Methods: Sixty patients aged 18-70 years old who underwent elective surgeries involving endotracheal intubation were randomised into three groups of equal size: i) control; ii) dexmedetomidine and iii) esmolol. Heart rate (HR) was measured at baseline (T0), after drug administration (T1), after induction of anaesthesia (T2), immediately after intubation (T3), and 3 min, 5 min and 10 min after intubation (T4, T5 and T6). BG was measured pre-operatively and 30 min post-intubation.
Results: Two-way repeated-measures analysis of variance showed significant time [within-group changes, F(3.2, 182.5) = 30.39, P < 0.001], treatment [between-group differences regardless of time, F(2, 57) = 50.24, P < 0.001] and interaction [between-group differences based on time, F(6.4, 182.5) = 37.65, P < 0.001] effects on HR. A significantly higher HR was observed in the control group compared to the dexmedetomidine and esmolol groups from T2 to T6. BG exhibited a significant time effect [F(1, 57) = 41.97, P < 0.001] with no significant treatment and interaction effects. All three groups showed a significant increase in BG from baseline.
Conclusion: Both dexmedetomidine and esmolol are equally effective in attenuating haemodynamic responses to laryngoscopy and intubation. However, both do not significantly modulate neuroendocrine stress.