Prophylactic antibiotics in groin hernioplasty: a prospective cohort study on the prevention of surgical site infection

Prophylactic antibiotics in groin hernioplasty: a prospective cohort study on the prevention of surgical site infection | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Prophylactic antibiotics in groin hernioplasty: a prospective cohort study on the prevention of surgical site infection Waleed Mohammed Gilan, Loai Mohammed Al-Qubati, Yasser Abdurabo Obadiel, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7054933/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: The role of prophylactic antibiotics in preventing surgical site infections (SSI) in clean procedures such as groin hernioplastyremains controversial. This study aimed to evaluate the association between antibiotic prophylaxis and SSI rates in a real-world setting and identify independent risk factors for SSI. Methods: This single-center, prospective cohort study was conducted at Al-Gumhori Teaching Hospital, Sana'a, Yemen. A total of 100 male patients undergoing elective open groin hernioplasty were prospectively followed. Patients were categorized into two groups based on the treating surgeon's decision: those who received a single dose of intravenous cefazolin (Antibiotic Group, n=50), and those who did not receive antibiotic prophylaxis (No Antibiotic Group, n=50). The primary outcome was the incidence of SSI within 30 days. Univariate and multivariate logistic regression analyses were performed to identify the risk factors for SSI. Results: The SSI rate was 6.0% in the antibiotic group and 14.0% in the non-antibiotic group (overall rate 10.0%), respectively (p = 0.318). Multivariate logistic regression analysis identified high BMI (Adjusted OR 17.93, p = 0.041) and prolonged operative time >60 min (Adjusted OR 72.15, p = 0.010) as the only significant independent predictors of SSI. Antibiotic prophylaxis showed a strong but not statistically significant protective trend after adjusting for other factors (Adjusted OR odds ratio [OR], 0.15; 95% confidence interval [CI], 0.018–1.28; p = 0.076). Conclusion: Routine prophylactic antibiotic administration was not significantly associated with a reduction in the SSI rates. A high BMI and prolonged operative time are key drivers of infection risk, supporting a risk-stratified approach in which prophylaxis is targeted to high-risk patients. Clinical trial number: not applicable. hernioplasty surgical site infection antibiotic prophylaxis groin hernia wound infection Figures Figure 1 Figure 2 INTRODUCTION Groin hernia repair is one of the most commonly performed surgical procedures worldwide, with mesh-based techniques established as the standard of care because of their reduced recurrence rates[ 1 ]. Despite being classified as a clean surgical procedure, surgical site infection (SSI) remains a significant complication, imposing a substantial clinical and economic burden[ 2 ]. The high global volume of this procedure underscores the importance of effective evidence-based SSI prevention. The routine use of prophylactic antibiotics in clean hernia repair remains a subject of considerable debate fueled by inconsistent evidence and conflicting clinical guidelines. Several high-quality systematic reviews and meta-analyses have reported that antibiotic prophylaxis can significantly reduce the risk of SSI. Landmark reviews by Al Riyees et al. and Sánchez-Manuel et al., along with a network meta-analysis by Boonchan et al., collectively demonstrate a protective effect, particularly in the context of mesh-based repairs where the presence of a foreign body increases infection risk[ 3 – 5 ]. A randomized controlled trial by Mazaki et al. reported a dramatic reduction in SSI from 13% in the placebo group to only 2% in the cefazolin group, highlighting the potential benefit in specific settings[ 6 ]. However, this evidence is balanced by a strong counternarrative questioning of the necessity of universal prophylaxis. A comprehensive Cochrane review by Orelio et al. concluded that while a modest benefit exists, it is most apparent in high-risk environments, with little to no advantage in low-risk patient populations[ 7 ]. This finding was echoed in a meta-analysis by Erdas et al., who suggested that the statistical significance of the benefit disappeared after removing outlier studies from their analysis[ 8 ]. Several prospective trials have further solidified this view, finding no significant difference in SSI rates between antibiotic and placebo groups in low-risk cohorts undergoing elective repair[ 9 , 10 ]. This apparent contradiction in the literature suggests that the central issue is not whether antibiotics work but for whom they are necessary. The debate stems from a traditional ‘one-size-fits-all’ approach that fails to account for patient-specific risk factors, a limitation that modern evidence-based guidelines seek to address through structured, risk-stratified protocols[ 11 ]. Consequently, a paradigm shift toward this type of strategy is warranted, aligning with antimicrobial stewardship principles to avoid overuse and development of resistance[ 12 ]. Identifying patients with intrinsic risk factors is essential for prophylactic optimization. Factors such as obesity (high BMI) and prolonged operative time have been consistently identified as potential predictors of SSI in observational studies and systematic reviews[ 13 , 14 ]. However, their independent impact requires further validation through well-designed prospective studies to clarify their real-world associations. METHODS Study Design and Setting This single-center, prospective, observational cohort study was conducted at the Al-Gumhori Teaching Hospital, a tertiary care center in Sana'a, Yemen, from October 2023 to May 2024. This study aimed to evaluate the association between prophylactic antibiotics and the incidence of surgical site infections (SSI) following open groin hernioplasty. Participants Eligible participants were adult male patients (aged 17–80 years) scheduled for elective open groin hernioplasty. Exclusion criteria included recurrent hernias, emergency or complicated (e.g., incarcerated, strangulated) hernias, laparoscopic repairs, known immunosuppression, ongoing antibiotic therapy, a known allergy to cefazolin, or refusal to participate. Cohort Definition and Exposure Eligible patients who provided informed consent were enrolled prospectively. The decision to administer prophylactic antibiotics was left to the discretion of the surgical treatment team, reflecting real-world clinical practice. Based on this decision, the patients were categorized into two exposure groups for analysis. Antibiotic Group (exposed) : Patients who received a single intravenous dose of cefazolin (2 g) were administered 30–60 min prior to skin incision. No Antibiotic Group (unexposed) : patients who did not receive prophylactic antibiotics. All patients underwent standardized open groin hernioplasty with polypropylene mesh reinforcement performed by experienced surgeons. Outcomes and Data Collection The primary outcome was the incidence of SSI within 30 days postoperatively, as defined by the U.S.. Centers for Disease Control and Prevention (CDC) criteria[ 15 ]. Secondary outcomes included the identification of independent risk factors for SSI. Data were collected using a structured questionnaire covering demographic characteristics, medical history (comorbidities and smoking status), ASA of Anesthesiologists physical status score, and surgical details (operative duration). The patients were followed up via clinic visits at 7 and 30 days to assess signs of infection. Statistical Analysis The required sample size was estimated a priori. To detect a difference in SSI rates between the exposed and unexposed groups (assuming rates of 5% and 15%, respectively) with an alpha of 0.05 and 80% power, a minimum of 47 patients per group were required. To account for potential dropouts, 50 patients were enrolled in each group for the analysis. All statistical analyses were performed using SPSS Statistics, Version 26.0 (IBM Corp., Armonk, NY, USA). Statistical significance was set at a two-sided p-value of < 0.05. Baseline demographic and clinical characteristics were summarized using descriptive statistics and compared between the two exposure groups to assess potential confounding