Chest x-ray review: ABCDE

Last revised by Hector Lopez-Cardona on 14 Nov 2023

Chest x-ray review is a key competency for medical students, junior doctors and other allied health professionals. Using A, B, C, D, E is a helpful and systematic method for chest x-ray review:

  • A: airways

  • B: breathing (the lungs and pleural spaces)

  • C: circulation (cardiomediastinal contour)

  • D: disability (bones - especially fractures)

  • E: everything else, e.g. pneumoperitoneum

Summary

Airways

Start at the top in the midline and review the airways.

  • trace down the trachea to the carina

    • is it straight and midline?

    • is there any narrowing?

  • trace down both main bronchi

    • is the carina wide (more than 100 degrees)?

    • is there bronchial narrowing or cut-off?

    • is there any inhaled foreign body?

Read more: chest x-ray assessment of the airways

Breathing

Look for lung and pleural pathology.

  • both lungs should be well expanded and similar in volume

    • can you count 10 posterior ribs bilaterally?

    • is one lung larger than the other?

  • compare the apical, upper, middle and lower zones in turn

    • are they symmetrical?

    • are there areas of increased density?

  • trace the lung vessels

    • do they branch out progressively and uniformly?

    • can you see the retrocardiac and retrodiaphragmatic lung vessels?

    • are there extra lines in the periphery that aren't vessels?

  • trace the lateral margins of the lung to the costophrenic angles

    • are the costophrenic angles crisp?

  • trace the hemidiaphragms in to the vertebra

    • can you see the whole of the hemidiaphragm?

  • trace the cardiac borders

    • can you clearly see the left and right heart border?

    • can you see the descending aorta?

Read more: chest x-ray assessment of lungs and pleural spaces

Circulation

Look at the heart and vessels (systemic and pulmonary).

  • check the cardiac position

    • is 1/3 to the right and 2/3 to the left?

  • assess cardiac size

    • is the cardiothoracic ratio < 50%?

  • check the position and size of the aortic arch and pulmonary trunk

  • check the width of the upper mediastinum

  • look at the hilar vessels

    • can you see them clearly on both sides?

    • are they at a similar height?

    • can you see a preserved hilar point bilaterally? 

Read more: chest x-ray assessment of the cardiomediastinum

Disability

Check for any bony pathology (fracture or metastasis).

  • trace along each posterior (horizontal) rib on one side of the chest

    • is there a fracture or abnormal area?

  • repeat with the other side of the chest

  • now trace lateral and anterior ribs on the first side

  • repeat on the other side

  • now, check the clavicles and shoulders

    • can you trace around the cortex of the bones?

  • finally the check the vertebral bodies

    • are they all rectangular and of a similar height?

    • can you see 2 pedicles per vertebral body?

    • are there disc spaces?

Read more: chest x-ray assessment of the bony thorax

Everything else

Review the upper abdomen, soft tissues and take a look at some final check areas.

  • is there free gas under the diaphragms?

  • is there subcutaneous emphysema?

  • is the gastric bubble in the correct place?

  • is there a hiatus hernia?

  • is there an absent breast shadow?

  • are there any surgical clips?

  • check again...

    • are the lung apices clear?

    • is there any retrocardiac or retrodiaphragmatic pathology?

Read more: chest x-ray assessment of everything else

ADVERTISEMENT: Supporters see fewer/no ads

Cases and figures

  • Figure 1: airway
    Drag here to reorder.
  • Figure 2: breathing
    Drag here to reorder.
  • Figure 3: circulation
    Drag here to reorder.