Accuracy of sonography performed by emergency medicine residents for the diagnosis of acute appendicitis

Abstract

Study objectives: We evaluate the accuracy of sonography performed by emergency medicine residents for the diagnosis of acute appendicitis with equivocal physical findings. Methods: In this prospective study, 40 consecutive patients with equivocal physical findings of acute appendicitis were examined with graded compression sonography by emergency medicine residents after a 1-hour lecture and 20 observations. The primary sonographic criterion for diagnosing acute appendicitis was an incompressible appendix with a outer diameter of 6 mm or larger with periappendicular inflamed fat with or without an appendicolith. The sonographic findings were correlated with surgical and pathologic findings. Results: Among 40 patients studied, 29 patients were confirmed to have acute appendicitis, and 11 patients were confirmed to have other pathology during operation. Among 29 patients who had an acute appendicitis, 24 patients were diagnosed by sonography, and 5 patients did not have sonographic diagnosis of acute appendicitis. The 11 patients who did not have acute appendicitis during operation also did not have sonographic criteria for acute appendicitis. Those 5 patients who did not have sonographic criteria for acute appendicitis all had positive computed tomographic scan results for acute appendicitis. The sensitivity of emergency medicine residents diagnosing acute appendicitis by sonography was 83%, and specificity was 100%. The positive predictive value was 100% and negative predictive value was 69%. Conclusion: The sonography performed by emergency medicine residents is useful for diagnosing acute appendicitis among patients with equivocal physical findings. Study objectives: We evaluate the accuracy of sonography performed by emergency medicine residents for the diagnosis of acute appendicitis with equivocal physical findings. Methods: In this prospective study, 40 consecutive patients with equivocal physical findings of acute appendicitis were examined with graded compression sonography by emergency medicine residents after a 1-hour lecture and 20 observations. The primary sonographic criterion for diagnosing acute appendicitis was an incompressible appendix with a outer diameter of 6 mm or larger with periappendicular inflamed fat with or without an appendicolith. The sonographic findings were correlated with surgical and pathologic findings. Results: Among 40 patients studied, 29 patients were confirmed to have acute appendicitis, and 11 patients were confirmed to have other pathology during operation. Among 29 patients who had an acute appendicitis, 24 patients were diagnosed by sonography, and 5 patients did not have sonographic diagnosis of acute appendicitis. The 11 patients who did not have acute appendicitis during operation also did not have sonographic criteria for acute appendicitis. Those 5 patients who did not have sonographic criteria for acute appendicitis all had positive computed tomographic scan results for acute appendicitis. The sensitivity of emergency medicine residents diagnosing acute appendicitis by sonography was 83%, and specificity was 100%. The positive predictive value was 100% and negative predictive value was 69%. Conclusion: The sonography performed by emergency medicine residents is useful for diagnosing acute appendicitis among patients with equivocal physical findings.