- To show the normal ultrasound appearance of the lung and the basic ultrasound lung signs. - To illustrate the main causes of dyspnea and their lung ultrasound patterns. - To assess the diagnostic accuracy of lung ultrasound versus chest radiography or CT.
Dyspnea is one of the most challenging complaint in the emergency department.
The cause of dyspnea (cardiogenic or non-cardiogenic) must be rapidly established as it is a potentially life-threatening illness.
Chest radiograhy has limitations in diagnosing pleuro-pulmonary diseases,
while thoracic CT has several drawbacks such as irradiation,
costs and the need for transportation.
Lung ultrasound helps to rapidly identify the cause of dyspnea (pulmonary edema,
Findings and procedure details
Normal lung appearance When performing a thoracic ultrasound,
structures explored are skin,
endothoracic membrane and the pleura (parietal and visceral pleura).
Several sign have been described: 1. Pleural line - the interface between the soft tissue structures and the air in the lung; it is an echogenic line measuring < 3 mm. 2. Sliding sign or ‘sliding lung’- the pleura that glides during respiratory movements.
The presence of the sliding sing rules...
Lung ultrasound is a fast,
simple and accurate diagnostic tool superior to chest radiography and sometimes to thoracic CT in dyspneic patients.
Its accurracy can be even higher when combined with physical examination,
laboratory findings and diagnostic protocols such as the BLUE- protocol (bedside lung ultrasound in emergency).
1. Lichtenstein DA,
A-lines and B-lines: lung ultrasound as a bedside tool for predicting pulmonary artery occlusion pressure in the critically ill, Chest. 2009 Oct;136(4):1014-1020.
doi: 10.1378/chest.09-0001. 2. Lichtenstein DA,
BLUE-Protocol and FALLS-Protocol Two Applications of Lung Ultrasound in the Critically Ill,
June 2015, http://journal.publications.chestnet.org/ 3. Lichtenstein D,
Comparative diagnostic performances of...