European Journal of Cardiovascular Medicine

Surgical Site Infections (SSIs) are among the most frequent healthcare-associated infections, particularly following abdominal procedures, posing a substantial burden on surgical outcomes and healthcare resources worldwide (1). The World Health Organization reports that SSIs account for up to 20% of all hospital-acquired infections in low- and middle-income countries, leading to increased morbidity, longer hospital stays, and higher treatment costs (2).

Abdominal surgeries inherently carry a higher risk of infection due to the proximity to the gastrointestinal tract and the potential for contamination during the procedure. Several patient-related and procedural risk factors have been linked to the development of SSIs. These include age, diabetes mellitus, nutritional status, immunosuppression, duration and type of surgery, wound classification, and adherence to sterile techniques (3,4).

Despite advancements in surgical techniques and antibiotic prophylaxis, the incidence of SSIs remains a significant concern, especially in emergency surgical settings and in resource-limited environments. Timely identification of modifiable risk factors and implementation of evidence-based preventive measures are critical in reducing the incidence of SSIs and improving patient outcomes (5,6).

This study aims to assess the incidence of SSIs in patients undergoing abdominal surgeries and to evaluate the associated risk factors contributing to their development.

This prospective observational study was conducted in the Department of General Surgery at a tertiary care hospital over a period of six months. Written informed consent was taken from all participants.

A total of 150 patients who underwent abdominal surgeries—both elective and emergency—were included in the study based on inclusion and exclusion criteria. Inclusion criteria comprised patients aged 18 years and above undergoing open abdominal surgeries. Patients with pre-existing infections, those on immunosuppressive therapy, or with incomplete follow-up were excluded.

Preoperative data were collected, including patient demographics, comorbidities (such as diabetes, hypertension), nutritional status, and history of smoking or alcohol use. Intraoperative variables like type of surgery (elective or emergency), wound classification (clean, clean-contaminated, contaminated, dirty), duration of surgery, and use of antibiotic prophylaxis were documented.

Postoperative monitoring was done daily for signs of surgical site infections including redness, swelling, pain, discharge, and fever. Wound cultures were taken from suspected infections and sent for microbiological examination. Patients were followed up for 30 days post-surgery, either during hospitalization or on an outpatient basis.

Surgical site infections were classified according to the Centers for Disease Control and Prevention (CDC) criteria. Data were entered into Microsoft Excel and analyzed using SPSS version 25.0. Chi-square test and logistic regression analysis were employed to identify statistically significant risk factors, with a p-value <0.05 considered significant.

Out of the 150 patients included in the study, 92 (61.3%) were male and 58 (38.7%) were female. The mean age of the participants was 45.6 ± 12.4 years. Surgical Site Infections (SSIs) were observed in 27 patients, accounting for an overall incidence of 18%.

The incidence of SSIs was higher among patients who underwent emergency surgeries (25%) compared to elective procedures (12%) (Table 1). A statistically significant association was found between emergency surgery and the occurrence of SSIs (p=0.04).

Comorbid conditions such as diabetes mellitus were present in 36 patients, of whom 12 (33.3%) developed SSIs. Among non-diabetic patients, only 15 (12.5%) had SSIs, indicating a significant correlation between diabetes and infection risk (p=0.01) (Table 2).

The rate of SSIs increased with the duration of surgery. Procedures lasting more than 2 hours had an SSI rate of 26.3%, while surgeries under 2 hours showed a rate of 11.1% (Table 3). This difference was statistically significant (p=0.03).

Based on wound classification, dirty wounds had the highest SSI rate (36%), followed by contaminated (28%), clean-contaminated (12%), and clean wounds (4%) (Table 4).

The relationship between wound type and SSI occurrence was also significant (p=0.002).

The most commonly isolated pathogen in culture-positive SSIs was Staphylococcus aureus (44.4%), followed by Escherichia coli (29.6%) and Pseudomonas aeruginosa (18.5%) (Table 5).

Table 1: Incidence of SSIs Based on Type of Surgery

Table 2: SSIs in Relation to Diabetes Mellitus

Table 3: SSIs and Duration of Surgery

Table 4: SSIs Based on Wound Classification

Table 5: Distribution of Bacterial Pathogens Isolated from SSIs

The present study highlights a significant burden of Surgical Site Infections (SSIs) following abdominal surgeries, with an overall incidence rate of 18%. This figure aligns with similar studies conducted in developing countries, where the SSI rate ranges between 10–25% depending on hospital practices, patient population, and infection control measures (1,2).

Our findings revealed that emergency surgeries were associated with a higher risk of SSIs compared to elective procedures. This observation supports previous literature indicating that emergency operations often lack optimal preoperative preparation and are performed under less controlled conditions, contributing to a greater risk of infection (3,4).

Diabetes mellitus was significantly associated with increased susceptibility to SSIs in this study. Impaired wound healing and altered immune response in diabetic patients are well-documented risk factors for postoperative infections (5,6). These results are consistent with those reported by Anvikar et al. and others, who identified diabetes as an independent predictor of SSIs (7,8).

Duration of surgery was another significant variable, with prolonged operative time (>2 hours) increasing the likelihood of infection. Longer surgical exposure potentially increases the risk of microbial contamination and tissue trauma, as supported by earlier research (9,10).

Wound classification played a crucial role in determining infection rates. Dirty and contaminated wounds had significantly higher SSI rates, which is consistent with the CDC’s classification system correlating higher contamination levels with increased infection risk (11,12).

The predominant microorganism isolated from infected wounds was Staphylococcus aureus, which agrees with global trends in SSI microbiology (13). The emergence of Escherichia coli and Pseudomonas aeruginosa as common isolates underscores the need for periodic surveillance of pathogen profiles and sensitivity patterns to guide empirical antibiotic therapy (14,15).

This study reinforces the importance of preoperative optimization, especially for patients with comorbidities like diabetes, adherence to infection control protocols, and the judicious use of prophylactic antibiotics. Timely recognition and classification of wounds, appropriate surgical planning, and limiting operative duration may collectively reduce SSI rates and improve surgical outcomes.

Limitations of the study include a relatively short follow-up period (30 days) and single-center design, which may affect the generalizability of the findings. Further multicenter studies with larger sample sizes and extended follow-up are recommended to validate and expand upon these results.

Surgical site infections remain a significant complication following abdominal surgeries, with factors such as emergency procedures, diabetes, prolonged operative time, and contaminated wounds contributing notably to their incidence. Early identification and management of these risk factors are essential to improve patient outcomes and reduce postoperative morbidity.

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