Sonographic approach to dyspnea (mnemonic)

This mnemonic will help with the sonographic approach to the critically ill patient with dyspnea:

• CHEST

Mnemonic

• C: collapsed lung (pneumothorax) 
  • absence of anterior lung sliding, lung pulse, B-lines, or z-lines
    • these artifacts arise from the pleural interface; their presence would rule out pneumothorax
  • lung point highly specific ¹
• H: heart failure (acute pulmonary edema)
  • diffuse bilateral anterior B lines associated with lung sliding ¹
  • three or more B-lines per sonographic field garner the name "lung rockets"
    • the presence of lung rockets is highly suggestive of alveolar or interstitial edema
  • pleural line should appear thin and smooth
    • pleural thickening and/or irregularities may imply an inflammatory etiology to the edema
• E: effusion (pericardial effusion) 
  • pericardial effusion appears as an anechoic space between the visceral and parietal pericardia
    • with the development of tamponade physiology one may also see right atrial systolic collapse, right ventricular diastolic collapse, a dilated and invariable inferior vena cava, and variation in the mitral inflow velocity >25% with spontaneous respiration 
• S: sepsis (pneumonia)
  • air bronchograms/ B lines/subpleural consolidation 
  • fluid bronchograms/pleural effusion 
  • a collapsed inferior vena cava compatable with distributive shock and central venous hypovolemia may also be observed
• T: thromboembolism (pulmonary embolism/deep vein thrombosis) 
  • PE: subpleural consolidation (size 0.5-3 cm) and right heart strain 
  • DVT: non-compressible vein in femoral or popliteal zone ²