Surgical site infections (SSIs) represent a persistent postoperative complication, significantly contributing to patient morbidity, extended hospital stays, and increased healthcare costs globally. In abdominal surgery, the risk of SSIs is particularly elevated due to the proximity of visceral organs and potential exposure to endogenous microbial flora, with reported incidence rates ranging from 5% to 30% depending on patient-specific factors, surgical techniques, and preventive measures [1, 2]. Preoperative antibiotic prophylaxis (PAP) has emerged as a widely endorsed strategy for infection control, with evidence demonstrating its efficacy in reducing SSI rates across various surgical fields, including hernia repair and upper gastrointestinal procedures [1, 3]. Systematic reviews and meta-analyses have underscored its role in mitigating postoperative complications, particularly when administered as a single dose prior to incision [3, 6].

Despite its established benefits, the effectiveness of PAP in specific contexts, such as resource-constrained settings, remains underexplored. Factors such as local microbial profiles, antibiotic resistance patterns, and healthcare infrastructure may influence outcomes, necessitating region-specific investigations [4, 5]. In India, where abdominal surgeries are frequently performed to address conditions like appendicitis, gastrointestinal malignancies, and trauma, optimizing perioperative care is paramount. Government Medical College, Srikakulam, a tertiary care institution in Andhra Pradesh, serves a heterogeneous population with diverse risk profiles, providing an ideal setting to assess PAP’s impact in a real-world clinical environment.

While global guidelines advocate for PAP, local data on its efficacy in India are limited, and concerns about antibiotic overuse, resistance, and adverse effects—such as allergic reactions or Clostridium difficile infections—highlight the need for context-specific evidence [2, 5]. For instance, studies in similar settings, such as appendectomy cohorts in Thailand, have identified variable SSI risks and prophylaxis outcomes, emphasizing the importance of tailored approaches [5]. Furthermore, debates persist regarding optimal dosing regimens, with single-dose protocols showing promise over multiple doses in balancing efficacy and safety [6]

This study aimed to assess the efficacy of preoperative antibiotic prophylaxis in reducing SSIs among patients undergoing abdominal surgery at Government Medical College, Srikakulam, over a one-year period from January 2020 to December 2020. Secondary objectives included evaluating its effects on hospital stay duration, non-SSI complications, and safety profile.

This prospective cohort study was conducted at Government Medical College, Srikakulam, Andhra Pradesh, India, over a one-year period from January 1, 2020, to December 31, 2020, to evaluate the efficacy of preoperative antibiotic prophylaxis (PAP) in reducing surgical site infections (SSIs) following abdominal surgery. A total of 100 patients were enrolled and allocated into two groups: 50 received PAP (PAP group), and 50 received no preoperative antibiotics (control group). Randomization was performed using a computer-generated sequence to ensure unbiased group assignment.

Eligible participants were adults aged 18–75 years undergoing elective or emergency abdominal surgery. Exclusion criteria comprised preoperative infections, antibiotic administration within 48 hours prior to surgery, known Ceftriaxone allergy, or lack of consent. The PAP group received a single 1 g intravenous dose of Ceftriaxone 30–60 minutes before incision, per standard guidelines, while the control group followed identical perioperative protocols without prophylaxis.

The primary endpoint was SSI incidence within 30 days post-surgery, classified as superficial or deep per Centers for Disease Control and Prevention (CDC) criteria. Wound swabs from suspected SSIs underwent microbiological culture and sensitivity testing. Secondary endpoints included hospital stay duration, non-SSI complications (e.g., wound dehiscence, pneumonia), and antibiotic-related adverse events.

Data on patient demographics (age, sex, BMI, ASA score), operative details, and outcomes were collected by blinded investigators using standardized forms. Statistical analyses employed the chi-square test for categorical data (e.g., SSI rates), Fisher’s exact test for small sample comparisons (e.g., SSI types, pathogens), and the Mann-Whitney U test for continuous variables (e.g., hospital stay). Significance was set at p < 0.05. Necessary permissons were obtained from concerned authorities before starting the study, and all participants provided written informed consent.

A total of 100 patients undergoing abdominal surgery were enrolled in this study, with 50 assigned to the preoperative antibiotic prophylaxis (PAP) group and 50 to the control group. Baseline characteristics, including age, sex, body mass index (BMI), and American Society of Anesthesiologists (ASA) scores, were comparable between groups (p > 0.05 for all comparisons), confirming effective randomization and minimal confounding (Table 1).

Table 1: Baseline Characteristics and Study Population

The overall incidence of surgical site infections (SSIs) was 15% (15/100 patients). In the PAP group, 5 patients (10%) developed SSIs, compared to 10 patients (20%) in the control group, a difference that was statistically significant (p = 0.037, chi-square test) (Table 2). This corresponds to a relative risk reduction of 50% and an absolute risk reduction of 10% (95% confidence interval [CI], 0.8%–19.2%), indicating a protective effect of PAP against SSIs.

Table 2: Incidence of Surgical Site Infections (SSIs)

Among the 15 SSIs, 10 (66.7%) were superficial and 5 (33.3%) were deep infections (Table 3). In the PAP group, 3 of 5 SSIs (60%) were superficial and 2 (40%) were deep, while in the control group, 7 of 10 SSIs (70%) were superficial and 3 (30%) were deep. The trend toward fewer superficial SSIs in the PAP group was not statistically significant (p = 0.15, Fisher’s exact test), nor was the difference in deep SSIs (p = 0.63, Fisher’s exact test).

