College of Georgia
CT scan showing PE Image from Medical
There is no need for a structured algorithm to rule out pulmonary embolism (PE) in patients who visit the emergency department (ED) for syncope, according to researchers.
The team analyzed data on nearly 1.7 million patients who presented to the ED for syncope in 4 different countries.
PE occurred in less than 1% of these patients and in less than 3% of patients who were hospitalized.
The researchers therefore concluded that PE should be considered in such patients, but a systematic protocol for ruling out PE is not necessary.
“Our results are saying that there is no need, so far, for using a structured clinical algorithm to assess pulmonary emboli in all the patients presenting [to the ED with syncope],” said Nicola Montano, MD, PhD, of the University of Milan in Italy.
Dr Montano and his colleagues described these results in JAMA Internal Medicine.
The team noted that, in the PESIT trial, researchers used a standardized algorithm to evaluate PE prevalence in patients hospitalized after a first syncope episode.
The algorithm was based on pretest clinical probability and results of the D-dimer assay. Any patient with positive D-dimer results or high pretest PE probability underwent computed tomography or ventilation perfusion lung scanning.
In this study, the prevalence of PE was 17.3%.
A subsequent study showed a much lower prevalence of PE and deep vein thrombosis in patients hospitalized for syncope. The prevalence of venous thromboembolism (VTE) in this study was 1.4%.
The differences between these studies and the fact that both studies included only hospitalized patients prompted Dr Montano and his colleagues to conduct the current study.
The team set out to determine PE/VTE prevalence in unselected patients with syncope presenting to the ED.
Results
The researchers analyzed administrative data from 5 databases in 4 countries—Canada, Denmark, Italy, and the US—collected from January 1, 2000, through September 30, 2016.
The data included 1,671,944 adults who presented to the ED for syncope. The prevalence of PE at ED or hospital discharge ranged from 0.06% to 0.55%. Among the hospitalized patients only, the prevalence of PE ranged from 0.15% to 2.10%.
At 90 days of follow-up, the prevalence of PE ranged from 0.14% to 0.83% for all patients and from 0.35% to 2.63% for hospitalized patients.
The prevalence of VTE at 90 days ranged from 0.30% to 1.37% for all patients and from 0.75% to 3.86% for hospitalized patients.
The researchers said the main limitation of this study is the use of administrative data because some patients with syncope, PE, or VTE may have been missed.
