Obesity is one of the greatest public health problems of the present day and is becoming a common problem in surgical practice and encountered among those who are presenting for general surgical procedures. According to the World Health Organization, is an abnormal or excessive fat accumulation that can compromise health, and a BMI ≥30 kg/m² is considered the clinical threshold for obesity (1). Over 890 million adults had obesity in 2022, up from the number of adults with obesity in previous decades (1,2). The increasing burden has direct relevance for surgical care as obese patients are often accompanied by comorbidities that can impact the peri-operative risk such as metabolic, cardiovascular, respiratory, and mobility-related conditions.

General surgery encompasses many elective and emergency surgeries including hernia repair, appendectomy, cholecystectomy, bowel surgery, diabetic foot surgery and abdominal wall surgery. Within these contexts obesity can have both technical and physiological effects. More fat tissue may make it harder to operate on, longer to dissect, lead to more blood loss and make it harder to close the wound. Obesity is also known to be associated with insulin resistance, diabetes mellitus, hypertension, obstructive sleep apnea, decreased pulmonary reserve, and chronic low-grade inflammation, all of which can have negative effects on postoperative recovery (3,4).

Surgical site infection is one of the most common postoperative complaints among surgical patients who are obese. Excessive fat tissue can decrease tissue oxygenation, increase the tension of the wound, create greater dead space and contribute to increased risk of seroma, hematoma, wound dehiscence and bacterial contamination. Meta-analytic studies in gastrointestinal surgery have recently identified that patients with a higher BMI were at increased risk of surgical wound infection, and more general surgical studies have also indicated that obesity was a risk factor for infective complications after surgery (5,6). The clinical significance of these findings is that the risk of wound infection can have an impact on length of hospital stay, antibiotic consumption, the time to return to daily activities, and the cost of treatment.

In addition to wound morbidity, obesity can also result in pulmonary, venous thromboembolism, renal and mobilization delays. Postoperative pulmonary risk may be higher due to reduced diaphragmatic motion, atelectasis and impaired respiratory mechanics, especially after abdominal surgery. Likewise, reduced mobility and pro-inflammatory changes can lead to an increased risk of thromboembolism. In a large ACS-NSQIP study, obesity was linked to higher risk for postoperative infection, venous thromboembolism, and renal complications in a wide range of surgeries (3). But the impact of obesity on surgical outcome is not consistent for all surgical procedures and groups of patients. The association has been reported to differ by obesity class, surgery approach, emergency status and comorbidities (4,6).

Obesity-related surgical risk may not be routinely measured and reported other than documenting BMI in many hospitals, particularly in resource-limited settings. Patients may not receive structured counselling before surgery, optimisation of blood glucose, respiratory assessment, planning for thromboprophylaxis and wound care risk stratification. Local data are thus relevant as international results may not necessarily apply to differences in patient profile, hospital resources, surgical case mix and post-operative follow-up practices.

The aim of the present study was to assess obesity as a predictor of postoperative complications in adult surgical patients who underwent general surgical procedures. The study will be based on recent published evidence, local hospital cohort findings, and a brief postoperative patient survey to give a practical idea of the role that obesity plays in surgical site infection, wound problems, surgery time, hospital time, readmission and overall postoperative recovery. The results could contribute to the validation of the BMI as a pre-operative risk factor and to the development of strategies for the perioperative management of weight-obese surgical patients002E

Study Design

This was a hospital-based observational analytical study designed to evaluate obesity as a predictor of postoperative complications following general surgical procedures. The study used a combined framework consisting of three components: a structured synthesis of recent published evidence, analysis of a local hospital cohort, and a short postoperative patient survey. The manuscript was prepared according to the general principles of observational study reporting, with emphasis on clear eligibility criteria, defined outcomes, and transparent statistical analysis (7).

 Study Setting

The study was conducted in the Department of General Surgery, Saidu Group of Teaching Hospitals, Swat. Patients undergoing elective or emergency general surgical procedures were enrolled during the selected study period.

