A comparative study of intravenous esmolol, labetalol and lignocaine in low doses for attenuation of sympathomimetic responses to laryngoscopy and endotracheal intubation

Direct layngoscopy and endotracheal intubation is a noxious stimuli and induces sympathomimetic responses. Although well tolerated in healthy subjects, it may impose life threatening arrhythmias, left ventricular failure or rupture of cerebral aneurysm in susceptible patients. Esmolol, Labetalol and Lignocaine attenuate these responses but are associated with side effects of bradycardia, hypotension etc. In lower doses, chances of these side effects are comparatively low. So we designed this prospective clinical trial to assess the efficacy of intravenous esmolol, labetalol and lignocaine in low doses for attenuation of sympathomimetic responses to endotracheal intubation.