Hemothorax: Clinical sciences

A hemothorax is the collection of blood within the chest cavity, or the pleural space to be more specific. This collection can be a result of direct trauma to the chest, or can occur spontaneously when patients have pre-existing clotting disorders. It’s important to address the hemothorax in a timely manner to acutely avoid a potentially life-threatening hemorrhage, as well as to avoid chronically the formation of a fibrothorax, which is an organized clot within the chest cavity surrounding and restricting the patient’s lung from expanding.

When approaching a patient who presents with signs and symptoms suggestive of a hemothorax, your first step is to do an ABCDE assessment in order to determine if the patient is stable or unstable. If the patient is unstable, you need to secure their airway, obtain IV access, and begin resuscitation, as well as monitor and manage their vital signs. Next, obtain a quick focused history and physical exam. Unstable patients with hemothorax typically present with dyspnea and chest pain.

Additionally, they might have a history of an underlying cause, such as chest trauma or recent chest or cardiac procedures like thoracentesis or coronary angiography, as well as a history of cancer, potentially causing erosion into great vessels; thoracic aortic aneurysm; or prior clotting disorders or coagulopathy. On physical examination, you’ll find these patients to be hypotensive and tachycardic. Now, as one side of the chest is full of blood, that lung will be restricted, so you’ll typically find absent unilateral breath sounds. In addition, since that side has no airflow, you might also notice dullness to percussion and decreased tactile fremitus on the affected side.

Okay, because the patient is unstable, you need to act fast! Start by ordering a chest x-ray, which will reveal fluid within the pleural cavity, and can help you rule out several life-threatening conditions. Another quick and reliable way to get an idea of what’s going on is an E-FAST examination. E-FAST involves performing an ultrasound at the bedside to examine the chest and abdominal cavity for the presence of any unusual fluid collection, which typically means blood. If you see fluid within the pleural cavity, suspect a hemothorax.

If this is the case, the first thing you want to do is drain the blood by placing a large bore chest tube, 32 French or greater to prevent tube clotting. Placing the chest tube and releasing the tension will help stabilize most patients. In addition, depending on the severity of the bleed, some patients may need a transfusion. Lastly, you should get emergent surgical consultation, who will manage resuscitation and decide if surgery is needed, such as to explore the thoracic cavity and look for the source of the bleeding.

Now that unstable patients are taken care of, let’s talk about stable patients. Your first step here is to obtain a focused history and physical examination. Similarly to unstable patients, stable ones typically report dyspnea, chest pain, and possibly a history of chest trauma or clotting problems. When it comes to the physical exam, you can expect to find similar findings as before. So, there could be absent unilateral breath sounds, dullness to percussion, and decreased tactile fremitus on the affected side.

Once you’ve obtained both history and physical examination, you should order labs, including a CBC and INR, as well as a chest x-ray. If the labs and chest x-ray are normal, you should consider an alternative diagnosis. On the other hand, labs that point to hemothorax include a normal WBC count, low hemoglobin, and possible low platelets or elevated INR. If you see these lab findings, combined with a chest x-ray that shows opacification of one hemithorax or blunting of one costophrenic angle, suspect the presence of a hemothorax.

Now, this isn’t really enough to make a diagnosis of hemothorax, so you should confirm it with a CT scan of the chest. The CT may show a heterogeneous collection with areas of increased attenuation within the pleural cavity, which is because both fresh and thicker blood clots can attenuate differently on CT. If the CT is with IV contrast, you may see extravasation. If you see these findings on CT, you have confirmed the diagnosis of a hemothorax.

Okay, once the diagnosis of hemothorax is confirmed, start the treatment right away! As before, start by placing the chest tube to drain the collection. After the chest tube has been placed, obtain a follow-up chest x-ray to see if the hemothorax has resolved.