Preoperative drug dispensing as predictor of surgical site infection

The system used by the National Nosocomial Infection Surveillance (NNIS) pr ogram to measure risk of surgical site infection uses a score of 3 on the A merican Society of Anesthesiologists (ASA)-physical status scale as a measu re of underlying illness. The chronic disease score measures health status as a function of age, sex, and 29 chronic diseases, inferred from dispensin g of prescription drugs. We studied the relationship between the chronic di sease score and surgical site infection and whether the score can supplemen t the NNIS risk index. In a retrospective comparison of 191 patients with s urgical site infection and 378 uninfected controls, the chronic disease sco re and ASA score were highly correlated. The chronic disease score improved prediction of infection by the NNIS risk index and augmented the ASA score for risk adjustment.