European Journal of Cardiovascular Medicine

Surgical site infection (SSI) remains one of the most significant complications following surgical procedures, contributing substantially to patient morbidity, prolonged hospital stays, and increased healthcare costs worldwide. According to the Centers for Disease Control and Prevention (CDC), SSI is defined as an infection that occurs at or near the surgical incision within 30 days postoperatively and is characterized by purulent drainage, positive bacterial culture, or clinical signs of infection such as redness, swelling, tenderness, or warmth at the surgical site^[1,2].

The development of SSI is multifactorial, influenced by factors such as the patient's immune status, surgical technique, duration of surgery, and the use of prophylactic antibiotics. Historically, before the advent of antibiotics, the rates of infection following surgery were alarmingly high, leading to increased postoperative mortality and morbidity. The antibiotic era, commencing over five decades ago, revolutionized surgical outcomes by significantly reducing infection rates and improving recovery^[3]. Prophylactic antibiotics, given before or during surgery, are intended to reduce the microbial load at the surgical site, thus preventing infection.

However, the widespread and sometimes inappropriate use of prophylactic antibiotics has led to concerns about antibiotic resistance, increased healthcare costs, and adverse drug reactions. The indiscriminate use of antibiotics, particularly in clean surgical cases where infection risk is naturally low, has been questioned. The balance between preventing SSIs and minimizing antibiotic overuse is a critical consideration in modern surgical practice^[4].

Clean surgeries are defined as elective procedures in which no inflammation is encountered and the respiratory, alimentary, genital, or uninfected urinary tracts are not entered. The infection risk in such cases is relatively low, generally less than 2%, when strict aseptic techniques are employed. The role of prophylactic antibiotics in these surgeries remains controversial, with some studies supporting their use while others suggest limited benefit, raising questions about necessity, cost-effectiveness, and the risk of promoting antibiotic resistance^[5].

Several clinical trials and meta-analyses have evaluated the efficacy of single-dose preoperative antibiotics versus multiple-dose or no antibiotic prophylaxis. Ponce B et al. (2014)^[6] demonstrated that a single preoperative dose of Cefazolin was as effective as multiple postoperative doses in preventing SSI after cholecystectomy, with infection rates of 3% and 5%, respectively.

Aim

To evaluate the efficacy of preoperative antibiotic prophylaxis versus no prophylaxis in reducing surgical site infections in clean surgical procedures.

Objectives

1. To compare the incidence of surgical site infections in patients undergoing clean surgeries with and without preoperative antibiotic prophylaxis.
2. To assess the role of single-dose preoperative antibiotics in preventing postoperative infections in clean surgical wounds.
3. To analyze the impact of prophylactic antibiotic use on postoperative outcomes and complications in clean surgery patients.

Source of Data

Data was collected from patients undergoing clean surgical procedures at KAHER’s JGMM Medical College and affiliated hospitals in Hubballi, Karnataka.

Study Design

This was a prospective, cross-sectional, comparative study aimed at evaluating the efficacy of preoperative antibiotic prophylaxis versus no prophylaxis in preventing surgical site infections in clean surgeries.

Study Location

The study was conducted in the Department of General Surgery at KAHER’s JGMM Medical College and associated KLE Cooperative Hospital and other KAHER institutes in Hubballi.

Study Duration

The study was conducted over a period of five months, including four months of patient recruitment and one month of data analysis.

Sample Size

A total of 120 patients were enrolled, divided equally into two groups: 60 patients received preoperative prophylactic antibiotics (Injection Ceftriaxone 1g IV at surgery start), and 60 patients did not receive prophylactic antibiotics.

Inclusion Criteria

• Patients aged 18 to 75 years undergoing elective clean surgical procedures.
• Patients with clean, uncontaminated surgical wounds admitted at least two days prior to surgery.
• Patients who provided informed consent for participation.

Exclusion Criteria

• Patients with contaminated or dirty wounds.
• Patients with wound dehiscence or burst abdomen.
• History of previous surgeries.
• Known systemic illnesses including diabetes mellitus, hypertension, tuberculosis, or other chronic inflammatory diseases.
• Patients aged below 18 or above 75 years.

