Povidone-iodine Irrigation for Prevention of Intra-abdominal Abscess in Pediatric Perforated Appendicitis: a Multi-center Stepped Wedge Cluster Randomized Study

The intervention will be irrigation with PVI, diluted to a concentration of 1% (containing 0.1% active iodine). After removal of the appendix from the patient's abdomen and attainment of hemostasis,10 mL/kg of 1% PVI solution will be used to irrigate the pelvis and right upper and lower quadrants. The solution will be left to dwell for 1 minute and then suctioned.

The control will be usual care, which is expected to vary between institutions. The only stipulation for usual care will be that surgeons do not change their usual practice during the baseline period. Some surgeons utilize intra-abdominal irrigation while others use only local irrigation. Intraabdominal irrigation is defined as intraoperative instillation of a large volume (\> 200 mL) of irrigation solution into all 4 quadrants of the abdomen. Local irrigation is defined as instillation of a small volume of liquid, typically \<50 mL, in the operative field. Intra-abdominal irrigation is utilized with the intention of preventing IAAs while local irrigation is often used to confirm hemostasis or assist with suctioning thick purulent fluid.