Effect of Oral Melatonin, Oral Clonidine and Oral Pregabalin Premedication on Attenuation of Hemodynamic Response to Direct Laryngoscopy and Tracheal Intubation

Laryngoscopy and endotracheal intubation are essential procedures required in elective case as well as emergency resuscitative settings. It is required to secure patients airway as well as to provide oxygenation and ventilation. Despite being a critical part of anaesthesia, it is still not free from hazard. These two are considered as noxious stimuli. Laryngoscopy alone generates same pressor response as can be seen by laryngoscopy followed by intubation. Hemodynamic stress response from airway instrumentation are due to sympathetic adrenergic response caused by epi pharyngeal and para pharyngeal stimulation leading to significant rise in the catecholamine level. This leads to various responses in various physiological systems of the body such as tachycardia, hypertension, arrhythmia, bronchospasm, increased intracranial pressure, elevation in intraocular pressure, etc. These hemodynamic changes usually peak at 1 to 2 min following laryngoscopy and tracheal intubation, and persist for 5–10 mins. Various methods to attenuate sympathetic response to laryngoscopy and tracheal intubation are being used and research for better drug is going on. All the above mentioned drugs have shown beneficial effects of blunting hemodynamic responses to laryngoscopy and tracheal intubation.