Venous thromboembolism (VTE), which includes DVT and pulmonary embolism (PE), is the third leading cause of cardiovascular death among Americans and is especially fatal if these events go undiagnosed and are not treated promptly. PE is most frequently diagnosed in the ED and is associated with 14- and 30-day mortality rates of about 10% and 20%, respectively. Research has shown that a prompt diagnosis of acute PE—within 48 hours of ED arrival—is associated with improved outcomes.
Factors Associated with Delays in PE Diagnosis
My colleagues and I previously reported that administration of anticoagulants within 24 hours of ED arrival is associated with reduced mortality. Current guidelines from the American College of Chest Physicians recommend that anticoagulation be initiated even before a confirmed diagnosis, when the probability of PE is believed to be high. However, studies have indicated that there is potential for significant delays from the time of symptom onset to PE diagnosis in the ED.
A prompt diagnosis of acute PE—within 48 hours of ED arrival—is associated with improved outcomes.
In an effort to better understand the factors associated with timing of a PE diagnosis in the ED, my colleagues and I conducted a review that was published in the January 2012 Journal of Emergency Medicine. Following univariate and multivariate analyses, we found that the following factors appeared to be associated with delays in PE diagnoses of more than 12 hours:
Age older than 65.
Concurrent cardiovascular disease (CVD).
Morbid obesity (BMI >40 kg/m2).
A history of recent immobility (eg, recent surgery) and presentation to the ED with tachycardia were factors associated with a relatively early diagnosis of PE.
Patients older than 65 who present to the ED often have complicated medical histories, meaning they’ll require clinicians to take more time to address multiple factors. Our observed association of morbid obesity with delayed PE diagnosis may be due to the fact that it’s difficult to be confident on findings from cardiac auscultation due to obscure breathing patterns among this population. Also, many CAT scanners—which we used to diagnose all patients in our study—don’t accommodate people who weigh more than 300 lbs.
Important Considerations for PE Diagnosis
It’s important to note that up to 20% of PE diagnoses in the ED or shortly thereafter may be incidental because patients are presenting with no symptoms that can be attributable to PE. In our study, we confined our data to include those who presented with cardiopulmonary symptoms. For patients with concurrent CVD, it’s natural for clinicians to prioritize CVDs ahead of acute PE.
Applying Findings to Practice
Our study suggests that clinicians should be prompted to obtain a D-dimer test, calculate a Wells criteria score, or administer other appropriate testing for PE when patients present to the ED who are older than 65, have underlying CVD, or are morbidly obese, and have new-onset dyspnea, chest pain, or hemoptysis. Items on the differential diagnosis of patients with CVD, morbid obesity, or age over 65 must be considered, but clinicians shouldn’t have premature diagnostic closure and cast a wide net that includes PE on the list. It’s imperative that efforts are made to prevent VTE in the hospital. Recognizing the risk factors associated with PE in the ED and understanding why diagnoses are sometimes delayed is crucial in catching PE early and treating it appropriately. The hope is that this will translate into reductions in associated morbidity and mortality.
Readings & Resources (click to view)
Smith S, Geske J, Morgenthaler T. Risk factors associated with delayed diagnosis of acute pulmonary embolism. J Emerg Med. 2012;4:1-6. Abstract available at: www.jem-journal.com/article/S0736-4679(11)00623-8/abstract.
Bulbul Y, Ozsu S, Kosucu P, et al. Time delay between onset of symptoms and diagnosis in pulmonary thromboembolism. Respiration. 2009;78:36-41.
Ozsu S, Oztuna F, Bulbul Y, et al. The role of risk factors in delayed diagnosis of pulmonary embolism. Am J Emerg Med. 2011;29:26-32.
Smith S, Geske J, Maguire J, et al. Early anticoagulation is associated with reduced mortality for acute pulmonary embolism. Chest. 2010;137:1382-1390.
Holst A, Jensen G, Prescott E. Risk factors for venous thromboembolism: results from the Copenhagen City Heart Study. Circulation. 2010;121:1896-1903.
Al Otair H, Chaudhry M, Shaikh S, Bahammam A. Outcome of patients with pulmonary embolism admitted to the intensive care unit. Ann Thorac Med. 2009;4:13-16.