Efficacy of three different doses of esmolol to attenuate the response of hemodynamic stress to laryngoscopy and endotracheal intubation in general anaesthesia surgeries - a controlled randomized comparative study

INTRODUCTION: Laryngoscopy and endotracheal intubation are essential procedures in patients undergoing surgery under general anaesthesia. However, they are invariably associated with a hemodynamic stress response, characterised by cardiovascular alterations such as tachycardia, hypertension, and a range of cardiac arrhythmias. In vulnerable individuals, these responses may have serious consequences, including perioperative myocardial ischemia, acute heart failure, and cerebrovascular accidents. Consequently, the present study aims to evaluate the efficacy of three different doses of Esmolol in attenuating the hemodynamic stress response to laryngoscopy and endotracheal intubation. MATERIALS AND METHODS: A prospective, randomised, comparative study was conducted involving 54 patients, who were randomly assigned to three groups of 18 each using a computer generated randomization sequence: Group E1 received a single intravenous (IV) bolus dose of Esmolol 0.8 mg/kg, Group E2 received Esmolol 1 mg/kg IV, and Group E3 received Esmolol 1.5 mg/kg IV. The study drugs by administered as a bolus injection two minutes after Vecuronium bromide. The hemodynamic parameters, heart rate (HR) and mean arterial pressure (MAP), were recorded at baseline (on arrival in the operating room), and at 1, 3, and 5 minutes after laryngoscopy and intubation. Additionally, venous blood samples were collected to assess serum cortisol and blood glucose levels at baseline and 5 minutes post-intubation. RESULTS: At baseline, MAP, HR, serum cortisol, and blood glucose levels were similar between the groups (p>0.05). At 1 minute after intubation, MAP was lower in Group E3 (68.4 mmHg) compared to Groups E1 (98.11 mmHg) and E2 (97.48 mmHg) (p<0.001). HR was highest in Group E1 (89.17 bpm), followed by Group E2 (85.56 bpm), and lowest in Group E3 (79.22 bpm) (p=0.006). At 5 minutes after intubation, both serum cortisol and blood glucose levels differed significantly between groups (p<0.001). CONCLUSIONS: All three Esmolol doses effectively attenuated the hemodynamic stress response to laryngoscopy and intubation. However, the 1.5 mg/kg dose was most effective, showing the greatest reduction in heart rate and blood pressure. It also causes a metabolic stress response but with lesser increases in serum cortisol and blood glucose.