Unbundling Bundles: Evaluating the Association of Individual Colorectal Surgical Site Infection Reduction Bundle Elements on Infection Rates in a Statewide Collaborative

Abstract

BACKGROUND: Surgical site infection reduction bundles are effective but can be complex and resource intensive. Understanding which bundle elements are associated with reduced surgical site infections may guide concise bundle implementation.

OBJECTIVE: To evaluate the association of individual surgical site infection reduction bundle elements with infection rates.

DESIGN: Post-hoc analysis of a prospective cohort study

SETTING: Illinois Surgical Quality Improvement Collaborative hospitals

PATIENTS: Elective colorectal resections at participating hospitals from 2016–2017

INTERVENTIONS: 16-element colorectal surgical site infection reduction bundle

MAIN OUTCOME MEASURES: Surgical site infection rates were compared among patients by adherence with each bundle element using Chi-squared tests and multivariable logistic regression. Principal component analysis identified composites of correlated bundle elements. Coincidence analysis identified combinations of bundle elements or principal component composites associated with the absence of surgical site infection.

RESULTS: Among 2,722 patients, 192 (7.1%) developed a surgical site infection. Infections were less likely when oral antibiotics (OR 0.63 [95% CI 0.41–0.97]), wound protectors (OR 0.55 [95% CI 0.37–0.81]), and occlusive dressings (OR 0.71 [95% CI 0.51–1.00]) were used. Bundle elements were reduced into 5 principal component composites. Adherence with the combination of (1) oral antibiotics, (2) wound protector, or (3) redosing intravenous antibiotic prophylaxis plus chlorhexidine-alcohol intraoperative skin preparation were associated with the absence of infection (consistency=0.94, coverage=0.96). Four of the five principal component composites in various combinations were associated with the absence of surgical site infection, while the composite consisting of occlusive dressing placement, postoperative dressing removal, and daily postoperative chlorhexidine incisional cleansing had no association with the outcome.

LIMITATIONS: The inclusion of hospitals engaged in quality improvement initiatives may limit the generalizability of these data.

CONCLUSION: Bundle elements had varying association with infection reduction. Implementation of colorectal surgical site infection reduction bundles should focus on the specific elements associated with low surgical site infections. See Video Abstract at http://links.lww.com/DCR/Bxxx.