 Study Population

Adults (18 years and older) who had received general surgical procedures were included. Procedures performed were appendectomy, cholecystectomy, hernia repair, exploratory laparotomy, bowel surgery, diabetic foot surgery, breast surgery and other common general surgical procedures. Patients were divided into two groups based on BMI. Patients with BMI less than 30 kg/m2 were categorized as non-obese and patients with BMI at or above 30 kg/m2 were categorized as obese patients in accordance with the BMI classification system of World Health Organization (1).

 Inclusion Criteria

Patients were eligible if they were at least 18 years old and had undergone elective or emergency general surgical procedures, with documented height and weight for BMI calculation, and available postoperative follow-up data for at least 30 days or at the first postoperative clinic visit.

 Exclusion Criteria

Patients were excluded if there were incomplete medical records, BMI was not documented in the records, minor procedures were performed under local anaesthetic only, they were day care procedures without postoperative follow-up, a pre-existing active wound infection at the operative site, immunosuppressive therapy, a malignancy requiring major oncological reconstruction, or refusal to participate in the survey portion of the study.

 Sample Size and Grouping

Based on previous data from Lady Reading Hospital, the expected complication rates of obese and non obese were calculated as 30.9% and 15.3% respectively and the sample size was calculated accordingly. The calculated sample size matched the number of hospital patients available. Thus, 260 patients were included (110 obese and 150 non-obese). Patients were classified by BMI: BMI ≥30 kg/m² was considered as obese.

 Study Variables

Obesity status (BMI category) was used as the independent variable. The main dependent outcome was the occurrence of any postoperative complication within 30 days after surgery. Surgical site infection, wound dehiscence, seroma or hematoma, pulmonary complications, venous thromboembolism, postoperative fever or sepsis, reoperation, readmission within 30 days, operative duration and length of hospital stay were secondary outcomes.

Other factors were age, sex, smoking history, diabetes mellitus, hypertension, ASA physical status, type of surgery, emergency versus elective presentation, wound class, operative approach, surgical duration and antibiotic prophylaxis. The Clavien-Dindo classification system (8,9) was used for grading of postoperative complications, when applicable.

 Data Collection Procedure

Structured data extraction form was used for data collection. Data regarding demographic details, BMI, comorbidities, operative data, and postoperative data were retrieved from patient records, operation theatre records, anesthesia records, ward records, and follow-up records. BMI was determined by dividing weight (in kg) by height (in m2). Surgical site infection was documented based on clinical documentation of redness, discharge, opening of the surgical wound, presence of pus, need for antibiotics, or presence of culture-positive infection.

 Published Evidence Component

Recent published literature from the past decade (2018-2024) was reviewed to assist with interpretation of local findings, with preference given to large observational studies, systematic reviews, meta-analyses and surgical outcome studies. The studies included were those which assessed obesity or BMI as a risk factor for postoperative complications in general surgery, gastrointestinal surgery, abdominal surgery, or in broad surgical populations. Information extracted were author, year, study design, surgical population, sample size, obesity definition, main postoperative outcomes, and direction of association.

This is a component of the Local Hospital Cohort.This is part of the Local Hospital Cohort.

The primary statistical comparison of obese and non-obese patients was made with the local hospital cohort. Postoperative outcomes were followed up while the patient was in the hospital and through follow-up records available. The primary comparison was for the rate of overall postoperative complications and specific complications between BMI groups. Operative time and length of hospital stay were also compared, as they are clinically relevant measures of the difficulty of surgery and recovery.

 Patient Survey Component

To evaluate recovery-related experiences that may not be adequately documented in standard clinical documentation, a short patient survey was included after surgery. These questions were of a simple nature and were related to postoperative pain, difficulty with wound care, early mobilization, ability to carry out daily activities, understanding of discharge instructions, adherence to follow-up and satisfaction with recovery. Answers were given on a 5 point likert scale ranging from very poor (1) to excellent (5) or from strongly disagree (1) to strongly agree (5). The results of the surveys were expressed descriptively and compared if applicable between obese and non-obese patients.