Procedure and Methodology

After institutional ethics committee approval, eligible patients were recruited and randomized into two groups. Preoperative prophylactic antibiotic group received Injection Ceftriaxone 1g intravenously at the time of surgery initiation. The non-prophylactic group did not receive antibiotics prior to surgery. All surgeries were performed under strict aseptic conditions by experienced surgeons.

Patients were monitored postoperatively for signs of surgical site infection up to 30 days after surgery. Data on patient demographics, surgical procedure, intraoperative and postoperative complications, wound status, and SSI occurrence were documented meticulously.

Sample Processing

Relevant investigations such as Complete Blood Count (CBC), Random Blood Sugar (RBS), Bleeding Time (BT), Clotting Time (CT), Renal Function Test (RFT), Liver Function Test (LFT), and screening for HIV, Hepatitis B, and Hepatitis C were performed preoperatively. Ultrasonography was done as required for clinical assessment.

Statistical Methods

Data were entered into Microsoft Excel and analyzed using SPSS software version 29.0. Continuous variables were expressed as mean ± standard deviation and compared using Student’s t-test or ANOVA where appropriate. Categorical variables were expressed as proportions and analyzed using Chi-square tests. Normality of data was assessed using Shapiro-Wilk and Kolmogorov-Smirnov tests. A p-value < 0.05 was considered statistically significant.

Data Collection

Data collection was performed through structured proformas capturing patient history, clinical examination, surgical details, antibiotic administration, and postoperative follow-up findings. Patients were followed up clinically for one month postoperatively for detection of surgical site infection or any complications

Table 1: Baseline Demographic and Clinical Profile of Study Participants (n=120)

Table 1 presents the baseline demographic and clinical characteristics of the study participants divided into the antibiotic prophylaxis group and the no antibiotic group, each consisting of 60 patients. The mean age was comparable between groups, with 42.7 (±13.5) years in the antibiotic group and 44.1 (±14.2) years in the no antibiotic group, showing no statistically significant difference (t = -0.51, p = 0.61). Gender distribution was also similar, with males comprising 63.3% and 68.3% of the respective groups (χ² = 0.33, p = 0.57). Body mass index (BMI) and duration of surgery were closely matched, averaging 24.9 (±3.6) vs. 25.3 (±3.8) kg/m² and 78.2 (±22.9) vs. 81.4 (±24.5) minutes, respectively, with no significant differences (p > 0.4). Smoking history was reported in 23.3% of the antibiotic group and 26.7% of the no antibiotic group (χ² = 0.15, p = 0.70), indicating homogeneity in baseline risk factors.

Table 2: Incidence of Surgical Site Infections (SSI) in Patients with and without Preoperative Antibiotics (n=120)

*Significant difference (P < 0.05)

Table 2 highlights the incidence of surgical site infections (SSI) between the two groups. The antibiotic group showed a significantly lower SSI rate of 6.7% (4 patients) compared to 25.0% (15 patients) in the no antibiotic group (χ² = 8.15, p = 0.004). This represents a significant absolute risk reduction, with the 95% confidence interval ranging from 8.3% to 31.7%. Correspondingly, the majority of patients in the antibiotic group remained free of infection (93.3%) versus 75.0% in the control group.

Table 3: Role of Single-Dose Preoperative Antibiotic in Preventing Postoperative Infections (n=120)

*Significant difference (P < 0.05), rehospitalization shows trend but not statistically significant.

Table 3 focuses on postoperative infectious complications related to the use of single-dose preoperative antibiotics. The antibiotic group had significantly fewer cases of postoperative fever (8.3% vs. 21.7%, p = 0.04) and wound discharge (5.0% vs. 16.7%, p = 0.04) compared to the no antibiotic group. Rehospitalization rates due to SSI were lower in the antibiotic group (1.7% vs. 10.0%), showing a trend toward significance but not reaching the conventional threshold (p = 0.06). These findings suggest that single-dose prophylaxis effectively reduces common postoperative infectious events.

