The unequal impact of interhospital transfers on emergency general surgery patients: Procedure risk and time to surgery matter

BACKGROUND The impact of interhospital transfer on outcomes of patients undergoing emergency general surgery (EGS) procedures is incompletely studied. We set out to determine if transfer before definitive surgical care leads to worse outcomes in EGS patients. METHODS Using the National Surgical Quality Improvement Project database (2013-2019), a retrospective cohort study was conducted including nine surgical procedures encompassing 80% of the burden of EGS diseases, performed on an urgent/emergent basis. The procedures were classified as low risk (open and laparoscopic appendectomy and laparoscopic cholecystectomy) and high risk (open cholecystectomy, laparoscopic and open colectomy, lysis of adhesions, perforated ulcer repair, small bowel resection, and exploratory laparotomy). Time to surgery was recorded in days. The impact of interhospital transfer on outcomes (mortality, major complications, 30-day reoperations, and 30-day readmissions) and length of stay, according to procedure risk and time to surgery, were analyzed by multivariate logistic regression and inverse probability treatment of the weighting with treatment effect in the treated. RESULTS A total of 329,613 patients were included in the study (284,783 direct admission and 44,830 transfers). Adjusted mortality (3.1% vs. 10.4%; adjusted odds ratio [AOR], 1.28; p < 0.001), major complications (6.7% vs. 18.9%; AOR, 1.39; p < 0.001), 30-day reoperations (3.1% vs. 6.4%; AOR, 1.22; p < 0.001), and length of stay (2 vs. 5) were higher in transferred patients. Transfer had no effect on 30-day readmissions (6% vs. 8.5%; AOR, 1.04; p = 0.063). These results were also observed in high-risk surgery patients and in the late surgery group. The results were further confirmed after robust propensity score weighting was performed. CONCLUSION We have demonstrated that delays to surgical intervention affect outcomes and that interhospital transfer of EGS patients for definitive surgical care has a negative impact on mortality, development of postoperative complications, and reoperations in patients undergoing high-risk EGS procedures. These findings may have important implications for regionalization of EGS care.LEVEL OF EVIDENCEPrognostic/epidemiological, level III.