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 (100μg of morphine hydrochloride). Morphine consumption, pain assessment (VAS), specific complications and postoperative recovery data were collected.

Results:

Consumption of morphine at 24hours and 48hours 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 postoperative pain, without increasing early complications, and it accelerates the recovery process after surgery.

Level of evidence:

IV.