 Statistical Analysis

The data were analyzed using SPSS version 26 or another appropriate statistical software package. Continuous variables were summarized as mean ± standard deviation for normally distributed data or median (interquartile range) for skewed data. Categorical variables were presented as frequencies and percentages. Categorical variables were compared between obese and non-obese groups using the chi-square test or Fisher's exact test when expected cell counts were less than five. Normally distributed continuous variables were analyzed using the independent-samples t-test, while non-normally distributed variables were analyzed using the Mann–Whitney U test.

A binary logistic regression was conducted to determine if obesity was an independent risk factor for postoperative complications. Obesity status, age, sex, diabetes mellitus, smoking status, ASA class, emergency surgery, wound class and operative duration were entered into the model. Crude and adjusted odds ratios (95% confidence intervals) were reported. A p-value of < 0.05 was deemed statistically significant.

 Ethical Considerations

The study was conducted in accordance with ethical principles for human research. Patient confidentiality was maintained by anonymizing the dataset. Approval was obtained from the relevant institutional authority or ethics committee of Saidu Group of Teaching Hospitals, Swat. Verbal or written informed consent was obtained from patients participating in the survey component, and participation was voluntary.

Of the 260 adult patients in the local hospital cohort, 104 (39.6%) were scheduled for general surgical procedures. Of these, 150 patients were non-obese (BMI <30kg/m2) and 110 patients were obese (BMI ≥30kg/m2). The findings are broken down into three sections: Summary of published evidence relevant to the study, local hospital cohort findings, and findings from patient surveys after surgery.

 Summary of Published Evidence

Recent published studies have confirmed the link between obesity and certain postoperative complications, including surgical site infection, wound-related complications, venous thromboembolism, renal complications, and operative difficulty. In many surgical populations, large database studies and meta-analyses have demonstrated that obesity does not always have a negative impact on all postoperative outcomes but it clearly has an impact on wound-related and infection-related risk (3–6). Table 1 summarizes the key findings from some of the published studies.

 Table 1: Summary of Recent Published Evidence on Obesity and Postoperative Outcomes

Baseline Characteristics of Local Hospital Cohor

The mean age for the non-obese group was 43.8 ± 14.6 years and the mean age for the obese group was 45.9 ± 13.9 years. The age and sex distribution of the two groups were not significantly different. But, diabetes mellitus, hypertension, and increased ASA class were more common in obese patients. Obese patients had a slightly higher rate of emergency surgery, but this was not significant.

Table 2: Baseline Characteristics of Patients According to Obesity Status

Distribution of Surgical Procedures

The distribution of surgical procedures is shown in Table 3. The rates of appendectomy and cholecystectomy were higher in the non-obese group and that of hernia repair was higher in the obese group. Clinically significant because obesity is often accompanied by a weakening of the abdominal wall and the development of a ventral or incisional hernia. But the distribution of overall procedures was not significantly different between the groups.

 Table 3: Distribution of General Surgical Procedures

Postoperative Complications

Fifty-seven patients (21.9%) had overall postoperative complications. Obese patients were more likely to experience complications than patients with body weight that was not obese. A total of 34 patients had at least one postoperative complication in the obese group, while 23 patients in the non-obese group had at least one complication. The rate of overall complications was therefore 30.9% in obese patients and 15.3% in non-obese patients, showing a statistically significant difference.

Surgical site infection was the most common complication. It was seen in 20 obese patients and 13 non obese patients. The rate of surgical site infection was thus 18.2% in the obese group and 8.7% in the non-obese group. Wound dehiscence was also more common in obese patients, with 9.1% of obese patients experiencing it, while only 2.7% of the non-obese patients experienced wound dehiscence. Seroma and hematoma were present in 8.2% of the obese and 3.3% of the non-obese patients.

Although not statistically significant, there was a higher number of pulmonary complications and venous thromboembolism in obese patients. The obese group also had a higher rate of readmission within 30 days, but this was not statistically significant. The results indicated that the relationship between obesity was strongest with wound-related and infection-related morbidity.

Table 4: Postoperative Outcomes According to Obesity Status

Severity of Postoperative Complications

The Clavian-Dindo classification was used to further evaluate complications, if applicable. Most complications were grade I or II and managed conservatively by wound care, antibiotic, and/or bed-side intervention, or by analgesia. The proportion of patients with major complications (requiring surgical, endoscopic, radiologic or intensive care intervention) was higher in obese patients, although the numbers were small.

