Written by Chris Thom
Spoon Feed
This narrative review of lung ultrasound provides an evidence-based overview of acquisition techniques, clinical protocols, common pathologies, and potential pitfalls.
A game of artifacts
Lung ultrasound is often discussed as being a bit late to the ultrasound party. Previously, it was thought that lung ultrasound would be of low utility given the innate problems with combining ultrasound imaging and air. However, in the last few decades, significant research has cemented lung ultrasound’s role in multiple clinical scenarios. Pneumothorax, pulmonary edema, atelectasis, pneumonia, and pleural effusions are key pathologies wherein lung ultrasound has proven benefit. The lung ultrasound evaluation for pneumothorax outperforms supine chest radiography by a significant margin. Look for an absence of sliding lung due to the pathologic separation of the parietal and visceral pleura. Pulmonary edema can be identified easily via the appearance of “B-lines” on ultrasound, which appear as vertical echogenic lines transmitting deep to the pleural line. Be aware that other lung pathologies can also be associated with a B-line pattern, including ARDS, pulmonary contusion, and atypical or viral pneumonia. Various protocols have been developed to assist in patients with shortness of breath, including the BLUE (bedside lung ultrasound in emergency) protocol.
How will this change my practice?
Lung ultrasound is here to stay. It can be rapid and highly useful in a variety of scenarios. Once you have experienced the impact of lung ultrasound on the immediate management of the undifferentiated dyspneic patient in severe distress, it is hard to go back to a reliance on auscultation and the often-tardy chest radiograph. The rapid differentiation of edema versus air trapping in a patient with histories of both CHF and COPD is very empowering and consequential. And while some applications like pneumonia can require longer acquisition time, many core lung ultrasound techniques are just as rapid as auscultation. The evidence is clear: You owe it to your patients to pick up the probe for lung ultrasound, particular in the diagnosis of pulmonary edema and pneumothorax.
Source
Nuts and bolts of lung ultrasound: utility, scanning techniques, protocols, and findings in common pathologies. Crit Care. 2024 Oct 7;28(1):328. doi: 10.1186/s13054-024-05102-y. PMID: 39375782
