The impact of perioperative opioid use on post-operative outcomes following spinal surgery: A meta-analysis of 60 cohort studies with 13 million participants.

BACKGROUND CONTEXT: An important factor for the prognosis of spinal surgery is the perioperative use of opioids. However, the relationship is not clear.

PURPOSE: The purpose of this study was to evaluate the effect of perioperative opioid use on the prognosis of patients following spinal surgery.

STUDY DESIGN/SETTING: Systematic review and meta-analysis.

OUTCOME MEASURES: A meta-analysis was conducted using the random-effects method to calculate pooled odds ratios (ORs) with 95% confidence intervals (CIs).

METHODS: The PubMed, Embase, and Cochrane Library databases were systematically searched to find relevant articles that were published until September 2, 2022. The primary outcome was prolonged post-operative opioid use, and secondary outcomes included the length of stay (LOS), reoperation, the time to return to work (RTW), post-operative complications, gastrointestinal complications, new permanent disability, central nervous system events and infection. In addition, subgroup analysis of the primary outcome was conducted to explore the main sources of heterogeneity, and sensitivity analysis of all outcomes was performed to evaluate the stability of the results.

RESULTS: A total of 60 cohort studies involving 13,219,228 individuals met the inclusion criteria. Meta-analysis showed that perioperative opioid use was specifically related to prolonged post-operative opioid use (OR 6.91, 95% CI 6.09 to 7.84, P < 0.01). Furthermore, the results also showed that perioperative opioid use was significantly associated with prolonged LOS (OR 1.74, 95% CI 1.39 to 2.18, P < 0.01), post-operative complications (OR 1.72, 95% CI 1.26 to 2.36, P < 0.01), reoperation (OR 2.38, 95% CI 1.85 to 3.07, P < 0.01), the time to RTW (OR 0.45, 95% CI 0.39 to 0.52, P < 0.01), gastrointestinal complications (OR 1.39, 95% CI 1.30 to 1.48, P < 0.01), central nervous system events (OR 1.99, 95% CI 1.21 to 3.27, P = 0.07) and infection (OR 1.22, 95% CI 1.09 to 1.36, P = 0.01). These results were corroborated by the trim-and-fill procedure and leave-one-out sensitivity analyses.

CONCLUSION: Based on the current evidence, patients with perioperative opioid use, in comparison to controls, appear to have prolonged postoperative opioid use, which may increase the risk of poor outcomes including prolonged LOS, complications, reoperation, RTW and so on. However, these results must be carefully interpreted as the number of studies included was small and the studies were statistically heterogeneous. These findings may help clinicians to realize the harmfulness of perioperative use of opioids, reduce the use of prescription opioids, necessarily withdraw before operation or significantly wean to the lowest tolerable preoperative amount, and provide some inspiration for standardizing the use of opioids in the future.