SSIs have become a great concern in contemporary surgical practice, with a real challenge not only to patient outcomes but also to the health systems worldwide. Defined as occurring from 30 days of surgery, or within one year, in the presence of implants, SSIs represent the third most commonly reported nosocomial infection, accounting for 12–16% of all healthcare-associated infections [1]. Despite the advances of infection control practice with improved operating room ventilation, sterilization techniques, aseptic barriers, surgical technique, and effective prophylaxis including antimicrobial use, SSIs remain a major cause of morbidity, mortality, and financial burden. It is a perennial issue compounded by the increasing presentation of elderly, immunocompromised, or debilitated patients for surgery and the emergence and development of antimicrobial-resistant pathogens [2].

An infected surgical wound is one that meets any of the defined clinical criteria. The clinical criteria include purulent drainage, spontaneous wound dehiscence with drainage, positive culture for bacteria, or if the surgeon can see and feel erythema and drainage. Complications of SSIs are not limited to delayed wound healing, sepsis, wound dehiscence, hernias, and chronic disfiguring scars. All these might have a significant impact on a patient's physical and psychological states. Therefore, control of SSIs is essential to optimize postoperative care and improve overall surgical outcomes [3-4].

Among the numerous risk and disease progression factors identified for SSIs, it was lately that the technique of skin closure emerged as the main factor influencing wound complications following surgical operations. Skin closure with primary approximation describes immediate skin and subcutaneous tissue closure after exhaustive lavage of the peritoneum. It is most popularly utilized for clean-contaminated wounds [5-6].

On the other hand, there is delayed primary closure, wherein, intentionally, the wound remains open and gets dressed with saline-soaked gauze every day. Then, the wound is sutured when it appears healthy enough, due after a period of 4–7 days. That particular procedure is quite useful in cases related to contaminated or heavily colonized wounds since the microbial burden is managed effortlessly along with granulation before closing [7]. The scientific principles of these techniques have been established, yet evidence remains mixed regarding their ability to decrease rates of SSI and to enhance healing of incisions overall, particularly in class III (contaminated) and class IV (dirty or infected) abdominal surgical wounds. Some authors now champion the techniques as protective against subsequent infection, but an equal number obtain equivalent outcomes if primary closure is performed when proper control of infection should be assumed [8].

It points out the need for effective evidence-based research that can steer appropriate clinical decisions in cases such as these. This research will systematically evaluate the results of primary skin closure versus delayed primary skin closure in class III and class IV abdominal surgical wounds. This paper compares how incidences for SSIs, healing rates of wounds, and other postoperative complications occur; these can help doctors in clinics make judgments on which kind of skin closure would be safest in such high-risk wounds and how it could help ensure good patient care and better results at discharge [9-10].

This study was aimed at comparing the outcomes of primary and delayed primary skin closure techniques on class III and class IV abdominal surgical wounds with regard to their implication in surgical site infections, and allied complications post-surgery. The work designed was towards data collection that would enable systematic and thorough analysis, coupled with maintaining high standards of both clinical and scientific accuracy.

Study Design

This was a prospective, observational study evaluating and comparing the two closure techniques. The study population consisted of patients admitted for emergency laparotomies at the Department of General Surgery, DR. BRAM Hospital. The study assessed the incidence of SSIs, wound healing parameters, and associated complications in class III (contaminated) and class IV (dirty/infected) surgical wounds.

Study Population and Inclusion Criteria:

The study consisted of patients who undertook emergency laparotomy whose abdominal wounds had been graded by CDC criteria as being of class III or class IV. Only patients who were aged 18 years and above with informed consent were recruited into the study. The study excluded patients undertaking elective surgery, patients who have underlying immunosuppressive disorders, and those who have been administered antibiotics within the preceding 48 hours before surgery.

Surgical Techniques and Group Allocation

Patients were divided into two categories, depending on the method of wound closure used: primary closure or delayed primary closure. The technique of surgery was decided intraoperatively by the operating surgeon, depending upon the intraoperative findings and the degree of contamination of the wound.

