Impact of the 2016 American College of Surgeons Guideline Revision on Overlapping Lumbar Fusion Cases at a Large Academic Medical Center

Abstract

The American College of Surgeons (ACS) updated its guidelines on overlapping surgery in 2016. The objective was to examine differences in postoperative outcomes after overlapping surgery either pre-ACS guideline revision or post-guideline revision, in a coarsened exact matching sample. A total of 3327 consecutive adult patients undergoing single-level posterior lumbar fusion from 2013 to 2019 were retrospectively analyzed. Patients were separated into a pre-ACS guideline revision cohort (surgery before April 2016) or a post-guideline revision cohort (surgery after October 2016) for comparison. The primary outcomes were proportion of cases performed with any degree of overlap, and adverse events including 30-day and 90-day rates of readmission, reoperation, emergency department visit, morbidity, and mortality. Subsequently, coarsened exact matching was used among overlapping surgery patients only to assess the impact of the ACS guideline revision on overlapping outcomes, and controlling for attending surgeon and key patient characteristics known to affect surgical outcomes. After the implementation of the ACS guidelines, fewer cases were performed with overlap (22.0% vs. 53.7%; P < 0.001). Patients in the post-ACS guideline revision cohort experienced improved rates of readmission and reoperation within 30 and 90 days. However, when limited to overlapping cases only, no differences were observed in overlap outcomes pre-ACS versus post-ACS guideline revision. Similarly, when exact matched on risk-associated patient characteristics and attending surgeon, overlapping surgery patients pre-ACS and post-ACS guideline revision experienced similar rates of 30-day and 90-day outcomes. After the ACS guideline revision, no discernable impact was observed on postoperative outcomes after lumbar fusion performed with overlap.