The goal of this clinical trial is to compare primary wound closure (PC) versus delayed primary closure (DPC) after standardized wound decontamination using the High-Efficiency Incision and Drainage with Irrigation (HIEDI) technique in patients undergoing open appendectomy for complicated appendicitis in Sana'a, Yemen.

The main questions it aims to answer are:

• Does primary closure with HIEDI result in a non-inferior or lower incidence of Surgical Site Infection (SSI) at 30 days compared with delayed primary closure with HIEDI?
• Does primary closure with HIEDI reduce length of hospital stay and improve the trajectory of objective wound healing compared with delayed primary closure with HIEDI?
• What is the impact of each closure method on patient satisfaction and health-related quality of life?

Researchers will compare the two groups to determine the optimal, evidence-based standard of care for wound management in complicated appendicitis within a resource-limited setting.

Participants will:

• Undergo open appendectomy for intraoperatively confirmed complicated appendicitis (perforation or gangrene).
• Receive standardized HIEDI wound decontamination (meticulous debridement and pulsatile irrigation with minimum 500 mL povidone-iodine 1:10 solution).
• Be randomly allocated to either primary closure (all layers closed at surgery) or delayed primary closure (skin/subcutaneous tissue left open and closed 3-5 days later).
• Attend follow-up visits at days 7, 14, and 30 for wound assessment, infection surveillance, and outcome evaluation.

Complicated appendicitis (perforation or gangrene) is a significant cause of postoperative morbidity worldwide. Surgical Site Infection (SSI) is the most common complication, with reported rates exceeding 30% in low- and middle-income countries (LMICs). In Sana'a, Yemen, local data from Al-Thawra Modern General Hospital documented a 27.5% SSI rate specifically in this patient population. The optimal wound closure strategy-primary closure (PC) versus delayed primary closure (DPC)-remains debated, with previous studies yielding conflicting results largely due to lack of standardized intraoperative wound decontamination.

The High-Efficiency Incision and Drainage with Irrigation (HIEDI) technique is a standardized, aggressive decontamination protocol combining meticulous debridement of wound edges with pulsatile high-pressure irrigation using a minimum of 500 mL of povidone-iodine solution (1:10 dilution). By applying HIEDI uniformly to both study arms, this trial isolates the effect of closure timing on SSI risk.

This is a prospective, multicenter, parallel-group, 1:1 randomized controlled superiority trial with blinded outcome assessment, conducted at three tertiary care hospitals in Sana'a, Yemen. The findings will provide high-level, locally generated evidence to establish a safe, resource-conscious standard of care for Yemen and similar settings.

Inclusion Criteria:

• Age 12 years and older
• Intraoperative diagnosis of complicated appendicitis (perforation or gangrene)
• Undergoing open appendectomy via McBurney or Rocky-Davis incision
• Ability to provide written informed consent (patient or legal guardian for minors)
• Availability for 30-day follow-up

Exclusion Criteria:

• Generalized peritonitis requiring midline laparotomy
• Immunocompromised status (e.g., chronic corticosteroid or immunosuppressive therapy, diagnosed HIV infection)
• Poorly controlled diabetes mellitus (Hemoglobin A1c [HbA1c] greater than 8%)
• Pregnancy
• Concurrent malignancy
• American Society of Anesthesiologists (ASA) physical status classification IV or V
• Laparoscopic appendectomy

The study team does not plan to share individual participant data with other researchers. This is a single-center thesis study with limited data management infrastructure, and the dataset contains identifiable clinical information that cannot be sufficiently de-identified for broad sharing under local ethical guidelines.

Due to the visible nature of the surgical interventions, blinding of surgeons and patients is not feasible. Outcome assessors evaluating Surgical Site Infection (SSI), data analysts, and laboratory personnel processing wound cultures are blinded to treatment allocation. Group assignments are coded as Group A and Group B until primary analysis is complete.