Table 4: Impact of Prophylactic Antibiotic Use on Postoperative Outcomes and Complications (n=120)

*Significant difference (P < 0.05)

Table 4 describes the overall impact of prophylactic antibiotic administration on postoperative outcomes and complications. The antibiotic group experienced a significantly shorter hospital stay, with a mean duration of 4.1 days compared to 5.3 days in the no antibiotic group (t = -5.22, p < 0.001). Postoperative pain assessed by VAS scores was also significantly lower in the antibiotic group (3.6 vs. 4.2, p = 0.006). Notably, antibiotic-related side effects were reported only in the prophylaxis group (11.7%), which was statistically significant (p = 0.007). Although readmission rates within 30 days were lower in the antibiotic group (3.3% vs. 11.7%), this difference was not statistically significant (p = 0.07). These results emphasize the benefits of prophylactic antibiotics in improving clinical outcomes while acknowledging the risk of related adverse effects.

Baseline Demographic and Clinical Profile (Table 1): The demographic characteristics of the study groups were well matched, with no significant differences in age, gender distribution, BMI, duration of surgery, or smoking history. This similarity between the antibiotic prophylaxis and no antibiotic groups ensures that confounding factors were minimized. Comparable baseline profiles have also been reported in similar studies, such as Wassef MA et al. (2012)^[7] and Liu J et al. (2018)^[8], who emphasized the importance of homogenous study populations to assess the true impact of prophylactic antibiotics on surgical site infection (SSI) rates. The mean age in this study (approx. 43-44 years) aligns with many elective clean surgery cohorts reported in previous investigations Ariyan S et al. (2015)^[9]. Additionally, duration of surgery, a known risk factor for SSI, was closely matched, consistent with findings from Allegranzi B et al. (2016)^[10], which showed infection rates increase with longer operative times.

Incidence of Surgical Site Infections (Table 2): The significant reduction in SSI incidence in the antibiotic group (6.7%) compared to the no antibiotic group (25.0%) supports the efficacy of preoperative antibiotic prophylaxis. This finding is consistent with several landmark studies; Zhang Y et al. (2014)^[11] demonstrated a similar protective effect of preoperative cefazolin in reducing SSI rates compared to no or delayed antibiotic use. Gandra S et al. (2019)^[3] also advocated for prophylaxis in clean surgical cases, noting reductions in infection rates with appropriate antibiotic administration. The absolute risk reduction and confidence intervals indicate a robust benefit, confirming that prophylactic antibiotics significantly prevent postoperative infections in clean wounds.

Role of Single-Dose Preoperative Antibiotic in Preventing Postoperative Infections (Table 3): The lower rates of postoperative fever and wound discharge in the prophylaxis group further highlight the clinical benefits of antibiotic use. These results corroborate findings from Karlatti S et al. (2016)^[12], who observed that single-dose prophylaxis before incision decreased infectious complications and promoted better postoperative recovery. The rehospitalization rates due to SSI, while showing a positive trend, did not reach statistical significance, possibly due to sample size limitations. Nevertheless, these trends parallel observations by Wassef MA et al. (2012)^[7], who emphasized that antibiotic prophylaxis reduces both minor and major postoperative infectious morbidities.

Impact of Prophylactic Antibiotic Use on Postoperative Outcomes and Complications (Table 4): The antibiotic group had significantly shorter hospital stays and lower postoperative pain scores, indicating not only reduced infection risk but also improved overall recovery and patient comfort. Similar conclusions were drawn by Chauveaux D. (2015)^[13], who reported that effective prophylaxis reduces hospitalization time and associated healthcare costs. However, antibiotic-related side effects were seen exclusively in the prophylaxis group, emphasizing the need for cautious antibiotic use and monitoring to avoid adverse drug reactions. The slightly lower, though not significant, readmission rates in the antibiotic group suggest a clinical benefit that warrants further study with larger cohorts.

The present cross-sectional study demonstrates that preoperative antibiotic prophylaxis significantly reduces the incidence of surgical site infections in clean surgical procedures. Patients receiving a single-dose prophylactic antibiotic exhibited markedly lower rates of postoperative infections, reduced hospital stay duration, and decreased postoperative complications compared to those who did not receive prophylaxis. Although antibiotic-related side effects were observed, the benefits in infection control and improved recovery underscore the importance of judicious antibiotic use in clean surgeries. These findings support the continued use of preoperative prophylactic antibiotics to minimize surgical morbidity while emphasizing the need for careful monitoring to mitigate adverse effects.

