EFFICACY OF ANESTHETIC COCKTAIL WOUND INSTILLATION FOR POSTOPERATIVE ANALGESIA FOLLOWING POSTERIOR SPINAL SURGERY

Abstract

Background: Posterior spinal surgery is a common procedure in orthopedic practices that causes severe pain after surgery. Proper postoperative pain controls not only benefit early mobilization and initiation of physiotherapy but they also play important roles in reducing morbidity and mortality.
 Objective: This prospective, double-blinded, randomized controlled study investigated the efficacy of anesthetic cocktail wound instillation for postoperative analgesia following posterior spinal surgery.
 Methods: After posterior spinal surgery, 54 patients were randomized to instill 20 mL of normal saline (Group N) or anesthetic cocktail consisting bupivacaine, ketorolac and morphine (Group A) in the wound after securing hemostasis and leaving a contact time of 60 seconds. After a dwell time of 60 seconds, the wound layers were closed without mopping or suctioning. All patients in both groups received patient-controlled analgesia using morphine for 24 hours post surgery, followed by standard analgesia. The analgesia consumption (morphine), visual analog scale (VAS) at specific hours after the operation, and time for first demand of analgesia were recorded. Morphine-related side effects were also monitored.
 Results: The patients in group A consumed significantly less morphine at 4, 8, 12 and 16 hours after the surgery (p=0.048, 0.007, 0.005 and 0.026, respectively). In addition, they had lower VAS over the first 24 hours (p<0.05) and longer median duration of first demand of analgesia (p=0.013). Morphinerelated side effects were also lower in group A (p=0.024). Conclusion: The simple technique of wound instillation with anesthetic cocktail significantly reduced postoperative requirements of morphine and improved pain control with lower rates of nausea and vomiting over the first postoperative day after posterior spinal surgery.