• Primary Closure. This closure group had immediate closure at the end of surgery by interrupted sutures, subcuticular sutures, or staples at the discretion of the surgeon. Prior to closure, intensive lavage of the peritoneum was performed to decrease microbial counts.
• Delayed Primary Closure: In this group, the wound was initially left open following the closing of deeper layers such as fascia. The open wound was dressed on a daily basis, using gauze saturated with normal saline to solicit formation of granulation tissues. This group closed the wound with sutures or staples after an average of five days if it showed healthy granulation tissue and had no signs of infection.

Antibiotic protocol and postoperative care

All patients had received preoperative and postoperative antibiotics based on the institutional protocol. Intraoperatively, first or second generation cephalosporin  was administered, modified intraoperatively, or postoperative wound cultures. All patients undergoing delayed closure received meticulous wound care that included sterile dressing changes until definitive closure occurred.

Outcome Measures

Incidence of surgical site infections, which can be superficial, deep, or organ/space infection according to CDC criteria, was the primary outcome measure. Secondary outcomes included time to complete wound healing, duration of hospital stay, and appearance of other complications such as sepsis, wound dehiscence, or hernia formation.

Data Collection

Data collection was prospective through a combination of direct patient observation, review of medical records, and laboratory investigations. Wound cultures are obtained from all purulent or suspicious wounds in order to identify the causative pathogens and guide antibiotic therapy. Photographic documentation of wounds was done at each phase of healing to ensure consistency in the assessment.

Statistical Analysis

The data was analyzed through appropriate statistical methods that compare the outcomes of the two groups under investigation. Continuous variables, that is healing time and hospital stay, are reported as means and were compared using a Student's t-test while categorical variables, including SSI incidence, were compared by use of the chi-square test. Whereby, the p-value <0.05 is considered statistically significant. Ethical Considerations The study adheres to the ethical principles of the institution and also to the Declaration of Helsinki. All patients gave consent for participation, and patient confidentiality was upheld. Ethical clearance was conducted prior to the initiation of the study with the review board.

The study included a total of 120 patients undergoing emergency laparotomy for class III and class IV abdominal wounds. Patients were divided into two groups: 60 patients in the primary closure group and 60 in the delayed primary closure group. The demographic, clinical, and intraoperative characteristics of the two groups were comparable, ensuring a uniform baseline for comparison.

Incidence of Surgical Site Infections

The overall incidence of SSIs was significantly higher in the primary closure group (41.7%) compared to the delayed primary closure group (21.7%) (p=0.01). Among patients in the primary closure group, superficial SSIs were the most common (27%), followed by deep infections (10%) and organ/space infections (4.7%). In the delayed primary closure group, superficial SSIs were also predominant (16.7%), with no cases of deep or organ/space infections observed.

Table 1: Incidence and Classification of Surgical Site Infections

Wound Healing and Hospital Stay

The mean time to complete wound healing was significantly shorter in the delayed primary closure group (16.5 ± 3.2 days) compared to the primary closure group (22.1 ± 4.5 days, p<0.001). Additionally, patients in the delayed primary closure group had a shorter mean duration of hospital stay (12.8 ± 2.7 days) compared to the primary closure group (15.6 ± 3.4 days, p=0.002).

Table 2: Wound Healing Time and Hospital Stay

Complications
The incidence of other postoperative complications, including wound dehiscence, hernia formation, and sepsis, was higher in the primary closure group. Wound dehiscence occurred in 8 patients (13.3%) in the primary closure group, compared to 3 patients (5%) in the delayed primary closure group. Sepsis developed in 4 patients in the primary closure group, while only one case was recorded in the delayed primary closure group.

Figure 1: Comparison of Postoperative Complications in the Two Groups

This figure illustrates the comparative incidence of postoperative complications, emphasizing the higher rates of wound dehiscence and sepsis in the primary closure group.

