Examining SSI Prevention Measures According to the Evidence

With greater emphasis on translational research and evidence-based practices than ever before, there are interventions that seem to work better than others, although there is a wide margin for debate among experts. For example, Uçkay, et al. (2010) say that the pathogenesis of surgical site infections remains unresolved, with some studies exploring transmission from surgeons' hands to the surgical wound during surgery, while others indicate transmission during post-operative care, and still others point to infections originating from the patient versus those transmitted by the surgical staff, operating theater procedure or the environment.

Until further research can definitively pinpoint pathogenesis, it is imperative that clinicians engage in evidence-based preventive measures. Uçkay, et al. (2010) assert that four preventive measures are considered as having a high level of evidence (grade IA) according to the Centers for Disease Control and Prevention (CDC)'s Guideline for Prevention of Surgical Site Infection  (Mangram, et al., 1999): surgical hand preparation, appropriate antibiotic prophylaxis, and postponing of an elective operation in the case of active remote infection. Uçkay, et al. (2010) note that although hair clipping before surgery was considered grade IA evidence in the 1999 CDC guidelines, this high grading is now a matter of debate.

1. Surgical hand preparation:  As Uçkay, et al. (2010) explain, "Its importance is supported by expert opinion, experimental studies and success stories of SSI reduction via mere hand hygiene promotion campaigns. However, owing to their multimodal design, most hand hygiene campaigns cannot distinguish between SSI reduction due to improved antisepsis in the operating theater versus better patient and wound care on the ward."

2. Antibiotic prophylaxis: Uçkay, et al. (2010)  emphasize that successful prophylactic antibiotic use depends on a number of key factors including the patient's history of allergy; the proportional distribution of pathogens and prevalence within the hospital; the correct dosage; and timely administration.

3. Postponing elective surgery in the case of symptomatic remote infection: Uçkay, et al. (2010) note that, "This issue is regarded as high evidence in the CDC guidelines, although there are no randomized trials on the topic of postponing to the best of our knowledge."

Other interventions considered to have high levels of efficacy, according to Uçkay, et al. (2010) include expertise of the surgeon and adherence to aseptic techniques; active surveillance of SSI rates with feedback; and multi-modal intervention. As Uçkay, et al. (2010) explain, "Instead of targeting single risk factors, it is advised to target several at the same time, although they are usually based on pre-post intervention studies and not randomized trials or meta-analyses. Multimodal interventions, sometimes in the form of so-called 'bundles' have become very popular in recent years. A variant are safety checklists that have been inspired from the airline industry ... Multimodal interventions based on bundles or checklists are the strategy with the highest impact in terms of SSI prevention."

Some interventions hold great promise for the prevention of SSIs and warrant further research and development, according to Uçkay, et al. (2010); these include screening for MRSA carriage on admission; screening for nasal Staph aureus colonization and subsequent decolonization; avoidance of intraoperative hypothermia; avoidance of intraoperative hyperglycemia; and administration of supplemental oxygen intraoperatively. Some other measures that show promise but still need to be confirmed in additional randomized trials, according to Uçkay, et al. (2010) include naso- and oropharynx decontamination with chlorhexidine before surgery; continuous, positive airway pressure during anesthesia to avoid post-operative hypoxemia; and whether minimal invasive surgery or the use of laparoscopy versus laparotomy may lower SSI risk.

There will always be interventions that trigger lively discussion among experts as the evidence evolves. As Uçkay, et al. (2010) acknowledge, "Some measures used in daily practice are profoundly embedded in our medical culture, but nevertheless lack evidence as to their real efficacy. Substantial new evidence is needed to upgrade these recommendations." These include, according to Uçkay, et al. (2010): preoperative bathing/showering; preoperative skin preparation; gloves and adhesive drapes; preoperative hair removal; laminar airflow in the operating room; use of staples versus sutures; use of drains; microbial sealing to reduce wound contamination; and post-surgical wound care.

References:

Mangram AJ, Horan TC, Pearson ML, Silver LC, Jarvis WR. Guideline for prevention of surgical site infection, 1999. Hospital Infection Control Practices Advisory Committee. Infect. Control Hosp. Epidemiol. 20, 250-278. 1999.
 
Uçkay I, Harbarth S, Peter R, Lew D, Hoffmeyer P, and Pittet D. Preventing Surgical Site Infections. Expert Rev Anti Infect Ther. 2010;8(6):657-670.