1276. Outcomes Following Use of Spinal Morphine Analgesia in Lumbar Spine Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Studies

Award: Third Place Pain Eposter Award

Authors: Mohamad Bydon, MD, FAANS ; Anshit Goyal, MBBS; Elena Blaginykh, MD, MPH; Waseem Wahood, MS; Mohammed Alvi, MBBS (Rochester, MN)

Introduction: Epidural and intrathecal opioids are effective means of postoperative analgesia in lumbar spine surgery. However, their use is limited by adverse events such as respiratory depression. We performed a systematic review and meta-analysis of current randomized controlled studies to compare outcomes following use of spinal morphine against other intraoperative analgesic alternatives. Methods: A literature search was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for article screening and inclusion. We included prospective randomized studies with at least 5 adult (>18) patients in each group undergoing lumbar spine surgery with use of either spinal (intrathecal or epidural) morphine or other analgesic alternatives for post-operative pain control. Given heterogeneity in control groups, random-effects meta-analysis was performed to compare outcomes such as complication rates, postoperative analgesic requirements and pain control as measured by the Visual Analog Scale (VAS-BP). Results: Seven studies (n=592 patients) were included with 376 (63.5%) receiving spinal morphine. All patients received postoperative narcotics either by patient controlled analgesia or on-demand parenteral administration. Compared to controls (local anesthetic/no morphine /normal saline) patients receiving intrathecal/epidural morphine showed lower postoperative VAS scores (Mean Difference (SMD): -0.31,CI:-0.94to0.33, p<0.001, I2=89%) and opioid analgesic requirements (SMD: -1.92,CI: -3.74to-0.11, p<0.001, I2=96%). No difference was observed in rate of nausea/vomiting (OR: 0.93, CI: 0.25-3.49, p=0.91, I2=84%), urinary retention (OR: 1.67, CI:0.80-3.48, p=0.17, I2=44%) and apneic episodes (OR: 1.21,CI: 0.33-4.51, p=0.77, I2=53%). However, pruritus (OR: 4.56,CI: 2.3-9.04, p<0.001, I2=0%) was found to be higher with spinal administration of morphine. Conclusion: Use of intrathecal and epidural morphine may be associated with improved post-operative pain control and decreased postoperative analgesic requirements with a safety profile comparable to other intraoperative analgesic alternatives.