Comparison of Intravenous Versus Nebulized Dexmedetomidine for Laryngoscopy and Intubation-Induced Sympathoadrenal Stress Response Attenuation.

BACKGROUND: Nebulized dexmedetomidine has been used for procedural sedation and allaying separation anxiety in children. Literature regarding its use in the attenuation of laryngoscopy and intubation response via the nebulized route is scarce. We evaluated preoperative dexmedetomidine nebulization on the hemodynamic response arising from laryngoscopy/intubation, hemodynamics, analgesic consumption, and postoperative sore throat.

OBJECTIVES: The primary objective was to evaluate/compare the hemodynamic effects of preoperative intravenous and nebulized dexmedetomidine on laryngoscopy/intubation and compare the efficacy of the two routes in blunting the sympathoadrenal response. The secondary objective was to evaluate their effects on intraoperative analgesic consumption and incidence and sore throat postoperatively.

METHODS: 120 ASA I & II adult patients undergoing elective surgeries requiring tracheal intubation were randomized to receive intravenous dexmedetomidine (1 µg/kg over 10 minutes) and nebulized dexmedetomidine (1 µg/kg in 3 - 4 mL of 0.9% saline), 30 min before anesthesia induction. Heart rate and non-invasive blood pressure were monitored for 10 min following laryngoscopy and then throughout the surgery. Intraoperative analgesic consumption, postoperative sore throat, and recovery from anesthesia were assessed.

RESULTS: No significant hemodynamic difference was found between the two groups till three minutes. Then, the difference turned significant owing to a greater fall in the heart rate and mean arterial pressure in the intravenous group. Nebulized dexmedetomidine exhibited a lesser tendency of hypo/hypertension and brady/tachycardia, while hemodynamics was more stable. There was lesser sore throat and sedation in the nebulized group. Intraoperative analgesic and propofol consumption was comparable between the two groups.

CONCLUSIONS: Nebulized dexmedetomidine attenuated laryngoscopy and intubation response, although to a lesser extent than the intravenous group in equivalent doses. However, the nebulized route provided greater hemodynamic stability in the intraoperative period and lesser sedation/sore throat postoperatively without an increase in adverse effects. Nebulized dexmedetomidine may provide a more holistic and viable alternative in patients who poorly tolerate hypotension, bradycardia, and sedation.