Efficacy of fentanyl and esmolol in the prevention of haemodynamic response to laryngoscopy and endotracheal intubation.

OBJECTIVE: To compare the effectiveness of single bolus dose of esmolol or fentanyl in attenuating the haemodynamic responses during laryngoscopy and endotracheal intubation. DESIGN: Randomized, placebo controlled, double blind study. PLACE AND DURATION OF STUDY: Department of Anaesthesia and Surgical Intensive Care Unit, Civil Hospital, Karachi, from December 1998 to November 1999. PATIENTS AND METHODS: Sixty adult ASA-I and ASA-II patients undergoing elective surgery were included in the study. The patients were randomly divided into three groups i.e., A, B and C. Heart rate, systolic, diastolic and mean blood pressures were recorded as 0= baseline and after administration of study drug, laryngoscopy and endotracheal intubation and 10 minutes thereafter. Study agent was injected 30 seconds before the induction of anaesthesia. Group 'A' (control) received 10 ml saline, group 'B' and group 'C' received fentanyl 2 mg/kg and esmolol 2 mg/kg respectively diluted to make a total volume of 10 ml in normal saline. RESULTS: Readings of heart rate, systolic, diastolic and mean arterial pressures were compared with baseline and among each group. The rise in heart rate was minimal in esmolol group and was statistically significant. Following intubation, blood pressure was increased in all groups but was least in group C. CONCLUSION: Bolus injection of fentanyl 2 mg/kg 2 minutes prior to laryngoscopy and intubation failed to protect against elevation of both the heart rate and systolic blood pressure, whereas esmolol at 2 mg/kg provided consistent and reliable protection against the increase of heart rate but not arterial blood pressure.