Impact of oral contrast use in CT imaging for acute appendicitis on time to surgery: a single-center before-after cohort study

Background: Timely diagnosis and treatment are critical for reducing complications and mortality in acute appendicitis. The use of oral contrast in computed tomography (CT) imaging remains a standard diagnostic practice in some institutions when acute appendicitis is suspected. Recent evidence, however, suggests that in cases with high clinical suspicion, oral contrast does not improve diagnostic accuracy and may lead to unnecessary delays in care. Methods: This single-center retrospective before-after cohort study included 118 adult patients who underwent appendectomy at a hospital in northern Israel in 2022. In the pre-implementation period, patients underwent CT with intravenous (IV) and oral contrast, whereas in the post-implementation period they underwent CT with IV contrast only, following new hospital guidelines. Data were extracted from electronic medical records, and the primary outcome was the time interval (in minutes) from emergency department (ED) presentation to entry into the operating room (OR). Statistical analyses were performed using non-parametric tests. Results: Patients who received IV contrast only had a significantly shorter time from ED admission to OR entry compared to those who received both oral and IV contrast (median: 489 vs 662 minutes; P < 0.001). The most notable delay occurred between initial physician evaluation and CT result availability (183 vs 267 minutes; P < 0.001). Other clinical and demographic characteristics were similar between groups. Conclusions: Removing oral contrast from CT protocols for suspected appendicitis shortened time to surgery, with a median reduction of 173 minutes (~2.9 hours). These findings support streamlined imaging workflows and underscore the value of protocol optimization in emergency care.