factors. Continuous variables are presented as mean ± standard deviation (SD) and were compared using independent t-tests or Mann–Whitney U tests. Categorical variables are presented as frequencies and percentages (n, %) and were compared using the chi-square test or Fisher’s exact test. The primary outcome, that is, the difference in SSI rates between the two groups, was analyzed using Fisher’s exact test. The results are expressed as odds ratios (OR) with 95% confidence intervals (CI). To identify the risk factors for SSI and adjust for potential confounding factors, both univariate and multivariate logistic regression analyses were performed. First, univariate models were constructed to assess the individual association of each potential risk factor (high BMI ≥ 30 kg/m ², high ASA score, prolonged operation time > 60 min, comorbidities, and smoking) with SSI development. Variables that were significant in the univariate analysis or deemed clinically important (including primary exposure to antibiotics) were then included in a multivariate logistic regression model to identify independent predictors and calculate the adjusted odds ratios (aORs). Finally, we conducted exploratory subgroup analyses to investigate the effects of antibiotics specifically in high-risk patient populations. Ethical Considerations This study was conducted in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Ethics Committee of the Faculty of Medicine and Health Sciences of Sana'a University, Sana'a, Yemen, and the Al-Gumhori Teaching Hospital. All participants provided written informed consent prior to enrollment. RESULTS Participant Characteristics One hundred male patients who underwent elective open groin hernioplasty were enrolled in this study. Fifty patients received prophylactic antibiotics (Antibiotic Group), and 50 did not (no-antibiotic group). The baseline demographic and clinical characteristics were compared between the two groups ( Table 1 ) . No statistically significant differences were observed in the measured baseline variables , suggesting that these specific factors were comparable between the two groups. The mean age of the cohort was 46.6 ± 17.0 years. Overall, 10% of the patients had a BMI ≥ 30 kg/m ², and 25% had an ASA score of 2. Table 1 Baseline Characteristics of Study Participants Characteristic Antibiotic Group (n = 50) No Antibiotic Group (n = 50) Total (n = 100) P-value Age (years), mean ± SD 45.8 ± 16.2 47.4 ± 17.8 46.6 ± 17.0 0.632 BMI ≥ 30 kg/m² 4 (8%) 6 (12%) 10 (10%) 0.508 Smoking 12 (24%) 15 (30%) 27 (27%) 0.512 Comorbidities 8 (16%) 13 (26%) 21 (21%) 0.243 ASA Score 2 11 (22%) 14 (28%) 25 (25%) 0.493 Operation Time (min), mean ± SD 56.2 ± 12.4 58.5 ± 14.2 57.4 ± 13.3 0.418 Notes : P-values were calculated using independent t-tests for continuous variables and Chi-square or Fisher’s exact tests for categorical variables. Abbreviations : SD, Standard Deviation; BMI, Body Mass Index; ASA, American Society of Anesthesiologists. Primary Outcome: Surgical Site Infection The overall incidence of surgical site infection (SSI) within 30 days was 10.0% (10/100). As detailed in Table 2 , the SSI rate in the Antibiotic Group was 6.0% compared with 14.0% in the no-antibiotic group. This absolute risk reduction of 8.0 percentage points did not reach statistical significance (p = 0.318). The odds of developing an SSI were lower in the antibiotic group, but the confidence interval was wide and crossed 1.0 (OR 0.39, 95% CI 0.095–1.613) (Fig. 1 ). Table 2 Surgical Site Infection Outcomes by Exposure Group Statistical Test Results Measure Antibiotic Group (n = 50) No Antibiotic Group (n = 50) Statistical Test SSI Cases 3/50 7/50 - SSI Rate (%) 6.0% 14.0% - Absolute Risk Reduction 8.0 percentage points - Odds Ratio 0.392 (95% CI: 0.095–1.613) - P-value 0.318 Fisher’s exact test Significance Not Signi fi cant (p > 0.05) α = 0.05 Note : The p-value was calculated using Fisher’s exact test. Abbreviations : SSI, Surgical Site Infection; CI, Confidence Interval. Risk Factor Analysis Univariate Analysis Univariate analysis of the entire cohort revealed that these three factors were significantly associated with an increased risk of SSI ( Table 3 ) . A high BMI (≥ 30 kg/m ²) was the strongest predictor (OR 17.00, p = 0.0007), followed by prolonged operation time (> 60 min) (OR 9.85, p = 0.0025) and a higher ASA score of 2 (OR 5.61, p = 0.0145). Table 3 Univariate Analysis of Risk Factors for Surgical Site Infection (N = 100) Risk Factor Odds Ratio (OR) 95% Confidence Interval (CI) P-value High BMI (≥ 30 kg/m²) 17.00 3.07–94.05 0.0007 Long Operation (> 60 min) 9.85 2.06–47.07 0.0025 High ASA Score (ASA 2) 5.61 1.19–26.48 0.0145 Comorbidities 2.17 0.54–8.75 0.397 Smoking 1.83 0.46–7.34 0.510 Notes : Results are from individual univariate logistic regression models for each risk factor. Significant p-values (< 0.05) are shown in bold font. Abbreviations : OR, Odds Ratio; CI, Confidence Interval; BMI, Body Mass Index; ASA, American Society of Anesthesiologists. Multivariate Analysis A multivariate logistic regression model was constructed to identify independent predictors of SSI (Table 4 ). After adjusting for all variables, high BMI (aOR 17.93, p = 0.041) and prolonged operation time (aOR 72.15, p = 0.010) remained significant independent risk factors. A high ASA score was no longer a significant predictor in the adjusted model (p = 0.862), suggesting that other factors confounded its effect. Administration of prophylactic antibiotics was associated with a strong protective trend (aOR 0.15), but this was not statistically significant (p = 0.076). These results are shown in the forest plots in Fig. 2 . Table 4 Multivariate Logistic Regression Analysis of Independent SSI Risk Factors Variable Adjusted Odds Ratio (aOR) 95% Confidence Interval (CI) P-value Antibiotic Prophylaxis (Yes vs. No) 0.15 0.018–1.28 0.076 High BMI (≥ 30 kg/m ²) 17.93 1.14–282.07 0.041 Long Operation (> 60 min) 72.15 2.78–1871.47 0.010 Comorbidities 13.93 0.78–248.80 0.077 High ASA Score (ASA 2) 1.23 0.12–12.55 0.862 The model simultaneously includes all listed variables. Significant p-values (< 0.05) are shown in bold font. Abbreviations: aOR, Adjusted Odds Ratio; CI, Confidence Interval; BMI, Body Mass Index; ASA, American Society of Anesthesiologists. Subgroup Analysis in Patients with High Risk Subgroup analysis was performed to explore the effect of antibiotics on high-risk patient populations identified in the risk factor analysis ( Table 5 ) . Table 5 Subgroup Analysis of Antibiotic Effectiveness in High-Risk Patients High-Risk Subgroup Antibiotic Group SSI Rate (n/N) No Antibiotic Group SSI Rate (n/N) Odds Ratio (95% CI) P-value High BMI (≥ 30 kg/m ²) 20.0% (1/5) 80.0% (4/5) 0.067 (0.003–1.378) 0.083 High ASA (ASA 2) 10.0% (1/10) 33.3% (5/15) 0.231 (0.023–2.354) 0.345 Note : P-values were calculated using Fisher’s exact test for each subgroup. Abbreviations : SSI, Surgical Site Infection; CI, Confidence Interval; BMI, Body Mass Index; ASA, American Society of Anesthesiologists. In patients with high BMI, prophylactic antibiotics were associated with a strong trend toward a protective effect, reducing the SSI rate from 80.0–20.0%. However, this finding was not statistically significant (p = 0.083), likely because of the small number of patients in this subgroup (n = 10). A moderately non-significant effect was also observed in patients with high ASA scores. DISCUSSION This prospective cohort study did not find a statistically significant association between routine prophylactic antibiotics and SSI rates in an unselected population of patients who underwent groin hernioplasty. The SSI rate was 6.0% in the antibiotic group versus 14.0% in the no-antibiotic group (p = 0.318), which supports a more selective prophylactic approach. The 8.0 percentage point absolute risk reduction that we observed, although not statistically significant, is directionally consistent with the modest benefits reported in major systematic reviews[ 3 ]. Our results contribute to the existing and important controversies. Foundational work, including Cochrane reviews by Sanchez-Manuel et al. and Orelio et al. (2020), has long questioned the value of universal prophylaxis, particularly in low-risk settings[ 5 , 7 ]. Recent evidence suggests that while antibiotics can be effective, the effect is context-dependent, with