Pragmatic randomized trial evaluating pre-operative aqueous antiseptic skin solution in open fractures (Aqueous-PREP): the feasibility of a cluster randomized crossover study.

Background: Preoperative antiseptic skin solutions are used prior to most surgical procedures; however, there is no definitive research comparing infection-related outcomes following use of the various solutions available to orthopedic trauma surgeons. The objective of this pilot study was to test the feasibility of a cluster randomized crossover trial that assesses the comparative effectiveness of a 10% povidone-iodine solution versus a 4% chlorhexidine gluconate solution for the management of open fractures.

Methods: Two orthopedic trauma centers participated in this pilot study. Each of these clinical sites was randomized to a starting solution (povidone-iodine solution or chlorhexidine gluconate) then subsequently crossed over to the other treatment after 2 months. During the 4-month enrollment phase, we assessed compliance, enrollment rates, participant follow-up, and accurate documentation of the primary clinical outcome. Feasibility outcomes included (1) the implementation of the interventions during a run-in period; (2) enrollment of participants during two 2-month enrollment phases; (3) application of the trial interventions as per the cluster randomization crossover scheme; (4) participant follow-up; and (5) accurate documentation of the primary outcome (surgical site infection). Feasibility outcomes were summarized using descriptive statistics reported as means (standard deviation) or medians (first quartile, third quartile) for continuous variables depending on their distribution and counts (percentage) for categorical variables. Corresponding 95% confidence intervals (CIs) were also reported.

Results: All five of the criteria for feasibility were met. During the run-in phase, all 18 of the eligible patients identified at the two clinical sites received the correct cluster-assigned treatment. A total of 135 patients were enrolled across both sites during the 4-month recruitment phase, which equates to 92% (95% CI 85.9 to 96.4%) of eligible patients being enrolled. Compliance with the assigned treatment in the pilot study was 98% (95% CI 93.5 to 99.8%). Ninety-eight percent (95% CI 93.5 to 99.8%) of participants completed the 90-day post-surgery follow-up and the primary outcome (SSI) was accurately documented for 100% (95% CI 96.6 to 100.0%) of the participants.

Conclusions: These results confirm the feasibility of a definitive study comparing antiseptic solutions using a cluster randomized crossover trial design. Building upon the infrastructure established during the pilot phase, a definitive study has been successfully initiated.

Trial Registration: ClincialTrials.gov , number NCT03385304 . Registered December 28, 2017.