Comparison of Intravenous Lignocaine and Dexmedetomidine for Attenuation of Hemodynamic Stress Response to Laryngoscopy and Endotracheal Intubation

Abstract

BACKGROUND The purpose of the present study was to evaluate the efficacy of intravenous lignocaine 1.5 mg / kg & intravenous dexmedetomidine 1 mcg / kg for attenuating the haemodynamic response to laryngoscopy & endotracheal intubation in patients undergoing elective surgery under general anaesthesia. METHODS In this prospective randomised, comparative, clinical study, 60 patients were randomly divided into 2 groups, among them 30 patients were given infusion of 1.5 mg / kg IV lignocaine, diluted to 10 ml with normal saline, 3 minutes before intubation & 30 patients were given infusion of dexmedetomidine 1 mcg / kg diluted to 25 ml in normal saline over 10 minutes through infusion pump before induction. The heart rate, systolic blood pressure, diastolic blood pressure, mean arterial pressure, rate pressure product, oxygen saturation were measured at baseline, after study drug intubation at L + 1, L + 3, L + 5, L + 7 & L + 10 (L is onset of laryngoscopy). Statistical analysis was done by using descriptive & inferential statistics using chisquare test, Students paired & unpaired t test to find out the significance of the five variables namely mean heart rate (HR), mean systolic blood pressure (SBP), mean diastolic blood pressure (DBP), mean arterial pressure (MAP) and mean rate pressure product (RPP). RESULTS Dexmedetomidine provided better blunting of stress response during laryngoscopy and intubation without causing clinically significant respiratory depression, bradycardia or hypotension. It is better in achieving a low RPP, which is a good predictor of myocardial oxygen consumption. Dexmedetomidine provides better cardio-protection in patients against pressure response than lignocaine. CONCLUSIONS In these 60 patients, dexmedetomidine (1 mcg / kg) was found to be superior to lignocaine (1.5 mg / kg) for attenuation of pressor response. KEY WORDS Laryngoscopy, Endotracheal Intubation, Dexmedetomidine, Lignocaine, Rate Pressure Product