European Journal of Cardiovascular Medicine

Postoperative Surgical Site Infections (SSIs) remain one of the most significant complications following surgical procedures and represent a major concern in modern healthcare systems worldwide. Despite advancements in aseptic techniques, antibiotic prophylaxis, and perioperative care, SSIs continue to contribute substantially to postoperative morbidity, prolonged hospital stay, increased healthcare costs, and, in severe cases, mortality. The burden is particularly high in low- and middle-income countries where resource limitations, overcrowding, and inconsistent infection control practices further exacerbate the problem.

According to the Centers for Disease Control and Prevention (CDC), SSIs are defined as infections occurring within 30 days of surgery or within one year if an implant is placed, involving either the incision or deeper tissues. They are broadly classified into superficial incisional, deep incisional, and organ/space infections. The development of SSIs is multifactorial, involving a complex interplay between patient-related factors, microbial virulence, and surgical/environmental conditions.

Patient-related risk factors include advanced age, diabetes mellitus, obesity, malnutrition, immunosuppression, anemia, and prolonged preoperative hospital stay. Among these, diabetes and hyperglycemia have been consistently identified as strong predictors due to impaired leukocyte function and delayed wound healing. Obesity contributes to poor tissue perfusion and increased operative difficulty, while malnutrition impairs collagen synthesis and immune response.

Procedure-related factors such as duration of surgery, type of surgical procedure, emergency surgery, inadequate sterilization, and improper antibiotic prophylaxis significantly influence SSI rates. Contaminated and dirty surgeries carry a much higher risk compared to clean elective procedures. Additionally, the use of implants or prosthetic materials increases susceptibility to infection due to biofilm formation, which protects bacteria from host immunity and antibiotics.

Microbiologically, SSIs are predominantly caused by bacteria originating from the patient’s endogenous flora or the hospital environment. Gram-positive organisms such as Staphylococcus aureus, including methicillin-resistant Staphylococcus aureus (MRSA), remain the most common pathogens in clean surgical procedures. In contrast, gram-negative organisms such as Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter species are frequently isolated in abdominal and contaminated surgeries. The emergence of multidrug-resistant organisms (MDROs) has further complicated treatment strategies and increased the risk of poor outcomes.

The consequences of SSIs are clinically and economically significant. Patients with SSIs experience delayed wound healing, increased pain, prolonged hospitalization, higher readmission rates, and additional surgical interventions. From a healthcare system perspective, SSIs impose a substantial financial burden due to extended bed occupancy, additional antibiotic therapy, and increased resource utilization.

Despite being largely preventable, SSIs continue to pose a major challenge in surgical practice. Surveillance, early detection, adherence to infection control protocols, and rational antibiotic use are critical in reducing their incidence. Moreover, understanding the local microbial profile and resistance patterns is essential for formulating effective empirical antibiotic policies.

In this context, the present study aims to evaluate postoperative SSIs in a tertiary care hospital with respect to risk factors, microbiological profile, and clinical outcomes. The findings of this study are expected to contribute to improved infection control strategies, optimized antibiotic stewardship, and better postoperative care protocols.

Study Design Prospective observational study. Study Setting Department of General Surgery, tertiary care teaching hospital. Study Duration 12 months. Sample Size 200 postoperative patients. Inclusion Criteria • Patients undergoing clean, clean-contaminated, contaminated, or dirty surgeries • Age ≥ 18 years • Developed SSI within 30 days of surgery Exclusion Criteria • Pre-existing wound infection • Immunocompromised patients on chemotherapy (excluded in some analyses) • Incomplete records Data Collection • Demographic details • Comorbidities • Type and duration of surgery • Emergency vs elective procedure • Antibiotic prophylaxis • Postoperative SSI development Microbiological Analysis • Wound swab collected under aseptic precautions • Culture on blood agar and MacConkey agar • Identification by standard biochemical tests • Antibiotic sensitivity testing by Kirby-Bauer method Statistical Analysis Data analyzed using chi-square test and t-test. p < 0.05 considered significant.

1. Incidence of SSI

• Total surgeries: 200
• SSI cases: 25
• Incidence: 12.5%

2. Risk Factors

3. Microbial Profile

• MRSA detected in 12% cases
• ESBL producers in 18% cases

4. Clinical Outcomes

The present study highlights postoperative Surgical Site Infections (SSIs) as a significant contributor to postoperative morbidity in a tertiary care setting, with identifiable risk factors, distinct microbial patterns, and clinically relevant outcomes. The findings are consistent with previously published literature indicating that SSIs are multifactorial in origin, involving patient-related, procedural, and environmental determinants.

In our study, patient-related factors such as diabetes mellitus, obesity, anemia, and prolonged preoperative hospital stay were strongly associated with increased SSI incidence. This aligns with studies by Mangram et al. and Andersen et al., which emphasize impaired immunity, poor glycemic control, and reduced tissue oxygenation as key contributors to infection susceptibility. Diabetes, in particular, remains a consistently reported independent risk factor due to its adverse effects on neutrophil function and wound healing dynamics.

Among procedure-related factors, prolonged operative time and emergency surgeries were significantly associated with higher infection rates. Longer duration of surgery increases exposure of tissues to environmental pathogens, while emergency procedures often compromise preoperative optimization and aseptic preparation. These findings are in agreement with global SSI surveillance studies conducted by the CDC and WHO collaborative groups.

Microbiologically, Gram-negative organisms such as Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa were commonly isolated in abdominal surgeries, whereas Staphylococcus aureus predominated in clean surgical wounds. The emergence of multidrug-resistant organisms, particularly MRSA and ESBL-producing Enterobacteriaceae, presents a growing therapeutic challenge and underscores the importance of local antibiograms for guiding empirical therapy.

Clinically, patients with SSIs experienced prolonged hospital stays, increased requirement for intravenous antibiotics, and delayed wound healing, consistent with findings reported by Kirkland et al. and Astagneau et al. The economic burden associated with SSIs was also evident, reflecting increased healthcare costs due to additional interventions and resource utilization.

Despite these findings, the study has limitations, including its single-center design and limited sample size, which may affect generalizability. Additionally, long-term outcomes such as chronic wound complications and quality of life were not assessed.

Overall, the study reinforces the importance of strict adherence to infection prevention protocols, optimal perioperative glycemic control, appropriate antibiotic prophylaxis, and ongoing surveillance of microbial resistance patterns. Strengthening infection control practices in tertiary care hospitals can significantly reduce SSI burden and improve surgical outcomes.

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