Pleural effusion: Clinical

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Pleural effusion: Clinical

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A 47-year-old female comes to the emergency department with shortness of breath and cough. The patient’s symptoms have gradually worsened over the past several months. She has no prior medical diagnoses, but she does consume alcohol regularly and has a 15-pack-year smoking history. Family history is notable for coronary artery disease, type II diabetes mellitus, and a sister who carries the BRCA gene mutation. Temperature 37.6°C (99.7°F), pulse is 105/min, and blood pressure is 140/67 mmHg. Respiratory rate is 21/min, and oxygen saturation is 90% on room air. Physical examination is notable for absent breath sounds on the right with dullness to percussion. Non-tender lymphadenopathy is noted at the right axilla. Which of the following is the next best step in the management of this patient?

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Our lungs are covered by two layers of pleura, the inner visceral pleura, and the outer parietal pleura.

Sandwiched between these layers is the pleural space, which normally contains about 10 milliliters of fluid and that provides a bit of lubrication, so that the lungs can smoothly expand within the chest cavity without encountering much friction.

Too much fluid in that space results in a pleural effusion, which can actually hinder lung expansion.

Now, pleural effusions can be broadly classified into transudative and exudative effusions.

Transudative effusions are often caused by systemic diseases, and result from either an increase in the intravascular hydrostatic pressure, such as in congestive heart failure, or as a result of a decrease in the intravascular oncotic pressure due to a decrease in serum albumin, like in liver cirrhosis, nephrotic syndrome, or malnutrition.

Exudative effusions, on the other hand, are usually due to local diseases that may cause inflammation, resulting in increased capillary permeability.

These include infections like pneumonia or tuberculosis, primary lung or metastatic malignancy, autoimmune diseases like systemic lupus erythematosus or rheumatoid arthritis, or pancreatitis.

One more specific type of effusion is a chylothorax, and it results from impaired lymphatic drainage of the pleura, which can happen after accidental damage during surgery, trauma, or cancer invasion.

Interestingly, pulmonary embolism can cause both transudative and exudative effusions.


Pleural effusion refers to the accumulation of fluid in the pleural cavity. This fluid can impede the lungs' movement and make it difficult to breathe. There are various kinds of pleural effusion, depending on the nature of the fluid and what caused its entry into the pleural space. Pleural effusion can be hydrothorax (serous fluid), hemothorax (blood), urinothorax (urine), chylothorax (chyle), or pyothorax (pus).

Transudative pleural effusion contains decreased protein content and is usually due to increased hydrostatic pressure. Exudative pleural effusion contains increased protein content and is commonly due to malignancy, pneumonia, collagen vascular disease, or trauma.

Diagnosis may require thoracentesis which can help alleviate symptoms, a chest X-ray, or a CT scan. Treatment depends on the underlying cause and may involve antibiotics for infection, chemotherapy if the cause was cancer, and managing the heart or renal failure if they are the underlying causes.


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