the greatest benefit observed in high-risk environments or mesh-based repairs[ 3 , 7 ]. Our study provides crucial primary data that reinforce this narrative: the overall benefit is not statistically robust in a mixed-risk real-world cohort. The most important findings of our study emerged from the multivariate analysis, which revealed that only a high BMI (> 30 kg/m ²) and prolonged operative time (> 60 min) were significant independent predictors of SSI. This analysis is critical in observational studies because it helps statistically adjust for baseline differences and isolate the impact of individual risk factors. Notably, the initially significant association with a high ASA score was attenuated after multivariate adjustment, indicating that it may serve as a proxy for other risk factors. This finding emphasizes the necessity of shifting from universal prophylaxis to a targeted risk-stratified approach. Our finding that obesity is a powerful independent predictor is strongly supported by literature. A systematic review by Quiroga-Centeno et al. (2022) confirmed this robust association in the repair of abdominal wall hernias, likely mediated by factors such as impaired wound healing and poor tissue perfusion[ 13 ]. Similarly, the link between prolonged operative time and increased SSI risk has been well established, as confirmed in a systematic review by Cheng et al. (2017)[ 14 ]. Clinically, these results provide strong evidence to support targeted antibiotic prophylaxis in high-risk patients. Our subgroup analysis, although limited by a small sample size, showed a substantial trend toward a protective benefit in patients with a high BMI who received antibiotics (SSI rate 20% vs. 80%; p = 0.083), indicating a clinically meaningful effect that warrants further investigation. This selective strategy aligns with the modern principles of antimicrobial stewardship[ 11 ]. This study has several limitations. First, its observational design means that we can only report associations and cannot establish causality. Although we performed a multivariate analysis to control for the measured variables, the risk of unmeasured confounding factors remained. For example, surgeons may have been more inclined to administer antibiotics to patients that they intuitively perceived as having a higher risk for reasons not captured in our data (confounding by indication). Third, this single-center, male-only cohort study limited the generalizability of our findings. Finally, the study's sample size was likely underpowered to detect a statistically significant difference in the primary outcome, particularly in subgroup analyses. CONCLUSION In conclusion, this prospective cohort study found that routine prophylactic antibiotic administration was not significantly associated with a reduced surgical site infection rate in an unselected population of patients undergoing groin hernioplasty. The most important independent risk factors for developing infection were high BMI (≥ 30 kg/m ²) and prolonged operative time (> 60 min). These findings strongly support a shift away from universal prophylaxis toward a selective, risk-stratified strategy in which antibiotics are targeted to patients with these specific risk factors to optimize outcomes and support antimicrobial stewardship. Larger randomized trials or multicenter cohort studies are needed in the future to confirm the benefits of this targeted approach and to inform the next generation of evidence-based clinical guidelines. Declarations Ethical Approval and Consent to Participate This study was conducted in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Ethics Committee of the Faculty of Medicine and Health Sciences of Sana'a University, Sana'a, Yemen, and the Al-Gumhori Teaching Hospital. All participants provided written informed consent prior to enrollment. Consent for Publication Not applicable. (This is used if your manuscript contains identifying patient information, such as photos or detailed case descriptions, which yours does not). Competing Interests The authors declare that they have no conflicts of interest. Funding This research received no specific grants from any funding agency in the public, commercial, or not-for-profit sector. Author Contribution WMG designed the study, collected data, and drafted the manuscript. LMA and YAO supervised the study and revised the manuscript critically. MMA and HMJ contributed to data analysis and manuscript review. All authors have read and approved the final version of the manuscript. Data Availability The data supporting the findings of this study are available from the corresponding author upon reasonable request. References HerniaSurge Group. International guidelines for groin hernia management. Hernia 2018;22:1–165. https://doi.org/10.1007/s10029-017-1668-x. Seidelman JL, Mantyh CR, Anderson DJ. Surgical Site Infection Prevention: A Review. JAMA 2023;329:244–52. https://doi.org/10.1001/jama.2022.24075. Al Riyees L, Al Madani W, Firwana N, Balkhy HH, Ferwana M, Alkhudhayri A. Antibiotic Prophylaxis against Surgical Site Infection after Open Hernia Surgery: A Systematic Review and Meta-Analysis. Eur Surg Res 2021;62:121–33. https://doi.org/10.1159/000517404. Boonchan T, Wilasrusmee C, McEvoy M, Attia J, Thakkinstian A. Network meta-analysis of antibiotic prophylaxis for prevention of surgical-site infection after groin hernia surgery. Br J Surg 2017;104:e106–17. https://doi.org/10.1002/bjs.10441. Sanchez-Manuel FJ, Lozano-García J, Seco-Gil JL. Antibiotic prophylaxis for hernia repair. Cochrane Database Syst Rev 2007:CD003769. https://doi.org/10.1002/14651858.CD003769.pub3. Mazaki T, Mado K, Masuda H, Shiono M, Tochikura N, Kaburagi M. A randomized trial of antibiotic prophylaxis for the prevention of surgical site infection after open mesh-plug hernia repair. Am J Surg 2014;207:476–84. https://doi.org/10.1016/j.amjsurg.2013.01.047. Orelio CC, van Hessen C, Sanchez-Manuel FJ, Aufenacker TJ, Scholten RJ. Antibiotic prophylaxis for prevention of postoperative wound infection in adults undergoing open elective inguinal or femoral hernia repair. Cochrane Database Syst Rev 2020;4:CD003769. https://doi.org/10.1002/14651858.CD003769.pub5. Erdas E, Medas F, Pisano G, Nicolosi A, Calò PG. Antibiotic prophylaxis for open mesh repair of groin hernia: systematic review and meta-analysis. Hernia 2016;20:765–76. https://doi.org/10.1007/S10029-016-1536-0. Razack A, Kapoor KK, Tambat RM. THE ROLE OF SINGLE DOSE ANTIBIOTIC PROPHYLAXIS IN OPEN MESH REPAIR OF INGUINAL HERNIA : A PROSPECTIVE, DOUBLE BLIND RANDOMIZED TRIAL. J Evol Med Dent Sci 2015;4:6017–26. https://doi.org/10.14260/JEMDS/2015/877. Singh V, Kumar M, Kumar A. EVALUATION OF THE ROLE OF PROPHYLACTIC ANTIBIOTIC VERSUS NO ANTIBIOTIC IN CASES OF GROIN HERNIA SURGERY. International Journal of Medical and Pharma Research 2015;4:37–40. Sartelli M, Coccolini F, Labricciosa FM, Al Omari AbdelKarimH, Bains L, Baraket O, et al. Surgical Antibiotic Prophylaxis: A Proposal for a Global Evidence-Based Bundle. Antibiotics 2024;13:100. https://doi.org/10.3390/antibiotics13010100. Klifto KM, Rydz AC, Biswas S, Hultman CS, Erdmann D, Phillips BT. Evidence-Based Medicine: Systemic Perioperative Antibiotic Prophylaxis for Prevention of Surgical-Site Infections in Plastic and Reconstructive Surgery. Plast Reconstr Surg 2023;152:1154E-1182E. https://doi.org/10.1097/PRS.0000000000010608. Quiroga-Centeno AC, Quiroga-Centeno CA, Guerrero-Macías S, Navas-Quintero O, Gómez-Ochoa SA. Systematic review and meta-analysis of risk factors for Mesh infection following Abdominal Wall Hernia Repair Surgery. Am J Surg 2022;224:239–46. https://doi.org/10.1016/j.amjsurg.2021.12.024. Cheng H, Chen BP-H, Soleas IM, Ferko NC, Cameron CG, Hinoul P. Prolonged Operative Duration Increases Risk of Surgical Site Infections: A Systematic Review. Surg Infect (Larchmt) 2017;18:722–35. https://doi.org/10.1089/sur.2017.089. Berriós-Torres SI, Umscheid CA, Bratzler DW, Leas B, Stone EC, Kelz RR, et al. Centers for Disease Control and Prevention Guideline for the Prevention of Surgical Site Infection, 2017. JAMA Surg 2017;152:784–91. https://doi.org/10.1001/JAMASURG.2017.0904. