Delayed Versus Early Laparoscopic Appendectomy for Adult Patients With Acute Appendicitis: A Randomized Controlled Trial.

OBJECTIVE: To assess whether delaying appendectomy until the following morning is non-inferior to immediate surgery in those with acute appendicitis presenting at night. BACKGROUND: Despite a lack of supporting evidence, those with acute appendicitis who present at night frequently have surgery delayed until the after morning. METHODS: The delay trial is a noninferiority randomized controlled trial conducted between 2018 and 22 at 2 tertiary care hospitals in Canada. Adults with imaging confirmed acute appendicitis who presented at night (8:00 pm -4:00 am ). Delaying surgery until after 6:00 am was compared with immediate surgery. The primary outcome was 30-day postoperative complications. An a prior noninferiority margin of 15% was deemed clinically relevant. RESULTS: One hundred twenty-seven of the planned 140 patients were enrolled in the Delayed Versus Early Laparoscopic Appendectomy (DELAY) trial (59 in the delayed group and 68 in the immediate group). The two groups were similar at baseline. The mean time between the decision to operate and surgery was longer in the delayed group (11.0 vs 4.4 hours, P < 0.0001). The primary outcome occurred in 6/59 (10.2%) of those in the delayed group versus 15/67 (22.4%) of those in the immediate group ( P = 0.07). The difference between groups met the a priori noninferiority criteria of +15% (risk difference -12.2%, 95% CI: -24.4% to +0.4%, test of noninferiority P < 0.0001). CONCLUSIONS: The DELAY study is the first trial to assess delaying appendectomy in those with acute appendicitis. We demonstrate the noninferiority of delaying surgery until the after morning.