A massive haemothorax is an expanding haemothorax. The signs will be less reliable in diagnosing a moderate haemothorax.

Listen at the lung bases (image, below left). There should be clear signs of shock prompting you to consider the diagnosis. Use CXR and eFAST to guide you.

Fig 7. Lung bases Fig 8. Haemothorax Fig 9. Free fluid
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