TO OBSERVE EFFECTS OF MELATONIN PREMEDICATION ON HAEMODYNAMIC RESPONSES TO LARYNGOSCOPY AND INTUBATION

Abstract

Laryngoscopy using rigid metal blade produces noxious stimuli that causes stimulation of sensory receptors which in turn causes release of endogenous catecholamines, which in turn provokes hemodynamic changes called stress response. Due to its inhibitory action on CNS which causes sedation and anxiolysis as well as suppression of catecholamine release, we hypothesized that oral melatonin tablet 10 mg, administered orally about 120 minutes before the procedure should provide hemodynamic stability and blunt this response. The primary objective of the study was to observe magnitude and duration of changes in vital parameters before, during and after laryngoscopy and intubation, in a group of patients who were premedicated with 10 mg mouth dispersible tablet melatonin 120 min anesthesia. Continuous numeric data on pulse rate, blood pressure, SPO2 were analyzed as mean and standard deviation. Signicance of observation was derived by applying student's t-test. Non parametric data on complication of study drug was reported as number of patients exhibiting the complication and also as percentage. One group of 35 patients received 10 mg of oral melatonin as mouth dispersible tablet 120 minutes before conduct of anesthesia and other group did not received the study drug and acted as control group for comparison. Pre induction hemodynamic parameters after 120 minutes of oral melatonin administration were recorded and after induction of anesthesia and intubation hemodynamic parameters were recorded. In group of patients who received melatonin the magnitude of rise of heart rate, systolic, diastolic and mean arterial pressure was less returning to pre induction value within 3 minutes. .In control group patients we observed a statistically signicant rise in magnitude of heart rate and blood pressure that remained elevated till 10 minutes after laryngoscopy and intubation. The rate pressure product, an indicator of myocardial oxygen demand and consumption was signicantly higher in control group and lasted for longer time. While in melatonin treated patients insignicant rise of RPP occurred. The clinical observations made in the present study allow us to conclude that oral melatonin administered 120 minutes before induction of anesthesia effectively controlled the stress response to laryngoscopy and endotracheal intubation and shown cardio-protective effect.