More than 300,000 patients are diagnosed with a surgical site infection (SSI) each year in the United States (Ban et al., 2017). SSI is defined by the World Health Organization (2016), as an infection in the body stemming from where the surgery was performed. SSI occurs when the surgical wound becomes infected after surgery and is a common cause of hospital readmissions following surgery (Agency for Healthcare Research and Quality, 2019). According to the Centers for Disease Control and Prevention (2019), the time frame for an SSI to occur is within 30 days after the surgery, or within 90 days if implants were used during the procedure. Risk factors for SSI include advanced age, tobacco use, diabetes, malnutrition, and a contaminated surgical wound. It is estimated that 3% of all patients who develop an infection after surgery will die as a result of complications stemming from the infection (Agency for Healthcare Research and Quality, 2019). However, most SSIs are preventable, and research supports the use of topical skin antiseptics to aid in the prevention of SSI when applied to the patient’s skin before the surgical incision is made (Dumville et al., 2015). The most commonly used skin antiseptics used in practice in the United States are chlorhexidine and povidone-iodine. While several studies have established the efficacy of both chlorhexidine and povidone-iodine in preventing SSIs, there is insufficient high-quality evidence to determine which antiseptic solution is more effective in preventing SSI, thus indicating a need for further research (Dumville et al., 2015).There is a need to examine the evidence to compare the use of chlorhexidine and povidone-iodine for preoperative skin antisepsis to determine which solution is associated with a lower rate of SSI and is more relevant to current clinical practice. The PICOT model was used as a framework to find the best available scientific evidence to answer the following focused clinical question: In adult patients undergoing surgery (P), is chlorhexidine (I) compared with povidone-iodine (C) more effective in preventing surgical site infections (O) within 30 days after surgery (T)? Database Search ProcessSelection Criteria Studies were selected from primary sources of information including credible, scholarly, peer-reviewed journals. The population, purpose, design, interventions, and findings of the individual studies were clearly stated and well-defined. The study design selected for the search were systematic reviews with meta-analysis of randomized controlled trials (RCT’s) because they provide the highest level of evidence regarding the effectiveness of treatment interventions (Polit & Beck, 2017). To be eligible for inclusion, all components of the PICOT question had to be specifically addressed. There had to be a detailed comparison of chlorhexidine and povidone-iodine for efficiency in preventing SSI on adult patients undergoing surgery, with specific outcomes measured for SSI occurrence within 30 days. Studies excluded from the review were studies involving children, studies involving patients with current wound infections, and studies older than 10 years. Search ProcessA comprehensive literature search from an online scientific database was used to conduct the search to find relevant articles. Medical Subject Headings (MeSH) terms and keywords that matched variables from the PICOT question were used to direct the search for locating the best available evidence to answer the focused clinical question. Electronic databases used for the search were PubMed (National Library of Medicine) and the Cumulative Index for Nursing and Allied Health Literature (CINAHL). The time frame for the search was between May and June 2019. MeSH terms used in the search were “chlorhexidine OR surgical site infections” “povidone-iodine OR SSI” and “postoperative wound infection.” The language was limited to English. The electronic database on PubMed yielded 186 articles. After MeSH terms were applied, findings were reduced to 105 articles. Additional limiters used to narrow the search results were age (adult population), studies done on humans, and publication dates (10 years or less) which narrowed findings to 44 articles. The study design was limited to (systematic reviews) which narrowed the findings to 19 articles. The CINAHL database displayed a total of 72 articles using key terms: SSI prevention AND chlorhexidine AND povidone-iodine. To narrow the search further, publication dates were limited to (10 years or less) which returned a total of 61 articles. Selecting academic journals further reduced the search results to 45 articles, and age (adult patients) narrowed the search results to 17 articles. Geography was limited to the United States and full-text articles were selected to yield a total of 10 articles. Inclusion and exclusion criteria were unique to each of the studies; however, some studies were not relevant and had to be excluded from the list of applicable findings. Selection of Best Evidence The studies obtained from the search were carefully examined to ensure they were a source of best evidence and were relevant to the variables of interest in the PICOT question: adult patients undergoing surgery (population), chlorhexidine and povidone-iodine (independent variables) for SSI prevention (dependent/outcome variable) within 30 days (timeframe). As previously stated, systematic reviews were targeted because they combine the highest level of evidence about a focused clinical question (Polit & Beck, 2017). Study design, methods, interventions, limitations, and outcomes were examined for credibility and to determine whether the variables matched those in the PICOT question. The individual studies were carefully screened for validity and reliability and each study had