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7054933","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":488423354,"identity":"7124eda0-fd48-4c7d-a04c-17bc0bcde78f","order_by":0,"name":"Waleed Mohammed Gilan","email":"","orcid":"","institution":"Sana’a University","correspondingAuthor":false,"prefix":"","firstName":"Waleed","middleName":"Mohammed","lastName":"Gilan","suffix":""},{"id":488423355,"identity":"a4e87c6f-d824-49f1-b4e1-9518cd392566","order_by":1,"name":"Loai Mohammed Al-Qubati","email":"","orcid":"","institution":"Sana’a University","correspondingAuthor":false,"prefix":"","firstName":"Loai","middleName":"Mohammed","lastName":"Al-Qubati","suffix":""},{"id":488423356,"identity":"225ad609-5606-49b5-a2df-78e39e4c832a","order_by":2,"name":"Yasser Abdurabo Obadiel","email":"","orcid":"","institution":"Sana’a University","correspondingAuthor":false,"prefix":"","firstName":"Yasser","middleName":"Abdurabo","lastName":"Obadiel","suffix":""},{"id":488423357,"identity":"f0c9d2bc-3f73-4837-b597-d6cb34a39899","order_by":3,"name":"Mareb Museid Alward","email":"","orcid":"","institution":"Al-Gumhori Teaching Hospital","correspondingAuthor":false,"prefix":"","firstName":"Mareb","middleName":"Museid","lastName":"Alward","suffix":""},{"id":488423358,"identity":"fb07d29c-8e58-427e-a62e-0edea3857df7","order_by":4,"name":"Haitham Mohammed Jowah","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAzUlEQVRIiWNgGAWjYBACAwaGBCB1QA7M4yFFizFJWkDgQGID0VrMGRgePuapuZM+f0YC44O3bQyJ/YS0WDYwJBvzHHuWu+FGArPhXKCWmQ2EHHaAIU06h+1w7gaJBDZpXqCWDQeI0vLvcLr8jAT23yAt+4nSktt2OIHhRgIbM9gWQn4xOAz0y9++w4YbzjxslpxzTsJ4BkFbjvckPpzx7bC8fHvywQ9vymxk+xsIWcPMkwBlMYLUSjgS1MHAwI7qEHvCOkbBKBgFo2CkAQCEAUMIrb03fgAAAABJRU5ErkJggg==","orcid":"","institution":"Sana’a University","correspondingAuthor":true,"prefix":"","firstName":"Haitham","middleName":"Mohammed","lastName":"Jowah","suffix":""}],"badges":[],"createdAt":"2025-07-05 20:53:09","currentVersionCode":1,"declarations":{"humanSubjects":false,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-7054933/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7054933/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":87347595,"identity":"68c28f1f-8385-48d4-9c01-c27cc19bb9cd","added_by":"auto","created_at":"2025-07-23 02:39:37","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":39834,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSurgical Site Infection Rates by Exposure Group.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7054933/v1/fcd7b7c55f7e954679600a06.jpg"},{"id":87347596,"identity":"b3723197-5ddd-480f-9b78-2cf90fdae9fd","added_by":"auto","created_at":"2025-07-23 02:39:38","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":31639,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003e\u003cstrong\u003eForest plot of adjusted odds ratios (aORs) for SSI Risk Factors.\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e The plot displays the adjusted odds ratios (aORs) and 95% confidence intervals from the final logistic regression model. The vertical dashed line represents null effect (aOR = 1.0). High BMI and prolonged operation time were the only factors significantly associated with an increased risk of SSI as their confidence intervals did not cross the null line (p \u0026lt; 0.05).\u003c/em\u003e\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7054933/v1/ab26ba028d1c84602633d89f.jpg"},{"id":90641850,"identity":"6cf6301b-e6a8-47c4-b647-04fdb2cb24f3","added_by":"auto","created_at":"2025-09-05 06:47:04","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1351407,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7054933/v1/6d1dc14a-d266-4725-81d2-c09db76307d4.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Prophylactic antibiotics in groin hernioplasty: a prospective cohort study on the prevention of surgical site infection","fulltext":[{"header":"INTRODUCTION ","content":"\u003cp\u003eGroin hernia repair is one of the most commonly performed surgical procedures worldwide, with mesh-based techniques established as the standard of care because of their reduced recurrence rates[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Despite being classified as a clean surgical procedure, surgical site infection (SSI) remains a significant complication, imposing a substantial clinical and economic burden[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. The high global volume of this procedure underscores the importance of effective evidence-based SSI prevention.\u003c/p\u003e\u003cp\u003e The routine use of prophylactic antibiotics in clean hernia repair remains a subject of considerable debate fueled by inconsistent evidence and conflicting clinical guidelines. Several high-quality systematic reviews and meta-analyses have reported that antibiotic prophylaxis can significantly reduce the risk of SSI. Landmark reviews by Al Riyees et al. and Sánchez-Manuel et al., along with a network meta-analysis by Boonchan et al., collectively demonstrate a protective effect, particularly in the context of mesh-based repairs where the presence of a foreign body increases infection risk[\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e–\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. A randomized controlled trial by Mazaki et al. reported a dramatic reduction in SSI from 13% in the placebo group to only 2% in the cefazolin group, highlighting the potential benefit in specific settings[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eHowever, this evidence is balanced by a strong counternarrative questioning of the necessity of universal prophylaxis. A comprehensive Cochrane review by Orelio et al. concluded that while a modest benefit exists, it is most apparent in high-risk environments, with little to no advantage in low-risk patient populations[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. This finding was echoed in a meta-analysis by Erdas et al., who suggested that the statistical significance of the benefit disappeared after removing outlier studies from their analysis[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Several prospective trials have further solidified this view, finding no significant difference in SSI rates between antibiotic and placebo groups in low-risk cohorts undergoing elective repair[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThis apparent contradiction in the literature suggests that the central issue is not whether antibiotics work but for whom they are necessary. The debate stems from a traditional ‘one-size-fits-all’ approach that fails to account for patient-specific risk factors, a limitation that modern evidence-based guidelines seek to address through structured, risk-stratified protocols[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Consequently, a paradigm shift toward this type of strategy is warranted, aligning with antimicrobial stewardship principles to avoid overuse and development of resistance[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Identifying patients with intrinsic risk factors is essential for prophylactic optimization. Factors such as obesity (high BMI) and prolonged operative time have been consistently identified as potential predictors of SSI in observational studies and systematic reviews[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. However, their independent impact requires further validation through well-designed prospective studies to clarify their real-world associations.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cp\u003e\u003cb\u003eStudy Design and Setting\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThis single-center, \u003cb\u003eprospective, observational cohort study\u003c/b\u003e was conducted at the Al-Gumhori Teaching Hospital, a tertiary care center in Sana'a, Yemen, from October 2023 to May 2024. This study aimed to evaluate the \u003cb\u003eassociation between\u003c/b\u003e prophylactic antibiotics and the incidence of surgical site infections (SSI) following open groin hernioplasty.\u003c/p\u003e\u003cp\u003e\u003cb\u003eParticipants\u003c/b\u003e\u003c/p\u003e\u003cp\u003eEligible participants were adult male patients (aged 17–80 years) scheduled for elective open groin hernioplasty. Exclusion criteria included recurrent hernias, emergency or complicated (e.g., incarcerated, strangulated) hernias, laparoscopic repairs, known immunosuppression, ongoing antibiotic therapy, a known allergy to cefazolin, or refusal to participate.