Comparison of dexmedetomidine and clonidine as an adjuvant to lignocaine with adrenaline in infiltration anesthesia for tympanoplasty

Background: Adjuvants to local anesthetics enhance the quality and duration of analgesia. Dexmedetomidine, a potent alpha 2-adrenoceptor agonist, is approximately eight times more selective towards the alpha 2-adrenoceptor than clonidine. Dexmedetomidine was compared with clonidine in infiltration anesthesia when added to local anesthetic in infiltration anesthesia in tympanoplasty. Methodology: Sixty patients of age group 18-60 years, scheduled for tympanoplasty under local anesthesia were randomly divided into two equal groups. In Group C (n = 30), 12 ml of 2% lignocaine with adrenaline + clonidine 1 mu g/kg; and in Group D (n = 30), 12 ml of 2% lignocaine with adrenaline + dexmedetomidine 1 mu g/kg were infiltrated. Onset and duration of analgesia, hemodynamic parameters, sedation score and grade of bleeding were recorded. All the Quantitative data are presented as mean and standard deviation and compared using student's t-test. Qualitative data such as sedation score, grade of bleeding are presented as frequency and percentage and analyzed using chi-square test. P-value of < 0.05 was considered as significant and p < 0.001 was considered as highly significant. Results: Both groups were comparable in terms of demographic and surgical parameters. Duration of postoperative analgesia was lasted longer in Group D as compare to Group C (690.00 +/- 80.12 vs 417.67 +/- 58.64 min, P < 0.001) and sedation scores were higher in Group D. No difference was observed in both of the groups regarding other parameters including onset of analgesia, mean pulse rate, mean blood pressure and grade of bleeding at different time intervals (P > 0.05). Conclusion: Dexmedetomidine when used as an adjuvant to local anesthetic in infiltration anesthesia for tympanoplasty was found to be more effective than clonidine in terms of duration of postoperative analgesia and sedation score, with no difference in terms of onset of analgesia, grade of bleeding and hemodynamic parameters.