Observation Safely Reduces the Use of the Computerized Tomography in Medium-to-Low-Risk Patients with Suspected Acute Appendicitis: Results of a Randomized Controlled Trial.

Objectives -The objective was to compare the effectiveness of observation in standard-of-care computed tomography (CT) in adult patients with suspected acute appendicitis (AA). Methods -Patients with clinically suspected AA and inconclusive diagnosis after primary clinical examination, laboratory examination, and transabdominal ultrasound (TUS) were eligible for the study, and they were randomized (1:1) to parallel groups: observation-group patients were observed for 8-12 h and then, repeated clinical and laboratory examinations and TUS were performed; CT group (control group) patients underwent abdominopelvic CT scan. The study utilized Statistical Analysis System 9.2 for data analysis, including tests, logistic regression, ROC analysis, and significance evaluation. Patients were enrolled in the study at Vilnius University Hospital Santaros Klinikos in Lithuania between December 2018 and June 2021. Results -A total of 160 patients (59 men, 101 women), with a mean age of 33.7 ± 14.71, were included, with 80 patients in each group. Observation resulted in a reduced likelihood of a CT scan compared with the CT group (36.3% vs. 100% p < 0.05). One diagnostic laparoscopy was performed in the observation group; there were no cases of negative appendectomy (NA) in the CT group. Both conditional CT and observation pathways resulted in high sensitivity and specificity (97.7% and 94.6% vs. 96.7% and 95.8%). Conclusions -Observation including the repeated evaluation of laboratory results and TUS significantly reduces the number of CT scans without increasing NA numbers or the number of complicated cases.