Does selective use of computed tomography scan reduce the rate of "white" (negative) appendectomy?

Appendectomies are the most common operations performed on an emergency basis. The accepted rate of "white" appendectomies is around 20%. In recent years, computed tomography (CT) scanning has been recognized as a valuable tool with high sensitivity and specificity in the diagnosis of acute appendicitis. The use of CT scans in the management of patients with suspected acute appendicitis is increasing worldwide.

To assess whether introducing more liberal use of CT in the management of patients presenting to the emergency room with right lower quadrant pain or suspected acute appendicitis would reduce the rate of "white" appendectomies.

We conducted a retrospective study of the pathology reports and CT scans of all patients who underwent appendectomy during a 3 year period. We examined the correlation between the rate of CT scans performed and the rate of "white" appendectomies.

Overall, we performed 797 appendectomies during the study period. In 2004, we performed 272 appendectomies and CT in 34 patients (12.5%). In 2005, we performed 275 appendectomies and CT in 83 patients (30.2%). In 2006, we performed 250 appendectomies and CT in 88 patients (35.2%). The percentage of "white" appendectomies decreased from 29% in 2004 to 21.1% in 2005 and to 18.8% in 2006.

It appears that a more selective use of CT scans in the management of suspected appendicitis could reduce the rate of "white" appendectomies.