\u003c/p\u003e\u003cp\u003e\u003cb\u003eCohort Definition and Exposure\u003c/b\u003e\u003c/p\u003e\u003cp\u003eEligible patients who provided informed consent were enrolled prospectively. The decision to administer prophylactic antibiotics was left to the discretion of the surgical treatment team, reflecting real-world clinical practice. Based on this decision, the patients were categorized into two exposure groups for analysis.\u003c/p\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eAntibiotic Group (exposed)\u003c/b\u003e: Patients who received a single intravenous dose of cefazolin (2 g) were administered 30–60 min prior to skin incision.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eNo Antibiotic Group (unexposed)\u003c/b\u003e: patients who did not receive prophylactic antibiotics.\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003cp\u003eAll patients underwent standardized open groin hernioplasty with polypropylene mesh reinforcement performed by experienced surgeons.\u003c/p\u003e\u003cp\u003e\u003cb\u003eOutcomes and Data Collection\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThe primary outcome was the incidence of SSI within 30 days postoperatively, as defined by the U.S.. Centers for Disease Control and Prevention (CDC) criteria[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Secondary outcomes included the identification of independent risk factors for SSI.\u003c/p\u003e\u003cp\u003eData were collected using a structured questionnaire covering demographic characteristics, medical history (comorbidities and smoking status), ASA of Anesthesiologists physical status score, and surgical details (operative duration). The patients were followed up via clinic visits at 7 and 30 days to assess signs of infection.\u003c/p\u003e\u003ch2\u003eStatistical Analysis\u003c/h2\u003e\u003cp\u003eThe required sample size was estimated a priori. To detect a difference in SSI rates between the exposed and unexposed groups (assuming rates of 5% and 15%, respectively) with an alpha of 0.05 and 80% power, a minimum of 47 patients per group were required. To account for potential dropouts, 50 patients were enrolled in each group for the analysis. All statistical analyses were performed using SPSS Statistics, Version 26.0 (IBM Corp., Armonk, NY, USA). Statistical significance was set at a two-sided p-value of \u0026lt; 0.05.\u003c/p\u003e\u003cp\u003eBaseline demographic and clinical characteristics were summarized using descriptive statistics and compared between the two exposure groups to assess potential confounding factors. Continuous variables are presented as mean ± standard deviation (SD) and were compared using independent t-tests or Mann–Whitney U tests. Categorical variables are presented as frequencies and percentages (n, %) and were compared using the chi-square test or Fisher’s exact test.\u003c/p\u003e\u003cp\u003eThe primary outcome, that is, the difference in SSI rates between the two groups, was analyzed using Fisher’s exact test. The results are expressed as odds ratios (OR) with 95% confidence intervals (CI). To identify the risk factors for SSI and adjust for potential confounding factors, both univariate and multivariate logistic regression analyses were performed. First, univariate models were constructed to assess the individual association of each potential risk factor (high BMI ≥ 30 kg/m ², high ASA score, prolonged operation time \u0026gt; 60 min, comorbidities, and smoking) with SSI development. Variables that were significant in the univariate analysis or deemed clinically important (including primary exposure to antibiotics) were then included in a multivariate logistic regression model to identify independent predictors and calculate the adjusted odds ratios (aORs). Finally, we conducted exploratory subgroup analyses to investigate the effects of antibiotics specifically in high-risk patient populations.\u003c/p\u003e\u003cp\u003e\u003cb\u003eEthical Considerations\u003c/b\u003e\u003c/p\u003e\u003cp\u003e This study was conducted in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Ethics Committee of the Faculty of Medicine and Health Sciences of Sana'a University, Sana'a, Yemen, and the Al-Gumhori Teaching Hospital. All participants provided written informed consent prior to enrollment.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003e\u003cstrong\u003eParticipant Characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOne hundred male patients who underwent elective open groin hernioplasty were enrolled in this study. Fifty patients received prophylactic antibiotics (Antibiotic Group), and 50 did not (no-antibiotic group). The baseline demographic and clinical characteristics were compared between the two groups \u003cstrong\u003e(\u003c/strong\u003eTable \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e\u003cstrong\u003e)\u003c/strong\u003e. \u003cstrong\u003eNo statistically significant differences were observed in the measured baseline variables\u003c/strong\u003e, suggesting that these specific factors were comparable between the two groups. The mean age of the cohort was 46.6\u0026thinsp;\u0026plusmn;\u0026thinsp;17.0 years. Overall, 10% of the patients had a BMI\u0026thinsp;\u0026ge;\u0026thinsp;30 kg/m \u0026sup2;, and 25% had an ASA score of 2.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eBaseline Characteristics of Study Participants\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCharacteristic\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAntibiotic Group (n\u0026thinsp;=\u0026thinsp;50)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eNo Antibiotic Group (n\u0026thinsp;=\u0026thinsp;50)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eTotal (n\u0026thinsp;=\u0026thinsp;100)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP-value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge (years), mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e45.8\u0026thinsp;\u0026plusmn;\u0026thinsp;16.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e47.4\u0026thinsp;\u0026plusmn;\u0026thinsp;17.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e46.6\u0026thinsp;\u0026plusmn;\u0026thinsp;17.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.632\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eBMI\u0026thinsp;\u0026ge;\u0026thinsp;30\u0026nbsp;kg/m\u0026sup2;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4 (8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6 (12%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10 (10%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.508\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSmoking\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12 (24%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15 (30%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27 (27%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.512\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eComorbidities\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8 (16%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13 (26%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e21 (21%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.243\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eASA Score 2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e11 (22%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14 (28%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 (25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.493\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eOperation Time (min), mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e56.2\u0026thinsp;\u0026plusmn;\u0026thinsp;12.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e58.5\u0026thinsp;\u0026plusmn;\u0026thinsp;14.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e57.4\u0026thinsp;\u0026plusmn;\u0026thinsp;13.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.418\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"5\"\u003e\n \u003cp\u003e\u003cstrong\u003eNotes\u003c/strong\u003e: \u003cem\u003eP-values were calculated using independent t-tests for continuous variables and Chi-square or Fisher\u0026rsquo;s exact tests for categorical variables.\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"5\"\u003e\n \u003cp\u003e\u003cstrong\u003eAbbreviations\u003c/strong\u003e: \u003cem\u003eSD, Standard Deviation; BMI, Body Mass Index; ASA, American Society of Anesthesiologists.