ROLE OF MELATONIN IN ATTENUATION OF HAEMODYNAMIC RESPONSES TO LARYNGOSCOPY AND INTUBATION IN GENERAL ANAESTHESIA

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