03: Surgical site infection prevention bundle for hysterectomy: Effect on costs of surgical admission and 30-day readmissions

Abstract

Although surgical site infection (SSI) prevention bundles for hysterectomy are becoming standard at many institutions to improve patient care and experience, there are scant data available about how SSI prevention bundles affect cost of care. This study aimed to evaluate the effect of an SSI prevention bundle initiated at our institution on costs of initial surgical admission and subsequent re-admission for SSI-related causes. Data on hysterectomies performed from April 1, 2013, to December 31, 2015, were prospectively collected. There were 1303 cases in the 20-month period prior to full bundle implementation (April 1, 2013 to November 30, 2014) and 703 cases in the 13-month post-full bundle implementation period (December 1, 2014 to December 31, 2015). We used ICD-9/10 diagnosis codes to determine causes of readmissions within 30 days of hysterectomy, and focused on readmissions related to SSI. Total costs of care during hysterectomy hospitalization and SSI-related readmissions were obtained from our institution’s financial database, and included hospital facility costs of operating room supplies, laboratory fees, imaging, medications, room and board, and nursing care. All costs are reported in inflation adjusted 2015 US dollars. Patients’ clinical characteristics were collected via medical record review. Wilcoxon rank-sum tests and generalized linear regression analysis were used to compare costs in the pre- and post-full bundle implementation periods. Costs of hysterectomy hospitalization were significantly higher in the post-full bundle implementation period than in the pre-full bundle implementation period ($5,513 vs. $4,919, p < 0.001). When stratified by route of hysterectomy and presence or absence of gynecologic cancer, there was a statistically significant increase in cost of hysterectomy between the pre-full bundle and post-full bundle intervention periods for all routes except straight-stick laparoscopies for benign indications. The costs of hysterectomy admissions in pre-full bundle compared to post-full bundle implementation periods were, for benign disease: total abdominal hysterectomy (TAH): $4,801 versus $5,173 (p = 0.005), total laparoscopic hysterectomy (TLH): $4,186 versus $4,314 (p = 0.61), and robot-assisted total laparoscopic hysterectomy (raTLH): $4,666 versus $5,027 (p = 0.02). For malignancy: TAH: $6,602 versus $9,407 (p < 0.001), TLH: $4,408 versus $6,671 (p = 0.002), and raTLH: $4,469 versus $6,107 (p < 0.001). Multivariable regression analysis adjusting for patient age, comorbid conditions, BMI, and surgical route also suggested higher cost of hysterectomy hospitalizations during the period after full bundle implementation (adjusted cost ratio = 1.11, p < 0.001). The median cost of SSI-related hospital re-admissions were $3,527 pre-full bundle and $3,797 post-full bundle implementation (p = 0.65). The mean cost of all SSI related re-admissions was $5,795 ± 1,903. In our institution’s experience, SSI prevention bundles did not reduce hospital costs of surgical admissions over time, despite a significant decrease in SSI rate during the study period. Although there are cost savings in preventing readmission, there may be increasing hospital costs, particularly for open and robot-assisted laparoscopic cases, that warrant further assessment.