Background: Adequate skin preparation is essential to preventing surgical site infection. Many products are available, each with specific manufacturers' directions. This lack of standardization may lead to incorrect use of the agents and affect the bacterial load reduction. We hypothesize that a lack of adherence to utilization protocols for surgical skin antiseptics affects bacterial load reduction.
Methods: Thirty subjects who routinely perform surgical skin preparation were recruited from four hospitals. Participants completed a questionnaire of both demographics and familiarity with two of the most common skin prep formulas: Chlorhexidine gluconate-isopropyl alcohol (CHG-IPA) and povidone-iodine (PVI) scrub and paint. Randomly selecting one formula, subjects performed skin preparation for ankle surgery on a healthy standardized patient. This was repeated using the second formula on the opposite ankle. Performance was recorded and reviewed by two independent evaluators using standardized dichotomous checklists created against the manufacturer's recommended application. Swabs of the patients' first interweb space and medial malleolus were obtained before, 1 min after, and 30 min after prep, and plated on Luria Bertani agar. Bacterial loads were measured in colony forming units (CFUs) for each anatomical site. Data was analyzed using a univariate linear regression.
Results: Subjects had an average of 12.7 ± 2.2 y operating room experience and 8.8 ± 1.5 y of skin prep experience. Despite this, no participant performed 100% of the manufacturers' steps correctly. All essential formula-specific steps were performed 90% of the time for CHG-IPA and 33.3% for PVI (p = 0.0001). No correlation was found between experience or familiarity and number of correct steps for either formula. Average reduction in CFUs was not different between CHG-IPA and PVI at 30 min for all anatomical sites (75.2 ± 5.4% vs. 73.7 ± 4.5%, p = 0.7662). Bacterial reductions at 30 min following skin prep were not substantially correlated with operator experience, protocol compliance, or total prep time for either formula.
Conclusion: This study demonstrates existing problems with infection prevention as those tasked with pre-operative skin preparation do so with tremendous incongruence according to manufacturer guidelines. No effect on bacterial load was identified, however with a larger sample size this may be noted. Standardization of the prep solutions as well as simplification and education of the correct techniques may enhance protocol compliance.