Microbial Profile and Antibiotic Use

The most commonly isolated pathogens were Escherichia coli (35%), Klebsiella pneumoniae (25%), and Staphylococcus aureus (20%). All isolates were sensitive to cefazolin or second-generation cephalosporins, and targeted antibiotic therapy based on wound cultures resulted in effective management of SSIs.

Table 3: Microbial Profile of SSI Cases

These findings highlight the lower incidence of SSIs, shorter wound healing times, and fewer complications in patients undergoing delayed primary closure, suggesting that this method is a superior strategy for managing class III and class IV abdominal wounds.

Surgical site infections (SSIs) remain the most important challenges in abdominal surgeries, more especially in class III and IV wounds whose basic levels of contamination are high. This study evaluates the primary closure as well as delayed primary closure techniques in such wounds, with regard to the outcomes regarding incidence of SSIs, healing time of the wound, length of hospital stay, and postoperative complications. The findings highlight significant differences between the two methods, with delayed primary closure demonstrating superior outcomes in most parameters [11].

The overall incidence of SSIs was notably higher in the primary closure group compared to the delayed primary closure group. This aligns with the understanding that immediate closure of contaminated or infected wounds increases the risk of bacterial proliferation within the wound site, leading to infections. Delayed primary closure of a wound keeps it open initially, an exudate drain, and reduction of bacterial count, before closing with granulation tissue to provide a lesser chance of infection [12-13].

Healing times for wounds were much shorter in the delayed primary closure group. Probably the most important factor contributing to this was ensuring a clean and healthy wound bed at the time of closure. Healing times were significantly longer in the primary closure group, most likely related to the higher rate of SSIs and their consequences in terms of wound dehiscence and prolonged inflammation [14].

Patients with delayed primary closure also had shorter mean hospital stays. Fewer complications and shorter times to the wound healing of these patients allowed for earlier discharge and thus the potential for reduced hospital burden by this approach. Conversely, increased hospital stay lengths were observed among patients who received primary closure, due to higher rates of SSI and additional procedures such as wound drainage and secondary healing management [15-16].

The microbial profile of the SSI cases revealed that the predominant pathogens include Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus. This is in keeping with the literature, which indicates that gram-negative bacilli and gram-positive cocci are common causes of abdominal SSIs. Culture-directed antibiotic therapy was effective in the management of these infections; thus, microbiological evaluation in postoperative care remains an important intervention [17].

The complication rate of dehiscence of wound, herniation and sepsis was higher in the use of primary closure. While higher tension of closed tissue layers is viewed as one rationale, contaminants, though at a trace level, are present in closed tissues. Delayed primary wound closure resulted in minimizing risks to these complications by letting the environment of the wound be in a conducive manner to healing, hence reducing tensions on the tissues and overall inflammatory responses [18].

This study confirms the evidence that delayed primary closure is a safer and more effective method of managing class III and IV abdominal wounds. However, this requires careful wound care in the open phase, and it is only so successful if strict practices on asepsis and timely closure are adhered to [19-20].

Therefore, delayed primary closure is much preferable to primary closure for contaminated and infected abdominal wounds since it does offer benefits such as lower SSI rates, faster wound healing, shorter hospital stays, and lower complications. Such findings make the advocacy of adopting delayed primary closure as a preferred technique in class III and IV wounds with the possibility of improving patients' outcomes and reducing healthcare costs. To establish the validity of such results, further large-scale studies are necessary, further testing the potential applicability across different surgical settings and patient populations.

Conclusively, the present work established that delayed primary closure is better than the traditional method of primary closure of class III and IV abdominal wounds with major reductions in surgical site infections, quicker healing of the wound, shorter stay in the hospitals, and fewer postoperative complications. Delayed primary closure minimizes bacterial contamination by allowing some preliminary wound drainage and granulation tissue formation prior to closure, thus providing an ideal healing environment. These findings emphasize the benefit of targeted approaches to surgery in at-risk wounds, and call for more widespread implementation of delayed primary closure to benefit patient outcomes and curb healthcare-associated infection.

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