From the Guidelines
The A-line and pleural line in the Meyers space are crucial for lung ultrasound assessment, with the pleural line appearing as a horizontal hyperechoic line that slides during respiration, and A-lines indicating normal aeration as horizontal reverberation artifacts. When examining the Meyers space, it is essential to position the ultrasound probe perpendicular to the ribs with the probe marker oriented cephalad (toward the patient's head) to visualize the pleural line and A-lines effectively [ 1 ]. The presence of A-lines suggests normal lung aeration, whereas the absence of A-lines or the presence of B-lines (vertical artifacts) may indicate interstitial syndrome or other lung pathologies [ 2 ].
Key Points for Assessment
- The pleural line is a horizontal hyperechoic line that slides during respiration, indicating the interface between the parietal and visceral pleura.
- A-lines are horizontal reverberation artifacts that indicate normal lung aeration.
- B-lines are vertical artifacts that suggest interstitial syndrome or other lung pathologies.
- The Meyers space allows for clear visualization of the pleural interface while minimizing rib shadowing artifacts.
Clinical Decision-Making
In critical care and emergency settings, accurate interpretation of lung ultrasound findings is crucial for clinical decision-making. The assessment of the A-line and pleural line in the Meyers space, as described by Lichtenstein, is a reliable tool for evaluating lung pathologies, including diffuse parenchymal lung disease, pleural effusion, and pneumothorax [ 3, 4 ]. By systematically scanning multiple Meyers spaces in each lung zone, clinicians can quickly and accurately diagnose lung pathologies, guiding subsequent management and treatment.
From the Research
Significance of A-line and Pleural Line
- The A-line is a horizontal artifact that can be seen in lung ultrasound, indicating the presence of air in the lungs 5.
- The pleural line is a critical landmark in lung ultrasound, representing the interface between the lung parenchyma and the pleural space 6, 7, 8, 5, 9.
- The presence and characteristics of the pleural line can help diagnose various lung conditions, such as pneumothorax, pleural effusion, and lung consolidation 6, 7, 8, 5, 9.
Lung Ultrasound Findings
- The combination of A-lines, B-lines, lung sliding, and pleural line characteristics can help diagnose specific lung conditions, such as pulmonary edema, pneumonia, and acute respiratory distress syndrome (ARDS) 6, 7, 8, 5, 9.
- The BLUE protocol, which assesses lung ultrasound findings, can help diagnose acute respiratory failure with high sensitivity and specificity 5.
- Lung ultrasound can also help differentiate between cardiogenic and noncardiogenic causes of pulmonary edema, such as ARDS and cardiogenic pulmonary edema 9.
Clinical Applications
- Lung ultrasound can be used as a bedside tool for rapid diagnosis and monitoring of lung conditions in critically ill patients 6, 7, 8, 5, 9.
- The use of lung ultrasound can help reduce the need for chest radiography and other imaging modalities, improving patient outcomes and reducing healthcare costs 6, 7, 8, 5, 9.