Background: Laryngoscopy and tracheal intubation are known to provoke significant hemodynamic responses, characterized by increased heart rate and blood pressure, which can lead to adverse cardiac events in susceptible patients. This study compares the efficacy of oral melatonin and nebulized dexmedetomidine in attenuating these responses. Methods: This randomized, double-blind clinical trial included 60 patients undergoing elective surgeries requiring tracheal intubation. Patients were randomly assigned to receive either oral melatonin 5 mg or nebulized dexmedetomidine at a dose of 1 μg/kg. Primary outcomes measured were heart rate, systolic blood pressure, and diastolic blood pressure recorded at baseline, immediately after intubation, and at intervals up to 10 minutes post-intubation. Secondary outcomes included sedation levels assessed using the Ramsay Sedation Scale and the incidence of side effects such as nausea, headache, and hypotension. Results: Dexmedetomidine significantly reduced heart rate (P=0.04), systolic blood pressure (P=0.03), and diastolic blood pressure (P=0.05) compared to melatonin. Additionally, patients in the dexmedetomidine group achieved higher sedation levels with significant differences in Ramsay Sedation Scale scores (P=0.01 for score 3). There were no significant differences between the groups in terms of side effects. Conclusion: Nebulized dexmedetomidine is more effective than oral melatonin in attenuating the hemodynamic responses to laryngoscopy and tracheal intubation. Both agents were well-tolerated, but dexmedetomidine provided superior hemodynamic stability and deeper sedation. These findings support the use of nebulized dexmedetomidine as a preferable option in clinical settings where control of hemodynamic responses is critical.

Dexmedetomidine, Melatonin, Hemodynamic Response