To the Editor—We read “Implementation Strategies to Reduce Surgical Site Infections: A Systematic Review”Reference Ariyo, Zayed and Riese ¹ by Ariyo et al with great interest. Identifying ways to improve implementation and uptake of infection prevention interventions is critical as the field moves toward translating and implementing evidence-based findings into day-to-day clinical practice.

A key finding of the systematic review by Ariyo et al was that few high-quality trials have examined different implementation strategies in infection prevention. Adding to the limitations of the current literature identified in the outstanding review, some of our recent work across multiple procedural and surgical specialties highlights the challenges in bringing infection prevention practices to the bedside and operating room. In particular, we found that implementation of prevention practices is unevenly applied across the spectrum of care. This variation in effective implementation may lead to significant bias and confounding that impacts the apparent benefits of different infection prevention interventions.

A consistent finding across multiple specialties and clinical care areas has been that more stable patients receive more systematic, protocolized care. Processes of care are standardized and systematically applied to the stable, elective patient population. However, that is not true for more urgent or emergent cases, which tend to be identified for surgical procedures in inpatient settings. This inherently sicker and higher-risk population may be less predictable and more difficult to track and control, with environmental barriers to implementation that do not exist for the outpatient population.

We have identified these findings across different types of invasive procedures and using different methodologies. For example, during qualitative interviews with frontline electrophysiologists, we learned that,

This was also true for patients undergoing cardiac surgery in the STOP SSI study (cited by Ariyo et al)Reference Schweizer, Chiang and Septimus ² and similar subsequent unpublished studies. In the STOP SSI study, the significant reduction in complex S. aureus SSIs was only seen among orthopedic surgery patients but not cardiac surgery patients. The orthopedic surgery patients tended to be scheduled for elective surgery and had outpatient preoperative clinic visits in the 30 days prior to surgery. During this visit, the orthopedic patients were provided chlorhexidine body wash, were screened for S. aureus colonization and, if positive, were provided with a 5-day supply of mupirocin nasal ointment. In contrast, the cardiac surgery patients did not have a standardized outpatient preoperative clinic appointment and were often only seen in the inpatient setting.

Similarly, only 1.6% of patients undergoing urgent/emergent operations were fully adherent to the STOP SSI bundle, 40% of patients undergoing scheduled operations were fully adherent. This factor was reflected in the outcomes, in which there was only a statistically significant reduction in complex S. aureus SSIs among the scheduled operations and not the urgent/emergent operations. In a similar study performed in Veterans Affairs (VA) hospitals, a cardiac case manager from a small VA hospital stated:

Many infection prevention interventions, such as chlorhexidine washes and MRSA nasal screening and decolonization, require significant upfront investment of time and resources. Thus, providing these services to less stable patients and to add-on patients is difficult, if not impossible. Environmental barriers do not allow for showering and time restrictions do not allow for MRSA screening and multiple-day decolonization regimens.

These implementation challenges are critical areas of future research. First, as a field, we need better ways to implement infection prevention interventions and to track which patients receive them and which do not. In addition to healthcare-associated infection outcomes, consideration of intermediate, implementation outcomes (eg, adherence to the intervention), should be included in assessments of efficacy and effectiveness, so that the potential for confounding by indication can be assessed and addressed. Second, we need to find better ways to triage infection prevention strategies. Under the current system, the most aggressive care is being targeted to the lowest-risk patients. Infection prevention interventions that can be rapidly implemented in the day-of-surgery area or the operating room could be more effective than interventions that need to be started multiple days before surgery. More research is needed to determine how we can improve implementation and overcome barriers for the most vulnerable patients, rather than targeting care where it is most convenient to do so.