Development of a simple model for predicting need for surgery in patients who initially undergo conservative management for adhesive small bowel obstruction.

BACKGROUND Among patients with adhesive small bowel obstruction (ASBO) initially managed with a conservative strategy, predicting risk of operation is difficult. METHODS We investigated ASBO patients at 2 different periods to derive and validate a clinical prediction model for risk of operation. RESULTS One hundred fifty-four patients were enrolled into the derivation cohort and 96 into the validation cohort. Based on the derived scoring, including age > or =65 years, presence of ascites, and gastrointestinal drainage volume >500 mL on day 3, each patient was classified into 1 of 4 risk classes from low risk to high risk. When applied to the validation cohort, the positive predictive value (PPV) for operation in the high-risk class was 72%, while the negative predictive value (NPV) in the low-risk class was 100% with high sensitivity (100%) and specificity (96%). CONCLUSIONS The prediction model performs well for risk stratification of need for surgical intervention following conservative strategy among ASBO patients.