Efficacy of Intra operative Combined Epidural and Intramuscular (back muscle) Bupivacaine Injection for Post-Operative Pain Assessment in Lumbar Spine Surgery

Background: Spine surgery patients often experience severe postoperative pain from nociceptive, neuropathic, and inflammatory mechanisms. Local anesthetics like lidocaine and bupivacaine reduce pain, opioid use, and costs by blocking nerve signals but may increase resource expenses. Objectives: to evaluate the efficacy of intra-operative combined epidural and intramuscular bupivacaine injection for post-operative pain management after lumbar spine surgery Patients and methods: This randomized, double-blind study enrolled 60 spine surgery patients into two groups: a combined injection group and control group receiving a placebo. Standard monitoring and general anesthesia were done. The treatment group received 7 ml of bupivacaine epidurally and 7 ml intramuscularly before wound closure. Pain was assessed at intervals up to 24 hours. Results: Demographic data showed non-significant differences between the 2 groups. Postoperative pain scores were significantly lower in the combined injection group at 2 hours (1.87±0.88 vs. 2.7±1.49, P=0.0391), 6 hours (2.23±1.58 vs. 4±1.79, P < 0.0001), 18 hours (1.77±1.67 vs. 2.9±1.51, P=0.0019), and 24 hours (0.83±0.9 vs. 2.03±1.22, P=0.0002). The first request for analgesia was delayed in the combined group (5.2±3.82 vs. 3.8±5.25, P=0.0373), and a higher proportion required only one dose (63.33% vs. 30%, P=0.0091). Anxiety was absent in the combined group but present in 30% of the control group (P=0.0019). Conclusion: Combined intraoperative epidural and intramuscular bupivacaine significantly improves postoperative pain management in lumbar spine surgery patients and is associated with higher satisfaction with pain relief and mobility, along with fewer instances of anxiety and shorter hospital stay.