Delaying surgery to perform CT scans for suspected appendicitis decreases the rate of negative appendectomies without increasing the rate of perforation nor postoperative complications.

Purpose: Negative appendectomies are costly and are embedded with unnecessary risks for the patients. A careful indication for surgery seems mandatory even more so, since conservative therapy emerges as a potential alternative to surgery. The aims of this population-based study were to analyze whether radiological examinations for suspected appendicitis decreased the rate of negative appendectomies without increasing the rate of perforation or worsening postoperative outcomes.

Method: This study is a retrospective analysis of a prospective population-based database. The data collection included preoperative investigations and intraoperative and postoperative outcomes.

Results: Based on 2559 patients, the rate of negative appendectomies decreased significantly with the use of CT scan as compared to clinical evaluation only (9.3 vs 5 %, p = 0.019), whereas ultrasonography alone was not able to decrease this rate (9.3 vs 6.2 %, p = 0.074). Delaying surgery for radiological investigation did not increase the rate of perforation (18.1 vs 19.2 %; adjusted odds ratio (OR) 1.01; 0.8-1.3; p = 0.899). Postoperative complications (surgical reintervention, postoperative wound infection, postoperative hematoma, postoperative intra-abdominal abscess, postoperative ileus) were all comparable.

Conclusion: In this population-based study, CT scan was the only radiological modality that significantly reduced the rate of negative appendectomy. The delay induced by such additional imaging did not increase perforation nor complication rates. Abdominal CT scans for suspected appendicitis should therefore be more frequently used if clinical findings are unconclusive.