\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003ePrimary Outcome: Surgical Site Infection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe overall incidence of surgical site infection (SSI) within 30 days was 10.0% (10/100). As detailed in Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e, the SSI rate in the Antibiotic Group was 6.0% compared with 14.0% in the no-antibiotic group. This absolute risk reduction of 8.0 percentage points did not reach statistical significance (p\u0026thinsp;=\u0026thinsp;0.318). The odds of developing an SSI were lower in the antibiotic group, but the confidence interval was wide and crossed 1.0 (OR 0.39, 95% CI 0.095\u0026ndash;1.613) (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eSurgical Site Infection Outcomes by Exposure Group\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eStatistical Test Results Measure\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAntibiotic Group (n\u0026thinsp;=\u0026thinsp;50)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eNo Antibiotic Group (n\u0026thinsp;=\u0026thinsp;50)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eStatistical Test\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSSI Cases\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3/50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7/50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSSI Rate (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e6.0%\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e14.0%\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eAbsolute Risk Reduction\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e8.0 percentage points\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eOdds Ratio\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.392 (95% CI: 0.095\u0026ndash;1.613)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eP-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e0.318\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFisher\u0026rsquo;s exact test\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSignificance\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003eNot Signi\u003c/strong\u003efi\u003cstrong\u003ecant (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026alpha;\u0026thinsp;=\u0026thinsp;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"4\"\u003e\n \u003cp\u003e\u003cstrong\u003eNote\u003c/strong\u003e: \u003cem\u003eThe p-value was calculated using Fisher\u0026rsquo;s exact test.\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eAbbreviations\u003c/strong\u003e: \u003cem\u003eSSI, Surgical Site Infection; CI, Confidence Interval.\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eRisk Factor Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eUnivariate Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eUnivariate analysis of the entire cohort revealed that these three factors were significantly associated with an increased risk of SSI \u003cstrong\u003e(\u003c/strong\u003eTable \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e\u003cstrong\u003e)\u003c/strong\u003e. A high BMI (\u0026ge;\u0026thinsp;30 kg/m \u0026sup2;) was the strongest predictor (OR 17.00, p\u0026thinsp;=\u0026thinsp;0.0007), followed by prolonged operation time (\u0026gt;\u0026thinsp;60 min) (OR 9.85, p\u0026thinsp;=\u0026thinsp;0.0025) and a higher ASA score of 2 (OR 5.61, p\u0026thinsp;=\u0026thinsp;0.0145).\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable id=\"Tab3\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eUnivariate Analysis of Risk Factors for Surgical Site Infection (N\u0026thinsp;=\u0026thinsp;100)\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRisk Factor\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOdds Ratio (OR)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e95% Confidence Interval (CI)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP-value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eHigh BMI (\u0026ge;\u0026thinsp;30\u0026nbsp;kg/m\u0026sup2;)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.07\u0026ndash;94.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0007\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eLong Operation (\u0026gt;\u0026thinsp;60 min)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.06\u0026ndash;47.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0025\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eHigh ASA Score (ASA 2)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.19\u0026ndash;26.48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0145\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eComorbidities\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.54\u0026ndash;8.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.397\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSmoking\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.46\u0026ndash;7.34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.510\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"4\"\u003e\n \u003cp\u003e\u003cstrong\u003eNotes\u003c/strong\u003e: \u003cem\u003eResults are from individual univariate logistic regression models for each risk factor. Significant p-values (\u0026lt;\u0026thinsp;0.05) are shown in bold font.\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eAbbreviations\u003c/strong\u003e: \u003cem\u003eOR, Odds Ratio; CI, Confidence Interval; BMI, Body Mass Index; ASA, American Society of Anesthesiologists.\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eMultivariate Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA multivariate logistic regression model was constructed to identify independent predictors of SSI (Table \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e). After adjusting for all variables, high BMI (aOR 17.93, p\u0026thinsp;=\u0026thinsp;0.041) and prolonged operation time (aOR 72.15, p\u0026thinsp;=\u0026thinsp;0.010) remained significant independent risk factors. A high ASA score was no longer a significant predictor in the adjusted model (p\u0026thinsp;=\u0026thinsp;0.862), suggesting that other factors confounded its effect. Administration of prophylactic antibiotics was associated with a strong protective trend (aOR 0.15), but this was not statistically significant (p\u0026thinsp;=\u0026thinsp;0.076). These results are shown in the forest plots in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable id=\"Tab4\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eMultivariate Logistic Regression Analysis of Independent SSI Risk Factors\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eVariable\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAdjusted Odds Ratio (aOR)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e95% Confidence Interval (CI)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP-value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eAntibiotic Prophylaxis (Yes vs. No)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.15\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.018\u0026ndash;1.28\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.076\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh BMI (\u0026ge;\u0026thinsp;30\u0026nbsp;kg/m\u0026nbsp;\u0026sup2;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.14\u0026ndash;282.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.041\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLong Operation (\u0026gt;\u0026thinsp;60 min)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e72.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.78\u0026ndash;1871.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.010\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eComorbidities\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.78\u0026ndash;248.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.077\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh ASA Score (ASA 2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.12\u0026ndash;12.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.862\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"4\"\u003e\n \u003cp\u003e\u003cem\u003eThe model simultaneously includes all listed variables. Significant p-values (\u0026lt;\u0026thinsp;0.05) are shown in bold font.\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003eAbbreviations: aOR, Adjusted Odds Ratio; CI, Confidence Interval; BMI, Body Mass Index; ASA, American Society of Anesthesiologists.