Dexmedetomidine and clonidine as an adjuvant to epidural anaesthesia: A prospective randomized, double blind study of their effect on postoperative sensory and motor block characteristics.

ABSTRACT

Background: Many researchers have been done to find an ideal adjuvant to ropivacaine in regional anaesthesia that inhibits intra and post-operative pain and prolong the duration of anaesthesia without any side effects. Aim: This study was conducted to evaluate the onset, extent and duration of sensory and motor block and side effects of clonidine or dexmedetomidine when used as an adjuvant to ropivacaine in epidural anaesthesia in lower limb orthopaedic surgery. Methods: A prospective randomized study was conducted on 60 patients of American society of anaesthesiologists’ status I and II, posted for lower limb orthopaedic surgery. All patients were randomly allocated into two groups of 30 each; group I was ropivacaine - clonidine group (RC) and group II was ropivacaine - dexmedetomidine group (RD). Group I (RC) patients received 16 ml of 0.75% ropivacaine and clonidine 2 mcg/kg. Group II (RD) patients received 16 ml of 0.75% ropivacaine and dexmedetomidine 1.5 mcg/kg. The onset, extent, duration of sensory and motor blocks, and side effects were recorded. Results: Dexmedetomidine had a visible edge over clonidine as it enabled an earlier onset and longer duration of sensory and motor block. Sedation scores were statistically significant with the RD group in comparison to RC group. The RD group showed visible superiority over the RC group in various post-operative block characteristics like the weaning of sensory and motor block, prolonged post-operative analgesia. Conclusion: Dexmedetomidine was a better alternative to clonidine as an adjuvant to ropivacaine in epidural anaesthesia in orthopaedic lower limb surgeries.