A lung ultrasound can detect patients who are at increased risk for pulmonary embolism better than the commonly used Wells score (a pulmonary embolism probability scoring).
The technique can also help diagnose pneumonia or pleural effusion, the excess fluid that can build up between the lung and chest wall.
These are the findings of a study to be published in March in the journal Academic Emergency Medicine (AEM), a journal of the Society for Academic Emergency Medicine.
Pulmonary embolism is a life-threatening condition caused by a blocked artery in the lungs by a substance that has traveled from elsewhere in the body through the bloodstream (an embolism). Symptoms of pulmonary embolism may include shortness of breath, chest pain (particularly when breathing in), and coughing up blood. These symptoms can also indicate pneumonia.
Estimates from the European Society of Cardiology (ESC) indicate that at least 600,000 cases of pulmonary embolism are diagnosed each year in the United States. Mortality rates from pulmonary embolisms remained high because it was difficult to diagnosis. Pulmonary angiography has long been the gold standard to diagnosis pulmonary embolism (PE), but the technique is invasive, costly, and sometimes difficult to get a clear conclusion.
Recent evidence has demonstrated that ultrasound can be used for the diagnoses of various pulmonary, pleural, and mediastinal pathologies, including pneumonia. Until now, however, the diagnostic value of PE ultrasound remained uncertain.
In the new study, Dr. Peiman Nazerian and colleagues suggested that transthoracic lung ultrasound can show alternative diagnoses to pulmonary embolism, such as pneumonia or pleural effusion.
These findings corroborated previous results from a meta-analysis published in the journal PloS One, in which researchers in China assessed the overall accuracy of the transthoracic lung ultrasound in the diagnosis of a pulmonary embolism, and found the strategy accurate and helpful in diagnosing the condition.
Taken together, the results indicate that clinicians should consider using lung ultrasound when evaluating patients with a suspected pulmonary embolism, pneumonia, or pleural effusion.
“One of the largest criticisms of the widely used Wells score for estimating likelihood of potentially fatal blood clots in the lung (PE) is the vagary that surrounds the definition of its term, ‘alternative diagnosis more likely than PE,'” Jeffrey Kline, vice chair of research in the Department of Emergency Medicine and professor in the Department of Cellular and Integrative Physiology at Indiana University School of Medicine, said in a news release.
“Most clinicians who believe an alternative diagnosis is more likely than PE cannot name the diagnosis,” he said. “Nazerian et al, show that lung ultrasound can quickly and noninvasively allow physicians to literally see the identity of ‘something else wrong’ other than blood clots in the lung. This advantage can help them be more confident in deciding not to order expensive testing that causes large doses of radiation exposure to patients.”