\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eSubgroup Analysis in Patients with High Risk\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSubgroup analysis was performed to explore the effect of antibiotics on high-risk patient populations identified in the risk factor analysis \u003cstrong\u003e(\u003c/strong\u003eTable \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e\u003cstrong\u003e)\u003c/strong\u003e.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable id=\"Tab5\" border=\"1\" class=\"fr-table-selection-hover\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eSubgroup Analysis of Antibiotic Effectiveness in High-Risk Patients\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eHigh-Risk Subgroup\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAntibiotic Group SSI Rate (n/N)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eNo Antibiotic Group SSI Rate (n/N)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOdds Ratio (95% CI)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP-value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eHigh BMI (\u0026ge;\u0026thinsp;30 kg/m \u0026sup2;)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20.0% (1/5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e80.0% (4/5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.067 (0.003\u0026ndash;1.378)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.083\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eHigh ASA (ASA 2)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10.0% (1/10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e33.3% (5/15)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.231 (0.023\u0026ndash;2.354)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.345\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"5\"\u003e\n \u003cp\u003e\u003cstrong\u003eNote\u003c/strong\u003e: \u003cem\u003eP-values were calculated using Fisher\u0026rsquo;s exact test for each subgroup.\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eAbbreviations\u003c/strong\u003e: \u003cem\u003eSSI, Surgical Site Infection; CI, Confidence Interval; BMI, Body Mass Index; ASA, American Society of Anesthesiologists.\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eIn patients with high BMI, prophylactic antibiotics were associated with a strong trend toward a protective effect, reducing the SSI rate from 80.0\u0026ndash;20.0%. However, this finding was not statistically significant (p\u0026thinsp;=\u0026thinsp;0.083), likely because of the small number of patients in this subgroup (n\u0026thinsp;=\u0026thinsp;10). A moderately non-significant effect was also observed in patients with high ASA scores.\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003e\u003cb\u003eThis prospective cohort study\u003c/b\u003e did not find a statistically significant association between routine prophylactic antibiotics and SSI rates in an unselected population of patients who underwent groin hernioplasty. The SSI rate was 6.0% in the antibiotic group versus 14.0% in the no-antibiotic group (p\u0026thinsp;=\u0026thinsp;0.318), which supports a more selective prophylactic approach. The 8.0 percentage point absolute risk reduction that we observed, although not statistically significant, is directionally consistent with the modest benefits reported in major systematic reviews[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eOur results contribute to the existing and important controversies. Foundational work, including Cochrane reviews by Sanchez-Manuel et al. and Orelio et al. (2020), has long questioned the value of universal prophylaxis, particularly in low-risk settings[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Recent evidence suggests that while antibiotics can be effective, the effect is context-dependent, with the greatest benefit observed in high-risk environments or mesh-based repairs[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Our study provides crucial primary data that reinforce this narrative: the overall benefit is not statistically robust in a mixed-risk real-world cohort.\u003c/p\u003e\u003cp\u003eThe most important findings of our study emerged from the multivariate analysis, which revealed that only a high BMI (\u0026gt;\u0026thinsp;30 kg/m \u0026sup2;) and prolonged operative time (\u0026gt;\u0026thinsp;60 min) were significant independent predictors of SSI. This analysis is critical in observational studies because it helps statistically adjust for baseline differences and isolate the impact of individual risk factors. Notably, the initially significant association with a high ASA score was attenuated after multivariate adjustment, indicating that it may serve as a proxy for other risk factors. This finding emphasizes the necessity of shifting from universal prophylaxis to a targeted risk-stratified approach.\u003c/p\u003e\u003cp\u003eOur finding that obesity is a powerful independent predictor is strongly supported by literature. A systematic review by Quiroga-Centeno et al. (2022) confirmed this robust association in the repair of abdominal wall hernias, likely mediated by factors such as impaired wound healing and poor tissue perfusion[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Similarly, the link between prolonged operative time and increased SSI risk has been well established, as confirmed in a systematic review by Cheng et al. (2017)[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eClinically, these results provide strong evidence to support targeted antibiotic prophylaxis in high-risk patients. Our subgroup analysis, although limited by a small sample size, showed a substantial trend toward a protective benefit in patients with a high BMI who received antibiotics (SSI rate 20% vs. 80%; p\u0026thinsp;=\u0026thinsp;0.083), indicating a clinically meaningful effect that warrants further investigation. This selective strategy aligns with the modern principles of antimicrobial stewardship[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThis study has several limitations. First, \u003cb\u003eits observational design means that we can only report associations and cannot establish causality.\u003c/b\u003e Although we performed a multivariate analysis to control for the measured variables, the risk of \u003cb\u003eunmeasured confounding\u003c/b\u003e factors remained. For example, surgeons may have been more inclined to administer antibiotics to patients that they intuitively perceived as having a higher risk for reasons not captured in our data (confounding by indication). Third, this single-center, male-only cohort study limited the generalizability of our findings. Finally, the study's sample size was likely underpowered to detect a statistically significant difference in the primary outcome, particularly in subgroup analyses.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eIn conclusion, this prospective cohort study found that routine prophylactic antibiotic administration was not significantly associated with a reduced surgical site infection rate in an unselected population of patients undergoing groin hernioplasty. The most important independent risk factors for developing infection were high BMI (\u0026ge;\u0026thinsp;30 kg/m \u0026sup2;) and prolonged operative time (\u0026gt;\u0026thinsp;60 min). These findings strongly support a shift away from universal prophylaxis toward a selective, risk-stratified strategy in which antibiotics are targeted to patients with these specific risk factors to optimize outcomes and support antimicrobial stewardship. Larger randomized trials or multicenter cohort studies are needed in the future to confirm the benefits of this targeted approach and to inform the next generation of evidence-based clinical guidelines.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthical Approval and Consent to Participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was conducted in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Ethics Committee of the Faculty of Medicine and Health Sciences of Sana\u0026apos;a University, Sana\u0026apos;a, Yemen, and the Al-Gumhori Teaching Hospital. All participants provided written informed consent prior to enrollment.