BOWEL PREPARATION FOR ELECTIVE COLORECTAL RESECTION: MULTI-TREATMENT MACHINE LEARNING ANALYSIS ON 6,241 CASES FROM A PROSEPCTIVE ITALIAN COHORT

Objective: To compare the incidence of anastomotic leakage (AL), surgical site infections (SSIs), and overall morbidity (OM) after elective colorectal surgery using four different types of bowel preparation.
Summary Background Data: Current evidence and guidelines concerning bowel preparation before elective colorectal surgery are still controversial.
Methods: A database gathered among 78 Italian surgical centers in two prospective studies, including 6,241 patients who underwent elective colorectal resection with anastomosis for malignant or benign disease, was retrospectively analyzed through a multi-treatment machine learning model (Generalized Boosted Model) considering no bowel preparation (NBP; No.=3,742; 60.0%) as the reference treatment arm, compared to oral antibiotics alone (oA; No.=406; 6.5%), mechanical bowel preparation alone (MBP; No.=1,486; 23.8%) or in combination with oAB (MoABP; No.=607; 9.7%). Twenty covariates related to biometric data, surgical procedures, perioperative management, and hospital/center data potentially affecting outcomes were included and balanced into the model. The primary endpoints were AL, SSIs, and OM. All the results were reported as odds ratio (OR) with 95% confidence intervals (95%CI)
Results: Compared to NBP, MBP showed significantly higher AL risk (OR 1.82; 95%CI 1.23-2.71; p = .003) and OM risk (OR 1.38; 95%CI 1.10-1.72; p = .005), oA no significant differences for all the endpoints, whereas MoABP showed a significantly reduced SSIs risk (OR 0.45; 95%CI 0.25-0.79; p = .008).
Conclusions: MoABP significantly reduced the SSIs risk after elective colorectal surgery, therefore representing a valid alternative to NBP, while MBP alone should be abandoned or replaced by MoABP.