Role of Melatonin in Attenuation of Haemodynamic Responses to Laryngoscopy and Intubation in General Anaesthesia

Abstract

Objective: The aim of the study was to study the effects of melatonin in attenuation of hemodynamic responses such as heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean blood pressure (MBP) to laryngoscopy and intubation (L&I) in general anesthesia. Methods: This was a prospective and observational study conducted in a tertiary care teaching hospital on 120 patients aged 20–45 years belonging to American Society of Anaesthesiologists Grade I, undergoing elective surgery under general anesthesia. Selected patients were allotted into Group A (control group) and Group B (patients who took tablet melatonin 6 mg, 120 min before induction) of 60 patients each. Hemodynamic parameters such as HR, systolic, diastolic, and MBPs were recorded before the administration of drug (baseline), 120 min after administration of study drug (just before induction), immediately after induction, at L&I, just after L&I and at 1, 3, 5, and 10 min thereafter. Results: The gender distribution and mean age of both groups were comparable. Both the groups were also comparable with respect to baseline values of HR, systolic, diastolic, and mean arterial pressure. The control group showed significant increases in HR, SBP, DBP, and mean arterial blood pressure after L&I and this increase persisted for the next 10 min. In the melatonin group, there was no significant increase in HR, systolic, diastolic, or MBP at any point of measurement after L&I. Conclusion: Pre-treatment with 6 mg oral melatonin 120 min before induction of anesthesia is effective for attenuating hemodynamic responses to L&I without significant side effects.