BLUE protocol ultrasonography in Emergency Department patients presenting with acute dyspnea

Dyspnea is a common Emergency Department (ED) symptom requiring prompt diagnosis and treatment. The bedside lung ultrasonography in emergency (BLUE) protocol is defined as a bedside diagnostic tool in intensive care units. The aim of this study was to investigate the test performance characteristics of the BLUE-protocol ultrasonography in ED patients presenting with acute dyspnea.

This study was performed as a prospective observational study at the ED of a tertiary care university hospital over a 3-month period. The BLUE-protocol was applied to all consecutive dyspneic patients admitted to the ED by 5 emergency physicians who were certified for advanced ultrasonography. In addition to the BLUE-protocol, the patients were also evaluated for pleural and pericardial effusion.

A total of 383 patients were included in this study (mean age, 65.5 ± 15.5 years, 183 (47.8%) female and 200 (52.2%) male). According to the BLUE-protocol algorithm, the sensitivities and specificities of the BLUE-protocol are, respectively, 87.6% and 96.2% for pulmonary edema, 85.7% and 99.0% for pneumonia, 98.2% and 67.3% for asthma/COPD, 46.2% and 100% for pulmonary embolism, and 71.4% and 100% for pneumothorax. Although not included in the BLUE-protocol algorithm, pleural or pericardial effusion was detected in 82 (21.4%) of the patients.

The BLUE-protocol can be used confidently in acute dyspneic ED patients. For better diagnostic utility of the BLUE-protocol in EDs, it is recommended that the BLUE-protocol be modified for the assessment of pleural and pericardial effusion. Further diagnostic evaluations are needed in asthma/COPD groups in terms of the BLUE-protocol.