Perforated Appendicitis and Postoperative Antibiotics Pilot Trial (PAPA Pilot)

Acute appendicitis, a sudden and severe inflammation of the appendix, is the most common emergency general surgery condition worldwide. In some cases, the appendix perforates, leading to contamination or infection within the abdominal cavity. Complicated appendicitis is associated with higher morbidity and mortality, including a higher risk of surgical site infections (SSIs). Approximately 20% of patients with complicated appendicitis develop an SSI, compared to about 5% of patients with uncomplicated appendicitis.

The use of antibiotics before surgery is well established and standard practice to reduce SSI risk. However, there is limited evidence to guide the use of antibiotics after surgery in patients with complicated appendicitis. Antibiotics carry potential risks, including allergic reactions, gastrointestinal side effects, and secondary infections, and their overuse contributes to antimicrobial resistance, which is a growing global health concern. As a result, there is a considerable variation in clinical practice, with some surgeons routinely prescribing post-operative antibiotics and others choosing not to.

Large, high-quality randomized controlled trials (RCTs), the gold-standard in clinical research, are needed to understand if post-operative antibiotics are necessary in this population. The current study will evaluate the impact of post-operative antibiotics on SSIs in patients with perforated appendicitis. This pilot specifically aims to determine the feasibility of a larger, multi-centre RCT, and will assess our ability to enroll and randomize patients, and to collect complete health data using an existing framework. Patients will be randomly assigned to receive post-operative antibiotics or no post-operative antibiotics after surgery for perforated appendicitis, and will be followed until 30 days after surgery to assess incidence of SSIs, with additional outcomes collected up to 90 days post-surgery.