A comparative study of analgesic effects of intrathecal hyperbaric ropivacaine with dexmedetomidine and hyperbaric ropivacaine with clonidine in lower abdominal surgery

Abstract

Background: Local anesthetics are often combined with adjuvants such as opioids and α2 agonists to improve or prolong the anesthetic effect. This study was taken up to compare the duration of postoperative analgesia between ropivacaine with clonidine and ropivacaine with dexmedetomidine. Materials and Methods: In this prospective, randomized, double-blinded study, 50 adult patients of both sexes undergoing lower abdominal surgeries under spinal anesthesia were allocated to two groups, C and D, by a computer-generated randomization table. Group C (clonidine group) received 2.5 mL of 0.75% hyperbaric ropivacaine with 50 μgm of clonidine (0.5 mL) and Group D (dexmedetomidine group) received 2.5 mL of 0.75% hyperbaric ropivacaine with 5 μgm of dexmedetomidine in 0.5 mL of normal saline. The spinal block characteristics, duration of surgery, duration of postoperative analgesia, first 24 h analgesic consumption, hemodynamic parameters, and adverse effects (if any) were recorded. Results: The time to S2 regression was significantly more with Group D (Group D vs Group C: 448.78 ± 41.52 vs 392.68 ± 38.72 min (P < 0.001). There was significant difference between Groups C and D in duration of analgesia (269.20 ± 51.61 vs 303.20 ± 48.65 min; P = 0.020) respectively. Analgesic consumption (in mg) in the first 24 h was statistically less in the dexmedetomidine group than in the clonidine group (248.00 ± 58.59 vs 312.00 ± 60 min; P < 0.001). The incidence of hypotension and bradycardia was: Group D vs Group C: 12 vs 10, 5:4, respectively. Conclusion: Dexmedetomidine as an adjuvant to ropivacaine spinal anesthesia, provided excellent quality of postoperative analgesia with minimal side effects in prolonged surgeries compared to clonidine.