Attenuation of Cardiovascular response by ß-blocker esmolol during laryngoscopy and intubation

Abstract

Cardiovascular responses to laryngoscopy and intubation have long been recognized and various efforts have been made to attenuate this response. The aim of this study was to evaluate the efficacy and safety of ß-blocker esmolol in attenuating cardiovascular response to laryngoscopy and tracheal intubation in the Ghanaian population. After obtaining institutional ethical approval, 80 patients aged 18 to 65 years from either sex and classified as American Society of Anaesthesiologists (ASA) physical status I (normal healthy patients) or II (Patients with mild systemic disease) undergoing elective surgery under general anaesthesia were selected for the study. Participants were randomly allocated into two groups comprising 40 subjects each. Group I received esmolol 2 mg kg^-1 I.V. bolus and group II (control) received a placebo 2 minutes prior to laryngoscopy. Changes in heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and rate pressure product (RPP) were measured before induction as baseline, and at minute 1, 3 and 5 minutes respectively after tracheal intubation while they were also observed for any complications. There was a significant attenuation in HR, SBP, DBP, MAP and RPP in the experimental group as compared to the control group (P < 0.05) at 1 minute with onward decreases at 3 and 5 minutes respectively after intubation. However attenuation to baseline values at 5 minutes after intubation in the experimental group was significantly higher than that in the control group. Percentage changes in haemodynamic variables in experimental group versus control group at 5 minutes are as follows: HR = -2.90% vs 10.22%; SBP = 0.96% vs 6.21%; DBP = -3.54% vs 4.06%; MAP = -1.56% vs 4.94%; RPP = -1.86% vs 17.25%. Prophylactic therapy with esmolol was found to be safe and effective in attenuating cardiovascular responses to laryngoscopy and tracheal intuba-tion among the Ghanaian population.