Impact of 24-hour specialist coverage and an on-site CT scanner on the timely diagnosis of acute aortic dissection

INTRODUCTION: Acute aortic dissection (AAD) is a rare and potentially fatal condition that has been known to be missed in diagnoses. Our primary objective was to determine if the availability of 24-hour emergency department (ED) specialist coverage and an on-site computed tomography (CT) scanner reduced the rate of missed diagnoses of AAD. METHODS: We selected records of patients diagnosed with dissection of the aorta from a hospital's discharge database and death register in the period of January 1998 to December 2014. AAD was defined as missed if imaging to diagnose AAD or a cardiology/cardiothoracic surgical consultation was not obtained in the ED. We compared the rates of missed diagnosis before and after the availability of 24-hour ED specialist coverage and an on-site CT scanner in the ED. RESULTS: Among 145 patients, 42 (29.0%) had a missed diagnosis. The proportion of missed AAD was lower in the post-implementation period compared to the pre-implementation period (20.0% vs. 37.3%, odds ratio [OR] 0.42, 95% confidence interval [CI] 0.20‒0.89; p = 0.023). After adjusting for confounders, the difference remained significant (OR 0.31, 95% CI 0.14‒0.70; p = 0.005). In the post-implementation period, concurrent signs of congestive cardiac failure (OR 33.51, 95% CI 1.42‒789.20; p = 0.024) and absence of a widened mediastinum on chest radiography (OR 11.52, 95% CI 1.37‒96.80; p = 0.029) were independent predictors of missed diagnoses. CONCLUSION: The availability of 24-hour ED specialist coverage and an on-site CT scanner improved the diagnosis of AAD in our study.