Comparative Evaluation Of Gabapentin, Clonidine And Combination Of Both The Drugs To Attenuate The Pressor Response To Direct Laryngoscopy And Intubation.

Background: The aim of our study was to compare the relative effectiveness of gabapentin and clonidine in attenuation of pressor response to direct laryngoscopy and intubation, and to evaluate the synergistic effect of combination of both drugs.Materials and methods: 120 patients of either sex of age between 20-60 years of American Society of Anaesthesiologist (ASA) grade I and II admitted 24 hours before elective surgery requiring general anaesthesia (GA) were included in the study. Patients were randomly allocated into four groups of 30 patients each: patients received oral 800 mg of gabapentin (group A), 300 μg of clonidine (group B), 400 mg of gabapentin and 150μg of clonidine (group C) and placebo (group D); 60 minutes (min.) prior to induction of anaesthesia. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial blood pressure (MAP) were measured before induction, intubation and at 0,1,3,5 and 10 minutes after intubation.Results: Analysis revealed that there was significant rise in HR at 0 minute in all the groups (p<0.05) except in group B. It remained to significant levels in group C and D up to 10 minutes (p<0.001 and p<0.01) but in group A it returned to insignificant level at 3 minutes. There was statistically highly significant rise in SBP, DBP and MAP (p<0.001,p<0.001 and p<0.01) in all the groups except in group A. In group A statistically significant (p<0.001) fall in SBP, DBP and MAP continued up to 10 minutes.Conclusion: Given 60 minutes before induction of GA, oral gabapentin and clonidine in the dose of 800mg and 300μg attenuate the pressor response but gabapentin blunts the increase in arterial blood pressure better than clonidine. The combination of these two drugs in the studied dosage was not effective in attenuating the pressor response to laryngoscopy and intubation.