The comparative efficacy of two different doses of fentanyl on hemodynamic response to laryngoscopy and tracheal intubation: Prospective, randomized control trail

Abstract

General anaesthesia with muscle relaxants using controlled ventilation involves laryngoscopy and tracheal intubation, which is associated with haemodynamic changes in the form of tachycardia and hypertension due to increased sympathoadrenal activity and are probably of no consequence in healthy individuals, but they may be hazardous to those with Myocardial Insufficiency and cerebrovascular disease. The objective of the present study was to compare the effect of two different doses of fentanyl with etomidate as an induction agent in attenuating haemodynamic stress response during laryngoscopy and endotracheal intubation. A randomised control trial was carried out on 60 adult patients (ASA I, II, III) undergoing elective surgery under general anaesthesia requiring endotracheal intubation. The patients were randomly allocated into two groups of 30 each i.e. group F2.5 and group F5 receiving fentanyl 2.5μg/kg and 5 μg/kg intravenously five minutes before intubation respectively. The pulse rate, systolic blood pressure, diastolic blood pressure, mean arterial pressure and rate pressure product were recorded at various time intervals up to ten minutes after intubation. The study showed that both the doses were equally effective in blunting the pulse rate response, but the 5μg /kg proved significantly effective in blunting the blood pressure response. The rate pressure product, a measure of cardiac O2 consumption was found to be significantly lower in fentanyl 5μg/kg compared to fentanyl 2.5μg/kg. Hence, we conclude that fentanyl in 5 mcg/kg dose is more effective in attenuating hemodynamic responses to intubation as compared to 2.5 mcg/kg.