Cardiovascular response to endotracheal extubation with and without injection of lidocaine

ABSTRACT

The hemodynamic responses to endotracheal extubation and efficacy of I.V. lidocaine pretreatment were studied after intraocular surgery. Twenty patients were divided into two equal groups Group 1; patients who had placebo, group 2; patients who received lidocaine 1.5 mg.kg-1 before tracheal extubation. Hemodynamic data, electrocardiographic tracings were obtained at the end of surgery during suctioning and 1, 3, 5 min after tracheal extubation. Group 1 patients displayed significant increases in HR, SAP, DAP, MAP and RPP during suctioning and within 1, 3, 5 min after tracheal extubation. Two patients showed evidence of myocardial ischemia on ECG after extubation which was self limited and of short duration. Ventricular extrasystoles were observed during extubation in 1 patient. In lidocaine treated patients [group 2], the increases in HR, SAP, DAP, MAP and RPP were completely attenuated during suctioning and within 1 min of extubation. No patient in this group revealed evidence of myocardial ischemia or cardiac dysrhythmias. The results show the beneficial effects of I.V. lidocaine in preventing coughing, laryngospasm and increases in arterial blood pressure, heart rate during and after extubation