to provide an adequate analysis of the data with appropriate methods of analysis. Studies lacking a carefully planned design, studies that failed to address limitations, and studies not relevant to the variables of interest in the PICOT question were excluded as a source of best evidence. The study by Rodrigues (2013), analyzing the effectiveness of chlorhexidine and povidone-iodine use and the incidence of SSI was excluded as a source of best evidence because the study occurred in Brazil and it was not a systematic review or a level I source of evidence. Please see the Evaluation Matrix in Appendix A for additional study information. Critical Appraisal of Collective Evidence Two level I studies (systematic reviews with meta-analysis of RCT’s) and one level III study (systematic review with meta-analysis of well-designed RCT’s and observational studies) were examined for quality and to determine the generalizability of findings for clinical practice. While the researcher has no control over the independent variable in an observational study, they are valuable for showing correlations between the independent variable and the outcome variable of interest and in instances when it would be unethical to conduct a RCT (Melnyk & Fineout-Overholt, 2019). Critical Appraisal The purpose of the systematic review and meta-analysis of six randomized control trials by (Ayoub, Quirke, Conroy, & Hill, 2015), was to evaluate if chlorhexidine was more effective than povidone-iodine for the prevention of SSI. In three of the RCT groups, the participants were randomly assigned to groups, but the randomization methods for the participants in the remaining three groups were not specified. The methods used for the literature search were established by a knowledgeable health librarian and a medical researcher. The researchers examined the studies by hand to assess any reviews that may have been omitted in the electronic search (Ayoub et al., 2015). The studies were assessed for bias using the Cochrane risk of bias tool for the domains of randomization, allocation concealment, blinding and data completion and classified according to the level of risk as “low, unclear or high.” The risk of bias for performance, blinding of the participants and staff was specified as “unclear” for six of the studies (Ayoub et al., 2015). According to Polit & Beck (2017), blinding is not always feasible or ethical for certain types of interventions. For instance, in surgery, the interventionist (OR nurse), and the surgeon would certainly know whether or not chlorhexidine or povidone-iodine antiseptic was used to prep the patient’s skin. The Chi-Square test was used to assess for heterogeneity. Individual results were expressed to include relative risk, odds ratio, mean differences between groups, and were displayed in the form of a forest plot (Ayoub et al., 2015). The study revealed that chlorhexidine was more effective than povidone-iodine for the prevention of SSI in both clean and clean-contaminated surgery (Ayoub et al., 2015). Please refer to Appendix B for individual critiques of the selected studies.The objective of the systematic review and meta-analysis of nine RCT’s by (Lee, Agarwal, Lee, Fishman, & Umscheid, 2010), was to compare chlorhexidine and povidone-iodine for effectiveness in preventing SSI and to determine which antiseptic resulted in greater savings by performing a cost analysis of both skin antiseptics. The design and methods that were used for the study were appropriate and the audience was able to draw cause and effect relationships between the variables being studied. The I-2 test was used to measure heterogeneity. Funnel plots, weighted regression and rank correlation were used to assess publication bias for each of the studies (Lee et al., 2010). The Jadad and Chalmers scales were used to assess the studies for quality regarding randomization, blinding and participant attrition, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) scale was used to evaluate the quality of studies for the outcomes of SSI and positive skin culture (Lee et al., 2010). One potential bias that could have influenced the outcome of the study was selection bias. Only a single reviewer screened the potential articles for inclusion and the authors did not specify whether the search strategy was verified by a health librarian (Lee et al., 2010). The meta-analysis revealed that chlorhexidine antisepsis resulted in significantly fewer SSIs and positive skin cultures than povidone-iodine and reflected a net cost savings of $16 to $26 per surgery (Lee et al., 2010). Study findings were generalizable to adult patients undergoing surgery and the data obtained from the research provided sufficient evidence to make a valid comparison with the variables presented in the PICOT question.The purpose of the systematic review and meta-analysis (thirteen RCT’s and six observational studies) by Privitera et al., (2017) was to determine if chlorhexidine was more effective than povidone-iodine for SSI prevention. Only studies published between 2000 to 2014 were included in the review to ensure current clinical practice was reflected (Privitera et al., 2017). Limitations included the use of observational studies because they do not test if the intervention caused changes in the dependent variable (Polit & Beck, 2017). Additionally, the randomization methods used for the thirteen RCT’s were not provided. (Privitera et al., 2017). The GRADE scale was used to assess the quality of evidence for inconsistency, indirectness, imprecision and publication bias. The researchers subtracted one point for study quality and one point was added due to the large effect size (Privitera et al., 2017). One concern revealed in the study regarding chlorhexidine use is the potential for vestibular and