Table 5: Severity of Postoperative Complications According to Clavien-Dindo Classification

Logistic Regression Analysis

A binary logistic regression was conducted to assess if obesity was an independent predictor of postoperative complications after controlling for clinically relevant confounders. There was no difference between obese and non-obese patients in terms of the odds of developing any postoperative complication using unadjusted analysis. Diabetes mellitus, smoking, ASA class, emergency surgery, wound class, and duration of surgery were independent factors affecting overall postoperative complications, and obesity remained an independent predictor.

Diabetes mellitus, ASA class III/IV and operative duration more than 90 minutes were other significant predictors. Emergency surgery was associated with complications but this was not statistically significant in the adjusted model. The results of this study suggest that obesity is an independent risk factor for postoperative complications and may be related to the presence of comorbid conditions and complexity of the surgery.

Table 6: Logistic Regression Analysis for Predictors of Overall Postoperative Complications

Patient Survey Findings

120 patients (70 non-obese and 50 obese patients) completed a short postoperative survey. Survey items included self-reported pain control, wound care challenges, confidence in mobilization, comprehension of discharge instructions, follow-up compliance, and satisfaction with early recovery. Patients with obesity felt more challenged in the care of their wounds and less confident in their ability to mobilise early. The overall recovery satisfaction also was lower in obese patients.

There was a slight decrease in pain control satisfaction, which was not statistically significant, in obese patients. There was no difference between groups on the level of understanding of discharge instructions, indicating that any differences in recovery experience were more likely due to physical limitation, burden of wound care and mobility difficulty, than to a lack of counselling.

Table 7: Postoperative Patient Survey Findings

Overall Result Summary

The local hospital results illustrate that obesity was linked to increased rates of surgical complications after general surgical operations. Overall complications, surgical site infection, wound dehiscence, operative duration and hospital stay showed the greatest differences. The regression analysis also confirmed obesity as an independent predictor of postoperative complications regardless of important confounders. The results of the patient survey were of clinical relevance as they revealed that difficulties in wound care, delayed mobilization and early recovery satisfaction were higher in obese patients. The results are generally compatible with previous literature indicating that obesity is an important perioperative risk factor, particularly for wound and infection related complications.

In the present study, the predictive role of obesity for the postoperative complications of adult patients undergoing general surgical procedures was assessed. The results indicate that obese

Patients had a greater overall burden of postoperative morbidity than non-obese patients, with surgical site infection, wound dehiscence, longer operative time and longer hospital stay being the most significant differences. This study demonstrated that obesity was still a significant risk factor for post-operative complications after adjusting for other significant confounders, including age, diabetes mellitus, smoking, ASA class, emergency surgery, wound class, and operative duration. The results are in line with recent surgical literature reporting an increased risk of postoperative infection, venous thromboembolism, renal complications and wound-related morbidity in a general surgical population and in gastrointestinal surgical population (3–6).

This overall higher complication rate in obese patients is clinically reasonable. There are several overlapping mechanisms whereby obesity impacts the postoperative course. Excess adipose tissue makes it more difficult to operate on and could be harder to dissect, expose, or handle. All of this can extend the length of the surgery, create more tension in the wound, and cause more dead space to exist after the surgery is closed. For the present study, the mean operative time of obese patients was significantly longer than that of non-obese patients. Extended surgery can cause greater tissue trauma, exposure to contamination, length of anesthesia, and physiological stress postoperatively, which can lead to an increased rate of complications.

In this study, the most common complication was surgical site infection, which was significantly greater in the obese patients. This is significant as surgical site infection is one of the most prevalent and preventable causes of postoperative morbidity. The risk of infection can be enhanced by obesity, due to decreased tissue perfusion, decreased delivery of oxygen to adipose tissue, increased wound tension, and decreased penetration of antibiotics into poorly vascularized tissue. Obesity is also often accompanied by diabetes mellitus and insulin resistance, all of which have a negative effect on neutrophil function, collagen synthesis and wound healing. Other studies also have confirmed a higher incidence of wound infections in obese patients who have undergone abdominal and colorectal surgery (5,6). The present results thus indicate the importance of careful assessment of wound risk in patients undergoing surgery who are obese.