LIMITATIONS OF THE STUDY

This study has several limitations. First, the sample size was relatively small (n=120), which may limit the generalizability of the findings and the power to detect differences in less frequent outcomes such as rehospitalization. Second, the study was conducted at a single tertiary care center, potentially limiting applicability across diverse healthcare settings. Third, the follow-up period was limited to 30 days, possibly missing late-onset infections. Fourth, antibiotic-related adverse events were not extensively characterized, and long-term consequences of prophylaxis were not assessed. Lastly, the study did not control for all potential confounders such as varying surgical techniques or comorbidities beyond basic exclusion criteria, which could influence SSI risk.

1. Chen PJ, Hua YM, Toh HS, Lee MC. Topical antibiotic prophylaxis for surgical wound infections in clean and clean-contaminated surgery: a systematic review and meta-analysis. BJS open. 2021 Nov 1;5(6):zrab125.
2. Allen J, David M, Veerman JL. Systematic review of the cost-effectiveness of preoperative antibiotic prophylaxis in reducing surgical-site infection. BJS open. 2018 Jun;2(3):81-98.
3. Gandra S, Trett A, Alvarez-Uria G, Solomkin JS, Laxminarayan R. Is the efficacy of antibiotic prophylaxis for surgical procedures decreasing? Systematic review and meta-analysis of randomized control trials. Infection Control & Hospital Epidemiology. 2019 Feb;40(2):133-41.
4. Anjum N, Ren J, Wang G, Li G, Wu X, Dong H, Wu Q, Li J. A randomized control trial of preoperative oral antibiotics as adjunct therapy to systemic antibiotics for preventing surgical site infection in clean contaminated, contaminated, and dirty type of colorectal surgeries. Diseases of the Colon & Rectum. 2017 Dec 1;60(12):1291-8.
5. Jalalzadeh H, Groenen H, Buis DR, Dreissen YE, Goosen JH, Ijpma FF, van der Laan MJ, Schaad RR, Segers P, van der Zwet WC, Griekspoor M. Efficacy of different preoperative skin antiseptics on the incidence of surgical site infections: a systematic review, GRADE assessment, and network meta-analysis. The Lancet Microbe. 2022 Oct 1;3(10):e762-71.
6. Ponce B, Raines BT, Reed RD, Vick C, Richman J, Hawn M. Surgical site infection after arthroplasty: comparative effectiveness of prophylactic antibiotics: do surgical care improvement project guidelines need to be updated?. JBJS. 2014 Jun 18;96(12):970-7.
7. Wassef MA, Hussein A, Abdul Rahman EM, El-Sherif RH. A prospective surveillance of surgical site infections: Study for efficacy of preoperative antibiotic prophylaxis. African journal of microbiology research. 2012 Mar 30;6(12):3072-8.
8. Liu J, Li N, Hao J, Li Y, Liu A, Wu Y, Cai M. Impact of the antibiotic stewardship program on prevention and control of surgical site infection during peri-operative clean surgery. Surgical Infections. 2018 Apr 1;19(3):326-33.
9. Ariyan S, Martin J, Lal A, Cheng D, Borah GL, Chung KC, Conly J, Havlik R, Lee WA, McGrath MH, Pribaz J. Antibiotic prophylaxis for preventing surgical-site infection in plastic surgery: an evidence-based consensus conference statement from the American Association of Plastic Surgeons. Plastic and reconstructive surgery. 2015 Jun 1;135(6):1723-39.
10. Allegranzi B, Bischoff P, De Jonge S, Kubilay NZ, Zayed B, Gomes SM, Abbas M, Atema JJ, Gans S, van Rijen M, Boermeester MA. New WHO recommendations on preoperative measures for surgical site infection prevention: an evidence-based global perspective. The Lancet Infectious Diseases. 2016 Dec 1;16(12):e276-87.
11. Zhang Y, Dong J, Qiao Y, He J, Wang T, Ma S. Efficacy and safety profile of antibiotic prophylaxis usage in clean and clean-contaminated plastic and reconstructive surgery: a meta-analysis of randomized controlled trials. Annals of Plastic Surgery. 2014 Jan 1;72(1):121-30.
12. Karlatti S, Havannavar I. A comparative prospective study of preoperative antibiotic prophylaxis in the prevention of surgical site infections. International Surgery Journal. 2016 Jan;3(1):141-5.
13. Chauveaux D. Preventing surgical-site infections: measures other than antibiotics. Orthopaedics & Traumatology: Surgery & Research. 2015 Feb 1;101(1):S77-83.