Dexmedetomidine premedication with three different dosagesto attenuate the adverse hemodynamic responses of directlaryngoscopy and intubation: a comparative evaluation

Background Direct laryngoscopy and tracheal intubation predictably lead to transient and variable hemodynamic responses, which can be attenuated by α2-receptor agonists. The present study aimed to evaluate comparatively the three different dosages of dexmedetomidine (0.5, 0.8, and 1 (mu)g/kg) as premedication for the attenuation of these hemodynamic responses of direct laryngoscopy and intubation.Participants and methodsNinety adult consented patients of ASA grades I and II of either sex were randomized into three equal groups of 30 patients each in a double-blind manner. Dexmedetomidine in dosages of0.5 (mu)g/kg (group I), 0.8 (mu)g/kg (group II), and 1 (mu)g/kg (group III) was infused over 10 min aspremedication before propofol induction. The hemodynamic changes during infusion, after induction, and after laryngoscopy and intubation were recorded for statistical analysis. ResultsPatients with a comparable demographic profile showed a decrease in heart rate and blood pressure after dexmedetomidine infusion in a dose-dependent manner. Further decrease in heart rate and blood pressure after propofol induction showed a statistically significant (P 0.05) difference among groups. After laryngoscopy and intubation, the increase in heart rate and blood pressure was more evident in patients in whom low dosages of dexmedetomidine was infused with a statistically significant (P 0.05) difference among the groups. ConclusionPremedication with dexmedetomidine at a dosage of 1 (mu)g/kg attenuated the adversehemodynamic responses of laryngoscopy and intubation adequately.