Beyond Core Measures: Identifying Modifiable Risk Factors for Prevention of Surgical Site Infection after Elective Total Abdominal Hysterectomy

Background: Despite adherence to the Centers for Medicare and Medicaid Services (CMS) core measures for preventing surgical site infections (SSI), our institution has a >10% rate of SSI after total abdominal hysterectomy (TAH), higher than the 90th percentile for SSI rates published in the 2009 National Healthcare Safety Network report. Methods: A retrospective chart review was performed for patients who underwent elective TAH at a public safety net hospital in Denver from December 30, 2005, to March 9, 2010. The primary outcome was development of SSI within 30 days. A secondary outcome was adherence to CMS core measures. Results: A total of 192 patients were included in the analysis, of whom 21 (10.9%) developed SSI. More than 95% had received antibiotics in the 60 min before surgical incision, and >90% received an appropriate antibiotic. Compliance with post-anesthesia care unit normothermia was equivalent in the SSI and non-SSI groups (81.0% vs. 75.2%; p = 0.5588). Surgical site infection was associated with obesity (body mass index [BMI] >= 30) (15.4% vs. 6.9%; p = 0.0609), estimated blood loss >= 500mL (18.5% vs. 8.0%; p = 0.0353), and receipt of a blood transfusion (28.6% vs. 10.5%; p = 0.0183). In a multiple logistic regression model, obesity marginally increased the risk of SSI (odds ratio [OR] 2.55; 95% confidence interval [CI] 0.94-6.74), whereas blood transfusion was significantly associated with a higher risk of SSI (OR 3.58; 95% CI 1.21-10.62). Conclusions: Blood transfusion was associated with SSI after TAH in our population. As it is a modifiable risk factor, larger multi-center studies are needed to confirm this result and determine appropriate transfusion thresholds.