Comparison of dexmedetomidine and clonidine as an adjuvant to ropivacaine for epidural anesthesia in lower abdominal and lower limb surgeries

Background: The quality and duration of analgesia is improved when a local anesthetic is combined with alpha 2 adrenergic agonist. Though, the effects of clonidine on local anesthetics have been extensively studied, there are limited studies demonstrating the effects of epidural dexmedetomidine on local anesthetics. The aim of our study is to compare the effect of clonidine and dexmedetomidine when used as an adjuvant to epidural ropivacaine in lower abdominal and lower limb surgeries. Materials and Methods: Patients were randomized into two groups-group ropivacaine with clonidine (RC) received 15 ml of 0.75% ropivacaine with 1 mu g/kg clonidine and group ropivacaine with dexmedetomidine (RD) received 15 ml of 0.75% ropivacaine with 1 mu g/kg dexmedetomidine epidurally. Onset of sensory analgesia using cold swab, onset of motor blockade using Bromage scale, time to 2 dermatome regression of sensory level, time to first demand for analgesia, sedation using Ramsay sedation scale, intra operative hemodynamic parameters and complications were assessed. Results: The onset (RD-8.53 +/- 1.81, RC-11.93 +/- 1.96) and duration of sensory blockade (RD-316 +/- 31.5, RC-281 +/- 37, sedation were found to be significantly better in the dexmedetomidine group. No significant difference was found in terms of onset of motor blockade and hemodynamic changes. Conclusion: Dexmedetomidine at doses of 1 mu g/kg is an effective adjuvant to ropivacaine for epidural anesthesia, which is comparable to clonidine.