Retrospective analysis of the Photo at Discharge scheme and readmission for surgical site infection following coronary artery bypass graft surgery

Background: Surgical site infection (SSI) is a costly and devastating complication of surgery. Many cardiac SSIs develop after the patient leaves hospital, but evidence demonstrating the benefit of patient/carer involvement in the process of monitoring and promptly identifying SSI post-discharge is limited. This study estimates the probability of readmission for SSI for coronary artery bypass graft (CABG) patients receiving the Photo at Discharge (PaD).

Methods: Trained personnel undertook continuous, prospective SSI surveillance using Public Health England protocol between January 2013 and December 2016. Baseline covariables were collected for 1747 CABG-only procedures. As a quasi-randomised design, we adjusted for non-random PaD assignment using retrospective propensity score (PS)-matching based on 12 variables of interest, assessed whether the model had been adequately specified and performed an outcomes analysis.

Results: A total of 568 patients with PaD were PS-matched with 568 controls. The probabilities of SSI readmission were 0.352 (2/568) and 1.761 (10/568), respectively. The difference in risk of readmission for SSI was significant (relative risk = 0.2, 95% confidence interval = 0.04-0.91; P = 0.04).

Conclusion: Findings from this single-centre observation study suggest the PaD is associated with a reduction in CABG readmission for SSI and a further study is warranted to verify the efficacy of this strategy.