Early prediction model of organ/space surgical site infection after elective gastrointestinal or hepatopancreatobiliary cancer surgery

Organ/space SSI is a significant clinical problem. However, early detection of organ/space SSI is difficult, and previous predictive models are limited in their prognostic ability. We aimed to develop and validate a prediction model of organ/space surgical site infection (SSI) using postoperative day 3 laboratory data in patients who underwent gastrointestinal or hepatopancreatobiliary cancer resection. This retrospective cohort study using a single-center hospital data from April 2013 to September 2017 included all adult patients who underwent elective gastrointestinal or hepatopancreatobiliary cancer resection. The primary outcome was a presence of organ/space SSI including anastomotic leakage, pancreatic fistula, biliary fistula, or intra-abdominal abscess. We developed and validated a logistic regression model to predict organ/space SSI using laboratory data on postoperative day (POD) 3. Similar models using laboratory data on POD 1 or 5 were developed to compare the predictive ability of each model. A total of 1578 patients were included. Organ/space SSI was diagnosed in 107 patients, with median diagnosis days of 6 (interquartile range, 4–9 days) after surgery. A prediction model using five commonly measured variables on POD 3 was created with the area under the curve (AUC) of 0.883 (95%CI 0.819–0.946). The AUC of a model with POD 1 laboratory data was 0.751 (95%CI 0.655–0.848), while that of POD 5 laboratory data was 0.818 (95%CI 0.730–0.906). Laboratory data on POD 3 could forecast organ/space SSI precisely. Further prospective studies are warranted to investigate the clinical impact of this model.