A Comparative study for post-operative pain relief after lumbar epidural block using 0.2% Ropivacaine with two different doses of Ketamine for lower abdominal and lower limb surgeries

Abstract

Background & Objective: By conducting this study our motive was to use a Local Anaesthetic like Ropivacaine which is very potent at lower doses and at the same time being less neurotoxic and cardiotoxic and having lower propensity of motor blockade. Simultaneously choosing an adjuvant like Ketamine which is non-opioid thus avoiding all opioid related side effects like respiratory depression,pruritis,nausea and vomiting. Our objective was to give lumbar epidural blockade with Ropivacaine (0.2%) with two different doses of Ketamine (0.3 mg/kg and 0.5 mg/kg) in all lower abdominal and lower limb surgeries and to observe onset and duration of analgesia, quality of post-operative analgesia, hemodynamic changes, side effects and complications. Methods: This prospective study was carried out involving randomly allocated 60 patients scheduled to undergo elective surgeries of lower abdomen and lower limb. They were randomly distributed into following groups of 30 each. The Group 1 and Group 2 patients were given 5ml (0.2%) Ropivacaine with 0.3 mg/kg and 0.5 mg/kg preservative free Ketamine via lumbar epidural catheter post operatively. The level of postoperative pain was assessed up to 48 hours(h) at intervals of 1h, 2h, 3h, 4h, 5h, 6h, 12h, 24h and 48h following surgery, using visual analogue scale (VAS). Whenever the VAS score was 4 or above epidural was charged accordingly. Results and Conclusion: In our present study the VAS score average was significantly lower in group 2 in which we administered 5ml (0.2%) Ropivacaine + 0.5 mg/kg Ketamine than group 1 in which we administered 5ml (0.2%) Ropivacaine + 0.3 mg/kg Ketamine at different intervals up to 48 hours. It was found that difference in mean VAS scores was significant only after 4 hours. In group 1 at 4 hours the average VAS score was 2.53±1.479. In group 2 at 4 hours the average VAS score was 1.23±2.112. We Concluded that adding Ketamine (Preservative free) to Ropivacaine(0.2%) improves the Post-operative pain outcome without any systemic side effects.