Prophylactic antibiotic bundle compliance and surgical site infections: an artificial neural network analysis

Best practice "bundles" have been developed to lower the occurrence rate of surgical site infections (SSI's). We developed artificial neural network (ANN) models to predict SSI occurrence based on prophylactic antibiotic compliance.

Using the American College of Surgeons National Quality Improvement Program (ACS-NSQIP) Tampa General Hospital patient dataset for a six-month period, 780 surgical procedures were reviewed for compliance with SSI guidelines for antibiotic type and timing. SSI rates were determined for patients in the compliant and non-compliant groups. ANN training and validation models were developed to include the variables of age, sex, steroid use, bleeding disorders, transfusion, white blood cell count, hematocrit level, platelet count, wound class, ASA class, and surgical antimicrobial prophylaxis (SAP) bundle compliance.

Overall compliance to recommended antibiotic type and timing was 92.0%. Antibiotic bundle compliance had a lower incidence of SSI's (3.3%) compared to the non-compliant group (8.1%, p = 0.07). ANN models predicted SSI with a 69-90% sensitivity and 50-60% specificity. The model was more sensitive when bundle compliance was not used in the model, but more specific when it was. Preoperative white blood cell (WBC) count had the most influence on the model.

SAP bundle compliance was associated with a lower incidence of SSI's. In an ANN model, inclusion of the SAP bundle compliance reduced sensitivity, but increased specificity of the prediction model. Preoperative WBC count had the most influence on the model.