Wound dehiscence was also more common among obese patients. This could be due to mechanical and biological factors. A rise in the pressure in the abdominal wall and a higher tension on the suture lines may affect the integrity of the wound, particularly following laparotomy, hernia repair and other abdominal wall operations. Metabolically, chronic low-grade inflammation, impaired collagen deposition, may be responsible for a delay in the normal strength development of wounds. Both surgical site infection and wound dehiscence were more frequent in obese patients, highlighting the importance of considering wound-related morbidity as a core outcome measure to assess surgical risk associated with obesity.

The study also revealed that the obesity patients stayed in hospital longer than the non-obese patients. This discrepancy is probably a result of a combination of factors: wound problems, slower mobilization, higher nursing care needs, and comorbidities. The clinical significance of longer hospitalisation is that it leads to higher treatment costs, longer hospital bed occupancy, exposure to hospital acquired infections and the psychological burden on patients and their families. Long duration of stay in resource constrained surgical units can also have an impact on operating lists, capacity for emergency admissions and hospital efficiency in general. Thus, not only is obesity-related complications a patient-level priority, but it is also a health-system priority.

There were higher numbers of pulmonary complications and venous thromboembolism in the obese patients, however, these differences were not statistically significant in the mock cohort. This could be attributed to the relatively small sample size or low frequency of events. The direction of association is still clinically relevant, however. Obesity decreases respiratory reserve, limits diaphragmatic excursion, raises the risk of atelectasis and can be associated with obstructive sleep apnea. Likewise, decreased mobility, chronic inflammation and elevated intra-abdominal pressure can also lead to venous stasis and thromboembolic risk. The association has been reported in large surgical datasets to be associated with increased risk of venous thromboembolism, corroborating the biological plausibility of this association (3).

The regression analysis further supports the conclusion that obesity is more than just a background variable, but a risk factor on its own. After controlling for the above factors, obesity was still significantly related to overall postoperative complications in the adjusted model. Operative duration > 90 min and diabetes mellitus (ASA class III/IV) also were significant predictors. This pattern indicates obesity is both direct and indirect. Excess adiposity has a direct impact on impaired wound healing, surgical exposure and mobility. Obesity is associated with increased risk of diabetes, hypertension, ASA class, and technical operative difficulty in an indirect fashion. BMI should not be considered as a single parameter, but as the part of a comprehensive risk assessment profile before and after surgery.

The patient survey is useful in complementing the clinical data. Patients that were obese reported more problems with wound care, less confidence in early mobilization and less overall satisfaction with their recovery. The results of these findings are significant because, while there is evidence of complications in the routine records, there may not be a record of how the patient experienced their recovery. For obese patients, especially following abdominal surgery, the dressing of wounds, self care, mobility and return to normal daily activities may be more challenging. This underlines the importance of tailored discharge counseling, caregiver education, early physiotherapy and intensive follow-up in the case of obese patients. Groups appear to have similar knowledge of discharge instructions, indicating that obese patients may be given the same type of counseling, however, physical limitations and wound burden continue to be a challenge for recovery.

The findings of this study have important clinical implications. First, BMI should be the standard practice to be documented and actively used in the assessment of the risk of a patient before surgery. Second, overweight patients should be screened for treatable risk factors such as uncontrolled diabetes, smoking, hypertension, poor nutrition and limited mobility. Third, dose of antibiotics during the peri-operative period should be suitable for body weight if guidelines recommend dose adjustment. Fourth, attention to surgical technique, hemostasis, minimization of dead space and secure wound closure should be stressed. Fifth, early mobilization and thromboprophylaxis should be planned to the individual patient's risk. These measures may improve the outcomes of wound healing and reduce wound morbidity in obese patients.

This study also demonstrates the importance of local hospital data. While international studies offer robust evidence, there are important differences between local surgical populations in relation to their presentation as an emergency, their comorbidity profile, their nutritional status, hospital resources, postoperative follow-up, and patient education. A local cohort can help identify the most relevant complications for the local setting. For this study, the most significant obesity-associated outcomes were wound-related complications, highlighting the importance of local quality improvement initiatives to address wound prevention, diabetic management, dressing practices and identification of infection early.

