A Randomized Placebo-Controlled Trial Investigating the Effects of Melatonin on Hemodynamic Changes during Intubation and Laryngoscopy

Abstract

Background: Laryngoscopy and endotracheal intubation are critical components of general anesthesia during surgical procedures. While most patients' hemodynamic responses to the stress caused by these procedures are normal, those with cardiac problems are more likely to experience hemodynamic instability during anesthetic induction and endotracheal intubation. This frequently presents as increased blood pressure and heart rate. Melatonin has been offered as a way to reduce these hemodynamic reactions. Aims: This study attempted to explore changes in blood pressure and heart rate during endotracheal intubation in patients undergoing general anesthesia, comparing two groups: one given sublingual melatonin and the other given a sublingual placebo. Methods: Eighty patients, designated as American Society of Anesthesiologists grade I or II and aged 20 to 45 years old, scheduled for elective surgical procedures under general anesthesia, were divided evenly into two groups: Group C (control) and Group M (melatonin). They got either an oral placebo or sublingual melatonin tablets (6 mg) 120 minutes before surgery. Hemodynamic parameters were measured before surgery, during laryngoscopy and endotracheal intubation, and at 1, 3, 5, 10, and 15 minutes afterward. Results: During laryngoscopy and intubation, the control group experienced a significant increase in heart rate and blood pressure, which persisted for up to 10 minutes after intubation. In contrast, the melatonin group experienced a non-significant increase in heart rate during laryngoscopy and intubation, which returned to normal within 1 minute of intubation. Conclusion: Melatonin is effective at reducing the cardiovascular reactions to endotracheal intubation and laryngoscopy.