Authors: Mohan K, Mohana Rupa L
The study has been designed to investigate the attenuation of cardiovascular responses to laryngoscopy and intubation by diltiazem and lignocaine. Endotracheal intubation is often associated with a hypertension and tachycardia. This response is primarily because of sympatho-adrenal stimulation, associated with laryngoscopy and endotracheal intubation. The rise in the heart rate (HR) and blood pressure increases the myocardial oxygen demand. This increase is tolerated well by normal healthy individuals. However, in patients with Ischemic heart disease (IHD), Hypertensive heart disease and cerebrovascular disease, this sudden rise of heart rate and blood pressure can produce deleterious effects, in the form of myocardial ischemia, pulmonary oedema and cerebral haemorrhage. Many methods, like beta-blockers, deep inhalational anaesthesia, intravenous lignocaine, calcium channel blockers and direct acting vasodilators, have been tried to blunt these harmful pressor responses associated with laryngoscopy and endotracheal intubation. Intravenous lignocaine is a popular method of blunting this response, because of its ability to depress the myocardium and membrane stabilization effect. Diltiazem, a calcium channel blocker can blunt these responses because of its direct acting vasodilating properties and negative chronotropic effect. In view of it, the present study was undertaken to compare the effects of 1.5 mg/kg lignocaine IV given 3 minutes before laryngoscopy and intubation, Diltiazem 0.2 mg/kg IV given 60 seconds before laryngoscopy and intubation and combination of 0.2 mg/kg of diltiazem IV and 1.5 mg/kg of lignocaine IV given 60 seconds before laryngoscope and intubation on laryngoscopic reactions. It was noted that,both lignocaine and diltiazem attenuated the pressor response to laryngoscopy and endotracheal intubation compared to control group. However, the combination of lignocaine and diltiazem gave better protection against the laryngoscopic reaction than when either of the drugs was given alone.
Keywords: Laryngoscopy, tracheal intubation, cardiovascular response, Lignocaine, Diltiazem