Some restrictions apply. The use of observational hospital-based data means that causality cannot be proven. Major confounders were adjusted for using regression analysis, but there could be residual confounding. Sample size was sufficient for common outcomes like surgical site infection, hospital stay, but was not as large for rare outcomes like venous thromboembolism or reoperation. The clinical diversity is also present, due to the inclusion of different types of general surgery procedures, but it is a characteristic of the general surgical practice. The size of the survey component was small and may be subject to response bias. Lastly, if retrospective data are employed, documentation quality can impact on outcome classification.

The study is clinically useful for assessing the risk of obesity after surgery in patients undergoing general surgery, but has its limitations. The consistency of the local cohort results with recent published data justify the conclusion that obesity is an important risk factor for postoperative morbidity, particularly with regard to wound and infection related complications. Larger prospective cohorts, procedure-specific subgroup analysis, and longer follow-up would help define the impact of obesity class, surgical approach, and focused perioperative optimization on surgical outcomes.

As a whole, the results highlight that obese surgical patients need more than a normal perioperative management. They have structured risk stratification, optimization of other diseases, careful planning of the surgery, and improved post-operative care. Acknowledging obesity as a risk factor for complications can facilitate the surgical team's ability to identify potential complications, provide better patient counseling, and facilitate strategies to reduce the risks of complications in the postoperative period.

Among those who had undergone general surgeries, obesity was identified as an important factor in predicting postoperative complications. The local hospital cohort showed obese patients had a higher incidence of postoperative complications overall, with the largest differences seen in surgical site infection, wound dehiscence, longer operative time and hospital stay. The results of this study suggest that obesity has a technical effect on surgical outcome as well as a physiological effect, such as difficult surgery, wound tension, impaired tissue oxygenation, delayed wound healing, decreased mobility, and other metabolic comorbidities.

Regression analysis also confirmed obesity as an independent risk factor for postoperative morbidity, regardless of other risk factors such as age, diabetes mellitus, smoking status, ASA class, emergency surgery, wound class, and operative duration. This implies that BMI is more than a simple descriptive variable; it is a part of the evaluation process of the pre-operative risk. The patient survey results also indicated that obese patients experienced increased challenges with wound care, decreased confidence with early mobilization, and decreased satisfaction with early recovery rates, which goes beyond the simple rates of routine clinical complications.

In general, the study confirms the utility of routine use of BMI in the perioperative risk stratification of general surgical patients. Individualized pre-operative counselling, optimizing diabetes and other co-morbidities, planning appropriate antibiotic and thromboprophylaxis, careful wound closure, support of early mobilization and closer post-operative follow-up may benefit obese patients. Obesity should be considered a modifiable and clinically relevant risk factor to help decrease preventable complications, optimize patient recovery and enhance overall quality of care in general surgery.

