Addition of Ketorolac to Local Anesthesia for Wound Infiltration in Multilevel Posterior Lumbar Spinal Fusion

Study Design. Randomized double-blind controlled trial. Objective. The purpose of this study was to determine the efficacy of pain control and opioid consumption after administration of ketorolac directly to paraspinal muscle after spinal fusion. Summary of Background Data. Ketorolac is added to multimodal analgesia regimens to improve pain control, reduce opioid consumption following Orthopaedics and spine surgery. However, evidence of efficacy of adding ketorolac to local anesthesia for intrawound infiltration after spine surgery is still limited. Materials and Methods. The patients who underwent multilevel lumbar decompression and posterolateral fusion were recruited and randomized to the control group which received 0.5% bupivacaine hydrochloride injected into paraspinal muscles before wound closure, and the ketorolac group which received 30 mg ketorolac in addition to 0.5% bupivacaine hydrochloride. Post-operative numerical rating scale (NRS) for back pain, leg pain, morphine consumption, and adverse events were recorded. Results. A total of 47 patients were randomized (24 in the ketorolac group and 23 in the control group). The mean age was 60.9±6.9 years old. The mean NRS for back pain at 6 hours after surgery was 5.8±3.0 points for the control group and 3.3±2.1 points for the ketorolac group ( P <0.01). The ketorolac group consumed lesser morphine than the control group by 9.1 mg in the first 24 hours, 13.8 mg at 48 hours, 14.3 mg at 72 hours, and 13.9 mg at 96 hours after the surgery ( P <0.05). Post-operative complications were not different between the two groups. Conclusions. The addition of ketorolac to bupivacaine for wound infiltration after posterior lumbar spine decompression and fusion reduces early post-operative pain and total morphine consumption as compared to bupivacaine alone.