Table 3: Classification of Surgical Site Infections

Table 4: Microbiological Analysis of SSIs

Secondary outcomes included hospital stay and non-SSI complications (Table 5). The median length of hospital stay was 6 days (interquartile range [IQR], 5–8) in the PAP group and 7 days (IQR, 6–9) in the control group, a statistically significant reduction (p = 0.04, Mann-Whitney U test).

Table 5: Secondary Outcomes

 Non-SSI complications, such as wound dehiscence or pneumonia, occurred in 2 patients (4%) in the PAP group and 3 (6%) in the control group, with no significant difference (p = 0.68, chi-square test).

Adverse events related to antibiotic prophylaxis were minimal (Table 6). One patient (2%) in the PAP group experienced a mild allergic reaction (pruritus), which resolved spontaneously, while no such events occurred in the control group. No cases of Clostridium difficile infection were observed in either group.

Table 6: Adverse Events Related to Antibiotic Prophylaxis

This study highlights the significant role of preoperative antibiotic prophylaxis (PAP) with Ceftriaxone in reducing surgical site infections (SSIs) in abdominal surgery. The findings align with a body of evidence that supports the efficacy of PAP in various surgical disciplines. Specifically, the study reports a reduction in SSI incidence from 20% in the control group to 10% in the PAP group (p = 0.037), a difference that is statistically significant. This 50% relative risk reduction in SSI aligns with the outcomes of previous studies. A meta-analysis by de Jonge et al. (2017) demonstrated a 50%–70% reduction in SSI risk with prophylaxis, reinforcing the robustness of PAP's effectiveness in preventing infections across various types of surgery, including abdominal procedures [7].

The absolute risk reduction of 10% in this study underscores the clinical relevance of PAP, especially in settings with limited resources such as Government Medical College, Srikakulam, where infection control is particularly crucial. Similar findings were reported by some studies who compared prophylactic antibiotic administration in emergency versus elective surgeries, highlighting the effectiveness of PAP in preventing infections even in resource-constrained environments [8].

In terms of infection types, the predominance of superficial SSIs (66.7%) over deep infections, with no significant difference in subtype distribution between the two groups (p = 0.15), mirrors the findings from other studies. This is consistent with what some studies observed in soft tissue procedures, where superficial infections were more common than deep infections [9]. Moreover, the microbiological profile of the SSIs in this study aligns with typical abdominal surgery flora, with Escherichia coli (46.7%) and Staphylococcus aureus (26.7%) being the most common pathogens. This finding is consistent with global guidelines, such as those provided by the World Health Organization (2018), which stress the importance of managing common pathogens in abdominal surgery through appropriate antibiotic prophylaxis [10].

One of the more reassuring findings from this study is the lack of any significant impact of PAP on the microbial ecology. The absence of a difference in pathogen profiles (p = 0.72) or methicillin-resistant Staphylococcus aureus (MRSA) incidence suggests that the use of Ceftriaxone did not contribute to the development of antibiotic-resistant pathogens. This finding is significant in light of global concerns over antibiotic resistance. Tzovaras G emphasized the importance of balancing the benefits of PAP with the potential risks associated with resistance, especially when administering antibiotics in surgical settings [11].

The study also notes a secondary benefit of PAP: a reduced median hospital stay of 6 days compared to 7 days in the control group (p = 0.04), potentially lowering both healthcare costs and resource utilization. This finding is consistent with recent studies which examined the cost-effectiveness of surgical antimicrobial prophylaxis in pediatric abdominal surgery, further supporting the economic benefits of PAP in reducing both infection rates and the length of hospital stays [12]. However, the study found no significant difference in non-SSI complications (p = 0.68), suggesting that while PAP reduces the incidence of SSIs, it does not impact other postoperative complications.

Regarding safety, the study reports only one mild allergic reaction in the PAP group, with no cases of Clostridium difficile infection. This finding supports the safety profile of PAP, as reported in previous studies, which found low adverse event rates associated with the use of Ceftriaxone for prophylaxis [13]. Furthermore, some studies reviewed guidelines for antibiotic prophylaxis in abdominal surgery and concluded that Ceftriaxone remains a safe and effective choice in preventing SSIs in a variety of surgical contexts, with a very low risk of adverse events [14].

Limitations include the modest sample size (n=100), single-center design, and lack of long-term follow-up beyond 30 days, which may limit generalizability. Variability in surgical techniques or patient comorbidities, though minimized by randomization, could also influence outcomes. Future multicenter studies with larger cohorts and resistance monitoring are warranted.

This study confirms that preoperative antibiotic prophylaxis with Ceftriaxone significantly reduces surgical site infections (10% vs. 20%, p = 0.037) and hospital stay (6 vs. 7 days, p = 0.04) in abdominal surgery patients with a 50% relative risk reduction. The intervention proved safe, with only one mild allergic reaction and no Clostridium difficile infections. These findings support PAP’s routine implementation in similar resource-limited settings to enhance patient outcomes and reduce healthcare burdens. However, larger multicenter studies are needed to validate these results and monitor antibiotic resistance, ensuring sustained efficacy in infection prevention.

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