A study to evaluate the effect of oral melatonin on patient’s anxiety scores and the dose requirement of propofol by bispectral index guided induction of general anaesthesia

Preoperative anxiety is a common occurrence in patients undergoing surgery, and it can lead to a range of negative effects, including an increased requirement for anesthetic agents, hemodynamic instability, and delayed recovery. Melatonin has been shown to have an anxiolytic and hypnotic effect with fewer side effects. This study aimed to explore the potential of oral melatonin to reduce preoperative anxiety levels and the dose requirement of propofol for the induction of general anesthesia. The study included 150 patients who were equally divided into two groups: Group M and Group C. Group M received oral melatonin 6mg and vitamin B complex tablets, while Group C received a sip of water and vitamin B complex tablets 90 minutes before the surgery. Anxiety levels were measured using the VAS score preoperatively and 90 minutes after drug administration. Propofol was given until the BIS value was sustained for 1 min at 48\(\pm\), and the total dose was measured in both groups. Postoperative pain was assessed using the VAS score just after extubation and every hour for the next 4 hours, with Inj. Diclofenac given if the score was \(\geq\)4. The time of first rescue analgesia was noted. Results showed that Group M had a significantly reduced VAS score and required a lower dose of propofol for induction compared to Group C (p\(\leq\)0.0001). The time of first rescue analgesia was also prolonged in Group M compared to Group C (p\(\leq\)0.0001). Therefore, oral melatonin is an effective premedicant that reduces preoperative anxiety, the required induction dose of propofol, and provides postoperative analgesia.