Background We evaluated the impact of bilateral ultrasound-guided erector spinae plane blocks on pain and opioid-related outcomes within a standardized care pathway for lumbar fusion.

Methods A retrospective propensity score matched cohort study. Clinical data were extracted from the electronic medical records of patients who underwent lumbar fusion (January 2019–July 2020). Propensity score matching based on common confounders was used to match patients who received or did not receive blocks in a 1:1 ratio. Primary outcomes were Numeric Rating Scale pain scores (0–10) and opioid consumption (morphine equivalent dose) in the first 24 hours after surgery (median (IQR)). Secondary outcomes included length of stay and opioid-related side effects.

Results Of 1846 patients identified, 242 were matched and analyzed. Total 24-hour opioid consumption was significantly lower in the erector spinae plane block group (30 mg (0, 144); without-blocks: 45 mg (0, 225); p=0.03). There were no significant differences in pain scores in the postanesthesia care unit (with blocks: 4 (0, 9); without blocks: 4 (0,8); p=0.984) or on the nursing floor (with blocks: 4 (0,8); without blocks: 4 (0,8); p=0.134). Total length of stay was 5 hours shorter in the block group (76 hours (21, 411); without blocks: 81 (25, 268); p=0.001). Fewer patients who received blocks required postoperative antiemetic administration (with blocks: n=77 (64%); without blocks: n=97 (80%); p=0.006).

Conclusions Erector spinae plane blocks were associated with clinically irrelevant reductions in 24-hour opioid consumption and no improvement in pain scores after lumbar fusion. The routine use of these blocks in the setting of a comprehensive care pathway for lumbar fusion may not be warranted.