing elective surgery by using either verapamil 0.05 mg/kg or 0.1mg/kg with control group receiving saline. On completion of surgery, anaesthetic agents were discontinued, residual muscle relaxation reversed. The study drug was administered using double blind technique and patient extubated 2 minutes later. Changes in heart rate (HR), systolic arterial pressure (SAP), mean arterial pressure (MAP) and rate pressure product (PRBP) were recorded during and after tracheal extubation. This study showed that both the doses of intravenous verapamil attenuated the increases in these variables. The inhibitory effect was greatest with verapamil 0.1 mg/ kg, while the alleviative effect of verapamil 0.05mg/ kg was inferior. These findings suggest that a bolus injection of verapamil 0.1 mg/kg given 2 min before tracheal extubation is a more effective prophylactic for attenuating the cardiovascular changes associated with extubation than 0.05mg/kg dose.