Effect of preoperative dexmedetomidine nebulization on the hemodynamic response to laryngoscopy and intubation: a randomized control trial.

BACKGROUND: Dexmedetomidine, an alpha-2 agonist, has been used for attenuation of hemodynamic response to laryngoscopy but not through the nebulized route. We evaluated the effects of preoperative dexmedetomidine nebulization on the hemodynamic response to laryngoscopy and intubation and examined the intraoperative anesthetic-analgesic requirements and recovery outcomes.

METHODS: Overall, 120 American Society of Anesthesiologists I & II adult patients (of either gender) undergoing elective surgeries and requiring tracheal intubation, were randomized to receive nebulized dexmedetomidine (1 µg/kg in 3-4 ml of 0.9% saline) or 0.9% saline (3-4 ml), 30 min before anesthesia induction. Heart rate (HR) and non-invasive systolic blood pressure (SBP) were monitored for 10 min following laryngoscopy.

RESULTS: After laryngoscopy, linear mixed effect modelling showed significantly lower trend of increase in HR in the dexmedetomidine group versus saline (P = 0.012); however, there was no difference in the SBP changes between the two groups (P = 0.904). Induction dose of propofol (P < 0.001), intraoperative fentanyl consumption (P = 0.007), and isoflurane requirements (P = 0.013) were significantly lower in the dexmedetomidine group. There was no difference in the 2 h incidence of postoperative nausea and vomiting (PONV) (P = 0.612) or sore-throat (P = 0.741).

CONCLUSIONS: Nebulized dexmedetomidine at 1 µg/kg attenuated the increase in HR but not SBP following laryngoscopy and reduced the intraoperative anesthetic and analgesic consumption. There was no effect on early PONV, sore-throat, or increase in incidence of adverse effects. Nebulized dexmedetomidine may represent a favorable alternative to the intravenous route in short duration surgeries.