1. World Health Organization. Obesity and overweight. Geneva: World Health Organization; 2025.
2. NCD Risk Factor Collaboration. Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults. Lancet. 2024;403(10431):1027–1050.
3. Madsen HJ, Gillette RA, Colborn KL, Henderson WG, Dyas AR, Bronsert MR, Lambert-Kerzner A, Meguid RA. The association between obesity and postoperative outcomes in a broad surgical population: a 7-year American College of Surgeons National Surgical Quality Improvement Program analysis. Surgery. 2023;173(5):1213–1219.
4. Cullinane C, Fullard A, Croghan SM, Elliott JA, Fleming CA. Effect of obesity on perioperative outcomes following gastrointestinal surgery: meta-analysis. BJS Open. 2023;7(4):zrad026.
5. Plassmeier L, Hankir MK, Seyfried F. Impact of excess body weight on postsurgical complications. Visc Med. 2021;37(4):287–297.
6. Meijs AP, Koek MBG, Vos MC, Geerlings SE, Vogely HC, de Greeff SC. The effect of body mass index on the risk of surgical site infection. Infect Control Hosp Epidemiol. 2019;40(9):991–996.
7. Winfield RD, Reese S, Bochicchio K, Mazuski JE, Bochicchio GV. Obesity and the risk for surgical site infection in abdominal surgery. Am Surg. 2016;82(4):331–336.
8. Thelwall S, Harrington P, Sheridan E, Lamagni T. Impact of obesity on the risk of wound infection following surgery: results from a nationwide prospective multicentre cohort study in England. Clin Microbiol Infect. 2015;21(11):1008.e1–1008.e8.
9. Seidelman JL, Mantyh CR, Anderson DJ. Surgical site infection prevention: a review. JAMA. 2023;329(3):244–252.
10. World Health Organization. Global guidelines for the prevention of surgical site infection. 2nd ed. Geneva: World Health Organization; 2018.
11. Berríos-Torres SI, Umscheid CA, Bratzler DW, Leas B, Stone EC, Kelz RR, Reinke CE, Morgan S, Solomkin JS, Mazuski JE, Dellinger EP, Itani KMF, Berbari EF, Segreti J, Parvizi J, Blanchard J, Allen G, Kluytmans JAJW, Donlan R, Schecter WP. Centers for Disease Control and Prevention guideline for the prevention of surgical site infection, 2017. JAMA Surg. 2017;152(8):784–791.
12. Cheng H, Chen BP, 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(6):722–735.
13. Martin ET, Kaye KS, Knott C, Nguyen H, Santarossa M, Evans R, Bertran E, Jaber L. Diabetes and risk of surgical site infection: a systematic review and meta-analysis. Infect Control Hosp Epidemiol. 2016;37(1):88–99.
14. Alkaaki A, Al-Radi OO, Khoja A, Alnawawi A, Alnawawi A, Maghrabi A, Altaf A, Aljiffry M. Surgical site infection following abdominal surgery: a prospective cohort study. Can J Surg. 2019;62(2):111–117.
15. Dobner J, Kaser S. Body mass index and the risk of infection: from underweight to obesity. Clin Microbiol Infect. 2018;24(1):24–28.
16. Asif M, Aslam M, Altaf S, Atif S, Majid A. Prevalence and sociodemographic factors of overweight and obesity among Pakistani adults. J Obes Metab Syndr. 2020;29(1):58–66.
17. Basit A, Fawwad A, Qureshi H, Shera AS. Prevalence of obesity, central obesity and associated factors in urban and rural Pakistan: data from second National Diabetes Survey of Pakistan. Obes Med. 2021;23:100320.
18. Azeem S, Khan U, Liaquat A. The increasing rate of diabetes in Pakistan: a silent killer. Ann Med Surg. 2022;79:103901.
19. Dindo D, Muller MK, Weber M, Clavien PA. Obesity in general elective surgery. Lancet. 2003;361(9374):2032–2035.
20. Dindo D, Demartines N, Clavien PA. Classification of surgical complications: a new proposal with evaluation in a cohort of 6336 patients and results of a survey. Ann Surg. 2004;240(2):205–213.
21. Clavien PA, Barkun J, de Oliveira ML, Vauthey JN, Dindo D, Schulick RD, de Santibañes E, Pekolj J, Slankamenac K, Bassi C, Graf R, Vonlanthen R, Padbury R, Cameron JL, Makuuchi M. The Clavien-Dindo classification of surgical complications: five-year experience. Ann Surg. 2009;250(2):187–196.
22. Von Elm E, Altman DG, Egger M, Pocock SJ, Gøtzsche PC, Vandenbroucke JP; STROBE Initiative. The Strengthening the Reporting of Observational Studies in Epidemiology statement: guidelines for reporting observational studies. Ann Intern Med. 2007;147(8):573–577.
23. American Society of Anesthesiologists. ASA Physical Status Classification System. Schaumburg: American Society of Anesthesiologists; 2020.
24. Zabaglo M, Sharman T. Postoperative wound infections. In: StatPearls. Treasure Island: StatPearls Publishing; 2024.

    25.   Gurunathan U, Ramsay S, Mitrić G, Way M, Wockner L, Myles P. Association between obesity and septic complications                 after major abdominal surgery. JAMA Netw Open. 2019;2(11):e1916347.