Objective: To determine if patients who receive emergency physician focused cardiac ultrasound (EP FOCUS) have reduced time to diagnosis for ascending aortic dissection (AAD).
Design: retrospective cohort analysis
Setting: three hospitals within a multihospital health care system: hospital 1 a large urban, nonprofit, level 1 trauma academic tertiary medical center; hospital 2 a small, suburban, nonprofit, community-based freestanding ED; and hospital 3 a large urban, nonprofit, academic community-based hospital.
Inclusion Criteria: diagnosis of AAD either in ED or as a discharge diagnosis after hospitalization
Exclusion Criteria: transfer from a referring facility with a known diagnosis of aortic dissection, history of acute trauma, non-treatment in ED, medical record review non-supportive of AAD, AAD defined as distal to the left subclavian artery, treatment at an alternative affiliated non-study site, arrival to ED in cardiac arrest
Methods: EMR was queried for all patients who had a diagnosis of aortic dissection in the ED or as a discharge diagnosis after hospitalization between March 1, 2013 and May 1, 2015. All hospital autopsy reports during this time were also manually reviewed for aortic dissection resulting in death. The primary outcome measure was time to diagnosis as defined by the difference between the time being roomed in the ED treatment area to diagnosis of AAD. Secondary outcome measures were time to disposition, misdiagnosis rate, and mortality differences between cohorts. All information was obtained from study patients EMR.
Results : A total of 32 patients were identified as having AAD meeting criteria for analysis. 16 patients were in the EP FOCUS group, and 16 patients were in the non-EP FOCUS group. The median time to diagnosis in the FOCUS group was 80 minutes (IQR 46 - 157). The median time to diagnosis in the non-FOCUS group was 226 minutes (IQR 109 - 1449). Difference in mean time to diagnosis was statistically significant with a p-value of 0.023. Those in the FOCUS group had a faster, though non-significant rooming time to disposition (median, 134 [IQR, 101 - 195] vs 205 [IQR, 114-342] minutes; p = 0.27) The misdiagnosis rate was 0% in the FOCUS group and 43.8% in the non-FOCUS group (p = 0.028). Mortality percentage adjusted for patients with DNR in the FOCUS vs non-FOCUS group was 15.4% vs 37.5% (p = 0.24).
Takeaway: This is the first study to show that patients receiving emergency physician focused cardiac ultrasound (EP FOCUS) were diagnosed as having ascending aortic dissections faster and misdiagnosed less compared to those who did not undergo EP FOCUS. As time to diagnosis and treatment of AAD is directly related to mortality, it is hypothesized that performance of EP FOCUS can improve mortality from AAD, but further study with larger sample sizes is required as this study found no significance and only a trend.
Importantly, ascending aortic dilation identified by FOCUS is approximately 70% sensitive for AAD, which outperforms the findings of aortic insufficiency on cardiac auscultation (44%), pulse deficit (19%), chest radiograph with wide mediastinum (62%), abnormal aortic contour (47%), and ECG findings (17-25%). EP FOCUS can be performed rapidly at the bedside for patients with concerning symptoms. In the FOCUS group studied here, 6/16 patients had a diagnosis made within 60min, demonstrating the speed in which FOCUS can be performed.
Reference:
Pare JR, Liu R, Moore CL, Sherban T, Kelleher MS Jr, Thomas S, Taylor RA. Emergency physician focused cardiac ultrasound improves diagnosis of ascending aortic dissection. Am J Emerg Med. 2016 Mar;34(3):486-92. doi: 10.1016/j.ajem.2015.12.005. Epub 2015 Dec 12. PMID: 26782795.
Author: Abigail Lauder, MS4