A comparative evaluation of efficacy of lignocaine and dexmedetomidine to attenuate hemodynamic and airway responses to endotracheal extubation in elective coronary artery bypass graft surgery: a prospective randomized double-blind clinical study

Background: Extubation is more stressful than intubation because it leads to unpredictable hemodynamic and airway responses. Therefore, in this study, we compared the efficacy of dexmedetomidine and lignocaine in attenuating hemodynamic and airway responses during extubation in patients undergoing on-pump coronary artery bypass graft (CABG) surgeries.Methods: Seventy patients classified as American Society of Anesthesiologists physical status III and IV, aged 18–65 years and of either gender, were scheduled for elective on-pump CABG surgery under general anesthesia. These patients were designated for extubation in the cardiac postoperative recovery room. They were randomly assigned to one of two groups: Dexmedetomidine Group (Group D, n = 35) received an intravenous (IV) bolus of dexmedetomidine at a dose of 0.5 µg/kg, while Lignocaine Group (Group L, n = 35) received an IV bolus of lignocaine at a dose of 1.5 mg/kg, administered 5 min before extubation over a period of 60 s. Heart rate (HR) and mean arterial pressure were measured immediately before administration (A0), at 1, 3, and 5 min post-administration of the study drug (A1, A3, and A5, respectively), at extubation (E), and at 1, 3, 5, 10, 15, and 20 min following extubation (E1, E3, E5, E10, E15, and E20, respectively). The quality of extubation was assessed using a four-point scale. Statistical analysis was performed using the chi-squared test and a repeated-measures analysis of variance with Bonferroni correction.Results: The mean HR in Group D significantly decreased from E1 to E20 when compared with A0 (P < 0.05) and from E5 to E20 when compared with A1 (P < 0.05). By contrast, Group L showed significant variations in HR, including both increases and decreases, at various time intervals. The quality of extubation was found to be superior in Group D compared with Group L (P = 0.0003).Conclusions: A single dose of dexmedetomidine (0.5 µg/kg) given 5 min prior to extubation significantly reduced post-extubation HR and improved extubation quality compared with lignocaine (1.5 mg/kg) in patients undergoing on-pump CABG surgeries.