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for Publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable. (This is used if your manuscript contains identifying patient information, such as photos or detailed case descriptions, which yours does not).\u003c/p\u003e\n\u003ch2\u003eCompeting Interests\u003c/h2\u003e\n\u003cp\u003eThe authors declare that they have no conflicts of interest.\u003c/p\u003e\n\u003ch2\u003eFunding\u003c/h2\u003e\n\u003cp\u003eThis research received no specific grants from any funding agency in the public, commercial, or not-for-profit sector.\u003c/p\u003e\n\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\n\u003cp\u003eWMG designed the study, collected data, and drafted the manuscript. LMA and YAO supervised the study and revised the manuscript critically. MMA and HMJ contributed to data analysis and manuscript review. All authors have read and approved the final version of the manuscript.\u003c/p\u003e\n\u003ch2\u003eData Availability\u003c/h2\u003e\n\u003cp\u003eThe data supporting the findings of this study are available from the corresponding author upon reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eHerniaSurge Group. International guidelines for groin hernia management. Hernia 2018;22:1\u0026ndash;165. https://doi.org/10.1007/s10029-017-1668-x.\u003c/li\u003e\n\u003cli\u003eSeidelman JL, Mantyh CR, Anderson DJ. Surgical Site Infection Prevention: A Review. JAMA 2023;329:244\u0026ndash;52. https://doi.org/10.1001/jama.2022.24075.\u003c/li\u003e\n\u003cli\u003eAl Riyees L, Al Madani W, Firwana N, Balkhy HH, Ferwana M, Alkhudhayri A. Antibiotic Prophylaxis against Surgical Site Infection after Open Hernia Surgery: A Systematic Review and Meta-Analysis. Eur Surg Res 2021;62:121\u0026ndash;33. https://doi.org/10.1159/000517404.\u003c/li\u003e\n\u003cli\u003eBoonchan T, Wilasrusmee C, McEvoy M, Attia J, Thakkinstian A. Network meta-analysis of antibiotic prophylaxis for prevention of surgical-site infection after groin hernia surgery. Br J Surg 2017;104:e106\u0026ndash;17. https://doi.org/10.1002/bjs.10441.\u003c/li\u003e\n\u003cli\u003eSanchez-Manuel FJ, Lozano-Garc\u0026iacute;a J, Seco-Gil JL. Antibiotic prophylaxis for hernia repair. Cochrane Database Syst Rev 2007:CD003769. https://doi.org/10.1002/14651858.CD003769.pub3.\u003c/li\u003e\n\u003cli\u003eMazaki T, Mado K, Masuda H, Shiono M, Tochikura N, Kaburagi M. A randomized trial of antibiotic prophylaxis for the prevention of surgical site infection after open mesh-plug hernia repair. Am J Surg 2014;207:476\u0026ndash;84. https://doi.org/10.1016/j.amjsurg.2013.01.047.\u003c/li\u003e\n\u003cli\u003eOrelio CC, van Hessen C, Sanchez-Manuel FJ, Aufenacker TJ, Scholten RJ. Antibiotic prophylaxis for prevention of postoperative wound infection in adults undergoing open elective inguinal or femoral hernia repair. Cochrane Database Syst Rev 2020;4:CD003769. https://doi.org/10.1002/14651858.CD003769.pub5.\u003c/li\u003e\n\u003cli\u003eErdas E, Medas F, Pisano G, Nicolosi A, Cal\u0026ograve; PG. Antibiotic prophylaxis for open mesh repair of groin hernia: systematic review and meta-analysis. Hernia 2016;20:765\u0026ndash;76. https://doi.org/10.1007/S10029-016-1536-0.\u003c/li\u003e\n\u003cli\u003eRazack A, Kapoor KK, Tambat RM. THE ROLE OF SINGLE DOSE ANTIBIOTIC PROPHYLAXIS IN OPEN MESH REPAIR OF INGUINAL HERNIA : A PROSPECTIVE, DOUBLE BLIND RANDOMIZED TRIAL. J Evol Med Dent Sci 2015;4:6017\u0026ndash;26. https://doi.org/10.14260/JEMDS/2015/877.\u003c/li\u003e\n\u003cli\u003eSingh V, Kumar M, Kumar A. EVALUATION OF THE ROLE OF PROPHYLACTIC ANTIBIOTIC VERSUS NO ANTIBIOTIC IN CASES OF GROIN HERNIA SURGERY. International Journal of Medical and Pharma Research 2015;4:37\u0026ndash;40.\u003c/li\u003e\n\u003cli\u003eSartelli M, Coccolini F, Labricciosa FM, Al Omari AbdelKarimH, Bains L, Baraket O, et al. Surgical Antibiotic Prophylaxis: A Proposal for a Global Evidence-Based Bundle. Antibiotics 2024;13:100. https://doi.org/10.3390/antibiotics13010100.\u003c/li\u003e\n\u003cli\u003eKlifto KM, Rydz AC, Biswas S, Hultman CS, Erdmann D, Phillips BT. Evidence-Based Medicine: Systemic Perioperative Antibiotic Prophylaxis for Prevention of Surgical-Site Infections in Plastic and Reconstructive Surgery. Plast Reconstr Surg 2023;152:1154E-1182E. https://doi.org/10.1097/PRS.0000000000010608.\u003c/li\u003e\n\u003cli\u003eQuiroga-Centeno AC, Quiroga-Centeno CA, Guerrero-Mac\u0026iacute;as S, Navas-Quintero O, G\u0026oacute;mez-Ochoa SA. Systematic review and meta-analysis of risk factors for Mesh infection following Abdominal Wall Hernia Repair Surgery. Am J Surg 2022;224:239\u0026ndash;46. https://doi.org/10.1016/j.amjsurg.2021.12.024.\u003c/li\u003e\n\u003cli\u003eCheng H, Chen BP-H, Soleas IM, Ferko NC, Cameron CG, Hinoul P. Prolonged Operative Duration Increases Risk of Surgical Site Infections: A Systematic Review. Surg Infect (Larchmt) 2017;18:722\u0026ndash;35. https://doi.org/10.1089/sur.2017.089.\u003c/li\u003e\n\u003cli\u003eBerri\u0026oacute;s-Torres SI, Umscheid CA, Bratzler DW, Leas B, Stone EC, Kelz RR, et al. Centers for Disease Control and Prevention Guideline for the Prevention of Surgical Site Infection, 2017. JAMA Surg 2017;152:784\u0026ndash;91. https://doi.org/10.1001/JAMASURG.2017.0904.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"hernioplasty, surgical site infection, antibiotic prophylaxis, groin hernia, wound infection","lastPublishedDoi":"10.21203/rs.3.rs-7054933/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7054933/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e The role of prophylactic antibiotics in preventing surgical site infections (SSI) in clean procedures such as groin hernioplastyremains controversial. This study aimed to evaluate the \u003cstrong\u003eassociation between\u003c/strong\u003e antibiotic prophylaxis and SSI rates in a real-world setting and identify independent risk factors for SSI.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e This single-center, \u003cstrong\u003eprospective cohort study\u003c/strong\u003e was conducted at Al-Gumhori Teaching Hospital, Sana'a, Yemen. A total of 100 male patients undergoing elective open groin hernioplasty were prospectively followed. Patients were categorized into two groups based on the treating surgeon's decision: those who received a single dose of intravenous cefazolin (Antibiotic Group, n=50), and those who did not receive antibiotic prophylaxis (No Antibiotic Group, n=50). The primary outcome was the incidence of SSI within 30 days. Univariate and multivariate logistic regression analyses were performed to identify the risk factors for SSI.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e The SSI rate was 6.0% in the antibiotic group and 14.0% in the non-antibiotic group (overall rate 10.0%), respectively (p = 0.318). Multivariate logistic regression analysis identified \u003cstrong\u003ehigh BMI (Adjusted OR 17.93, p = 0.041) and prolonged operative time \u0026gt;60 min (Adjusted OR 72.15, p = 0.010) as the only significant independent predictors of SSI.\u003c/strong\u003e Antibiotic prophylaxis showed a strong but not statistically significant protective trend after adjusting for other factors (Adjusted OR odds ratio [OR], 0.15; 95% confidence interval [CI], 0.018–1.28; p = 0.076).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e \u0026nbsp;Routine prophylactic antibiotic administration was not significantly associated with a reduction in the SSI rates. A high BMI and prolonged operative time are key drivers of infection risk, supporting a risk-stratified approach in which prophylaxis is targeted to high-risk patients.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical trial number:\u003c/strong\u003e not applicable.\u003c/p\u003e","manuscriptTitle":"Prophylactic antibiotics in groin hernioplasty: a prospective cohort study on the prevention of surgical site infection","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-23 02:39:33","doi":"10.21203/rs.3.rs-7054933/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"05b1dc45-21cd-4e82-9c5d-7a0ba1efc3b1","owner":[],"postedDate":"July 23rd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-09-05T06:38:56+00:00","versionOfRecord":[],"versionCreatedAt":"2025-07-23 02:39:33","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7054933","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7054933","identity":"rs-7054933","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}