Efficacy of Intravenous Lignocaine 2% versus Oropharyngeal Topical 10% Xylocaine Spray before Induction of Anaesthesia in Attenuating the Pressor Response to Direct Laryngoscopy and Endotracheal Intubation

Background: Laryngoscopy and endotracheal intubation has been a challenging procedure due to associated cardiovascular changes called pressor response. To attenuate pressor response, drug that tends to block the response to airways instrumentation or those having antihypertensive response may be used. Lignocaine is a common local anesthetic and antiarrhythmic drug. It has been used both topically and intravenously for the attenuation of the pressor response to laryngoscopy and intubation. Objective of the study: To compare the efficacy of intravenous lignocaine 2 % versus oropharyngeal topical 10 % xylocaine spray before induction of anaesthesia in attenuating the pressor response to direct laryngoscopy and endotracheal intubation. Material and Methods: A total of 60 patients were divided randomly into two groups of 30 patients each. Group I received intravenous lignocaine 2 % @ 1.5 mg/kg. Group II received topical 10 % xylocaine spray @ 1.5 mg/kg body weight just before induction of anaesthesia. All hemodynamic parameters was measured immediately after laryngoscopy and intubation and at 1, 3, 5 minutes after laryngoscopy and intubation in both the groups. Results: Mean values of haemodynamic parameters in Group I increased after intubation and then started declining but did not reach the baseline even at 5 minutes. In Group II all mean values of haemodynamic parameters increased after intubation and then started declining to almost baseline at 5 minutes. The differences in mean values of haemodynamic between the two groups immediately after intubation and at 1, 3 and 5 minutes thereafter were statistically highly significant (p