A haemothorax is a collection of blood in the pleural space. It can be caused by penetrating or blunt thoracic trauma.
Patients with a massive haemothorax are generally unstable – this should be detected clinically (as part of the primary survey)
Smaller haemothoraces may have subtle clinical findings
CXR: A small haemothorax might not be evident on CXR (especially if supine) – look for subtle increase opacification over the affected hemi-thorax.
Around 350-400ml of blood needs to be present before blunting of the costophrenic angle becomes evident on an erect CXR.
USS has a higher sensitivity than CXR for detecting smaller haemothoraces (92% sensitivity in one study).1
CT is the definitive imaging study for detecting a haemothorax
As there is a risk that an undrained haemothorax can lead to retained clot and then empyema, haemothoraces that are estimate to be 300-500ml or greater should be considered for drainage.
Controversy exists over the best size drain to insert – moderate sized drains (28-32F) have been shown to be as effective as large drains (36-40F) in managing traumatic haemothorax.3 Some studies have even shown that smaller (14F) pigtail drains might be as efficacious as larger drains4 however more research is needed.5
At present, it is still recommended that a larger bore drain (ie: 28-32 F) be inserted for patient with traumatic haemothoraces. See tube thoracostomy insertion.
Disposition – interhospital transfer guidelineshaemothorax