Abdominopelvic CT increases diagnostic certainty and guides management decisions: a prospective investigation of 584 patients in a large academic medical center

Abstract

Objective: The objective of our study was to prospectively determine how CT affects physicians' diagnostic certainty and management decisions in the setting of patients with nontraumatic abdominal complaints presenting to the emergency department.

Subjects and methods: We included 584 patients presenting with nontraumatic abdominal complaints to the emergency department from November 2006 through February 2008. Emergency department clinicians were prospectively surveyed both before abdominal CT (pre-CT) and after abdominal CT (post-CT) to determine the leading diagnosis, the diagnostic certainty, and the management decisions. Changes were assessed by Fisher's exact test and the log likelihood ratio.

Results: The most common diagnoses were renal colic (119/584, 20.4%) and intestinal obstruction (80/584, 13.7%). CT altered the leading diagnosis in 49% of the patients (284/584, p < 0.00001) and increased mean physician diagnostic certainty from 70.5% (pre-CT) to 92.2% (post-CT) (p < 0.001; log likelihood ratio, 2.48). The management plan was changed by CT in 42% (244/583) (p < 0.0001). Physicians planned to admit 75.3% of the patients (440/584) to the hospital before CT; that plan was changed to hospital discharge with follow-up in 24.1% of patients (106/440) after CT. Surgery was planned for 79 patients before CT, whereas hospital discharge was planned for 25.3% of these patients (20/79) after CT.

Conclusion: In the management of patients presenting to the emergency department with nontraumatic abdominal complaints, CT changes the leading diagnosis, increases diagnostic certainty, and changes potential patient management decisions.