Intrathecal morphine injections in lumbar fusion surgery: Case-control study

Introduction: Intrathecal morphine (ITM) is a well-known and extensively used method for analgesia in various surgical fields; however, its relevance in spine surgery is debated given the conflicting results in the literature. The aim of this study was to investigate the opioid-sparing effect of ITM after lumbar fusion. Methods: This retrospective study involves two consecutive series of patients undergoing posterior lumbar fusion. The first cohort (control group, n= 30) received the standard analgesia protocol while the second cohort (ITM Group, n= 30) had the standard protocol supplemented with ITM (100 mu g of morphine hydrochloride). Morphine consumption, pain assessment (VAS), specific complications and postoperative recovery data were collected. Results: Consumption of morphine at 24 hours and 48 hours postoperatively was lower in the ITM group than the control group (p < 0.001 and p = 0.004). The pattern was similar for pain on VAS at H6, H24 and H36 (p = 0.001; p = 0.003 and p = 0.01). The patients in the ITM group were able to get out of bed faster than the controls (1.13 days vs 1.83 days, p = 0.002) and the discharge was earlier in the ITM group (5.1 days vs. 6.2 days, p = 0.002). There was no difference in morphine-specific complications between the two groups. Conclusion: Adding ITM to the analgesia protocol for lumbar fusion provides better management of post-operative pain, without increasing early complications, and it accelerates the recovery process after surgery. (C) 2020 Elsevier Masson SAS. All rights reserved.