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DOI: http://dx.doi.org/10.21088/ijaa.2349.8471.5818.4

Abstract

This study was carried out to compare the effectiveness of I.V. nitroglycerine and clonidine for controlling the pressor response to laryngoscopy and endotracheal intubaltion during general anaesthesia. This study was done on 90 adult patients of either sex belonging to ASA grade-1, aged 20-50 years and were randomly allocated into three groups according to the agents to be used before induction of anaesthesia, comprising of 30 patients each. Group-1 : control group (not receiving any pre-medication), Group-2 : IV nitroglycerine, Group-3 : IV clonidine. All the patients were prepared with adequate pre operative fasting. Tablet alprazolam 0.5mg given orally night before surgery for quiet and calm sleep. After checking the patient’s blood pressure, H.R. and ECG at basal stage, pre-treatment was started. Group- 2 patients were pre-medicated with 200µg/min slow intravenous Nitroglycerine is given till the systolic blood pressure fell down by 20-30% of the basal. Group-3 patients were pre-treated with 0.3 mg of clonidine IV. Systolic arterial pressure, diastolic arterial pressure,mean arterial pressure, heart rate were measured at base line(3 min before induction), just before laryngoscopy and post intubation at 1, 3, 5, 10 and 15 min after laryngoscopy and intubation. Anaesthesia was maintained on nitrous oxide, oxygen, 0.5% isoflurane and a long acting muscle relaxant. While comparing inter-group comparison, it was observed that there was significant increase in heart rate in Group-1 and Group-2, but heart rate remains controlled and stable in group 3. Hence, it was found that nitroglycerine had no role in controlling the heart rate during intubation, whereas there was significant change in blood pressure in Group-2 and Group-3 as compared to Group-1. This suggests that nitroglycerine and clonidine effectively attenuates hypertensive response to laryngoscopy and intubation. ECG changes were observed in all the groups for sinus tachycardia. 

 

Keywords : Clonidine; Nitroglycerine; Laryngoscopy; Endotracheal Intubation; Pressor Response.

Corresponding Author : Ajai Vikram Singh, Associate Professor, Department of Anaesthesiology & Critical Care, Veer Chandra Singh Garhwali Government Institute Of Medical Science and Research (VCSGGMSRI), Srinagar, Garhwal, Uttarakhand 246174, India.