ototoxicity. Corneal damage and hearing loss can occur if chlorhexidine is accidentally introduced into the ears or eyes during routine skin prepping. This risk can be significantly reduced by avoiding chlorhexidine use near the eyes, ears, or on children younger than two months of age (Fuller, 2017). SSI occurrence was measured in twelve of the thirteen RCT’s and in six of the observational studies. The meta-analysis revealed a 30% decrease in the occurrence of SSI for patients scrubbed with chlorhexidine, compared to patients scrubbed with povidone-iodine (Privitera et al., 2017). The findings are applicable to clinical practice for adult patients undergoing surgery excluding patients undergoing procedures involving the head due to the risk of corneal damage and vestibular toxicity.Collective ResultsSSI incidence was the primary outcome for all studies in this review. The effectiveness of skin antiseptics can be measured by SSI incidence. As previously stated, the timeframe for SSI incidence is within 30 days after surgery if prosthetics were not implanted. In the systematic review with meta-analysis by Ayoub et al., (2015), the overall rate of SSI for the chlorhexidine group was 6.8% versus 11% for the povidone-iodine group (95% CI, 0.48 to 0.81, p=0.0002, six studies, 2,484 participants). In the systematic review with the meta-analysis by Lee et al., (2010), the use of chlorhexidine for skin asepsis resulted in a 56% decrease in positive skin cultures in comparison to povidone-iodine, and significantly fewer SSIs than povidone-iodine (95% CI, 0.51 to 0.80, p=0.0001, nine studies, 3,614 participants). In the systematic review with meta-analysis of RCT’s and observational studies by Privitera et al., (2017), chlorhexidine resulted in a 30% decrease in SSIs and was favored over povidone-iodine for both SSI incidence (0.70 RR, 95% CI, 0.52 to 0.92) and bacterial skin colonization (0.45 RR, 95% CI, 0.36 to 0.55, nineteen studies, 3,437 participants). The overall analysis of all three studies revealed moderate-quality evidence supporting chlorhexidine use over povidone-iodine for skin asepsis and the prevention of SSI. Intervention DecisionThe results of all studies were homogeneous reporting significantly fewer SSIs associated with chlorhexidine than povidone-iodine. Based on the appraised studies, there is sufficient evidence to recommend a change in practice for standard preoperative skin asepsis. The effectiveness of chlorhexidine in decreasing SSI in adult patients undergoing surgery is supported by the best available evidence. Evidence-based recommendations include the use of a preoperative scrub and prep with chlorhexidine solution to be applied immediately before the incision is made on adult patients undergoing surgery.Plan for ImplementationThe John Hopkins Nursing Evidence-Based Practice Model (JHNEBP), is an appropriate framework for implementing chlorhexidine use into practice to aid in the prevention of SSI (inquiry/problem), in adult patients undergoing surgery (population). The JHNEBP model consists of three phases known as PET: practice question, evidence, and translation to solve problems and integrate evidence-based treatments and recommendations into care (Melnyk & Fineout-Overholt, 2019). During the practice question phase, the advanced practice nurse recruits a team to identify, develop and refine an answerable clinical question. In the evidence phase, a systematic search for scientific literature is conducted and each piece of evidence is meticulously appraised for overall strength and quality (Melnyk & Fineout-Overholt, 2019). After the evidence has been carefully synthesized, recommendations for practice change are made. Lastly, in the translation phase, an appropriate and feasible plan is devised to implement the new recommendations into practice (Melnyk & Fineout-Overholt, 2019). A non-experimental research design would be used to effectively address the intervention as patients would not be randomly assigned. Good communication about best practices is essential to disseminate the evidence and effectively translate the intervention into practice (Polit & Beck, 2017). Research findings regarding chlorhexidine use will be disseminated with surgeons, administration, and staff to inspire the implementation of the proposed intervention. After approval is granted for the proposed change, SSI rates would be assessed every 30 days to verify the chlorhexidine intervention was effective. Some of the staff may be reluctant to change current practice if they believe the chlorhexidine intervention would not make a difference in SSI prevention. However, emphasizing the importance of the research findings and involving staff and patients in the change process by consulting them about their values, preferences, and concerns will help to encourage motivation and engagement through the transition process.Conclusion A PICOT question was devised to direct the search for locating the best available evidence to answer a focused clinical question in determining if chlorhexidine is more effective than povidone-iodine in preventing SSI. All components of the PICOT question were addressed in this paper: The population (adult patients undergoing surgery), the intervention (chlorhexidine), the comparator (povidone-iodine), the outcome (SSI prevention), and the time frame (within 30 days). The evidence generated from this review supports the use of chlorhexidine over povidone-iodine for SSI prevention and results in greater cost savings and improved patient outcomes making it advantageous for integration into patient care. As healthcare professionals strive to implement new evidence-based practices they must carefully consider the needs of the patient when selecting a surgical skin antiseptic as they are extremely diverse.