POCUS

Question 1

Lung Exam

Answer 1

Curved probe (Abdo) -- low frequency
Linear probe -- high frequency
**Curved probe** for everything except when looking for lung sliding then Linear probe.

• *Probe should be saggital:**
  1. Check upper chest, midline, between 2nd and 3rd intercostal space. Pneumothorax will rise to the top. Angle back and forth until view is perpendical to chest.

2. Check lower chest, above diaphragm, near axilla. Stay perpindicular to thorax.

Artifacts
1. Plueral sliding – hyperechoic pleural line sliding back and forth, like the sinus rhythm of ultrasound. Ants on a string.
Absence of lung sliding does NOT rule in a pneumothorax.For example, previous surgery, scarring. Presence of pleural sliding rules OUT a pneumothorax.

2. A Lines – reverberations from air under the pleural line. Equally spaced representations of the pleural line. A Lines tell you there is AIR or MOSTLY AIR deep to the pleural line.
Pneumothorax is characteristic of A Lines (or AIR) without sliding.
Note: The lines exist because the machine interprets time of returning signal as depth.

If dyspena and patient has Pleural Sliding and A Lines in multiple lung fields then DDx:

1. COPD
2. Asthma
3. PE
4. Non Cardiogenic cause of dyspnea such as anemia, anxiety etc.

3. B Lines – hyperechoic, starts at pleural line, moves with respiration, extends off the screen, *erases A Lines

DDx:

1. Alveolar/Interstitial fluid
2. Pulmonary edema
3. Lung Contusion
4. Pneumoniae/ARDS
5. * Fibrosis