Our experience in comparative evaluation of dexmedetomidine and ketamine for epidural analgesia in lower limb orthopedic surgeries

Abstract

Introduction: The combined spinal epidural anesthesia (CSE) plays a unique role in management of perioperative analgesia. It is associated with early postoperative mobilization and rehabilitation with minimally associated pain and discomfort, which is the most desirable feature in modern surgery. We designed this study for comparative evaluation of dexmedetomidine and ketamine for epidural analgesia in lower limb orthopedic surgeries in patients operated under CSE. Materials and Methods: The study included 50 patients divided into two groups (25 each). Group D: Patient received bolus dose of dexmedetomidine 1 µg/kg after spinal anesthesia followed by bupivacaine 0.125% with dexmedetomidine 1 µg/ml epidurally using 240 ml elastomeric pump at 5ml/ hr till 48 hours. Group K: Patient received bolus dose of ketamine 0.5 mg/kg after spinal anesthesia followed bupivacaine 0.125% with ketamine 0.5mg/ml epidurally using elastomeric pump at 5ml/hr till 48 hours. Results: There was no significant difference between the two groups (p>0.05) in terms of highest sensory level achieved and time for complete motor block. The patients in both the groups were hemodynamicaly stable throughout the study. The duration of analgesia was longer with dexmedetomidine however, none of the patients in both the groups required rescue analgesic. The time to regression of sensory level to L5 in Group D was found to be 594 ± 63.04 minutes as compared to 362.4 ± 45.76 minutes in Group K (p<.001) while, the time to regression of motor block to Bromage scale 1 in Group D was 488.4 ± 42.88 minutes whereas, in Group K it was 303.6 ± 36.04 minutes (p<0.001). The incidence of sedation, nausea, vomiting and other side effects were comparable. Conclusion: We conclude that continuous epidural infusion with dexmedetomidine and ketamine effectively reduced the postoperative rescue analgesics requirements and provided good patient satisfaction in patients undergoing lower limb orthopedic surgery.