Pleural Effusion

The pleura are two thin, moist membranes around the lungs. The inner layer is attached to the lungs. The outer layer is attached to the ribs. Pleural effusion is the buildup of excess fluid in the space between the pleura. The fluid can prevent the lungs from fully opening. This can make it difficult to catch your breath. Pleural effusion may be watery (transudative) or thick (exudative) based on the cause. Treatment of pleural effusion depends on the condition causing the effusion.

  • Causes

    Effusion is usually caused by disease or injury.

    Transudative effusion may be caused by:

    • Heart failure
      or pericarditis
    • Pulmonary embolism
    • Malnutrition
    • Liver diseasePancreatitis
    • Kidney disease
    • A large shift in body fluids

    Exudative effusion may be caused by:

    • Tuberculosis
    • Pneumonia
      and other lung infections

    • Rheumatic disease, such as
      sarcoidosis
    • Anti-inflammatory diseases, such as Lupus
    • Cancer, especially of the
      lung,
      breast, or lymph system


    • Blood clot formation in the lung

  • Definition

    The pleura are two thin, moist membranes around the lungs. The inner layer is attached to the lungs. The outer layer is attached to the ribs. Pleural effusion is the buildup of excess fluid in the space between the pleura. The fluid can prevent the lungs from fully opening. This can make it difficult to catch your breath.

    Pleural effusion may be watery (transudative) or thick (exudative) based on the cause. Treatment of pleural effusion depends on the condition causing the effusion.

    Pleural Effusion
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  • Diagnosis

    The doctor will ask about your symptoms and medical history. A physical exam will be done. This may include listening to or tapping on your chest. Lung function tests will test your ability to move air in and out of your lungs.

    Some blood tests will be done based on what the doctor thinks it causing the fluid.

    Images of your lungs may be taken with:

    • Chest x-ray
    • Ultrasound
    • CT scan

    Your doctor may take samples of the fluid or pleura tissue for testing. This may be done with:

    • Thoracentesis
    • Biopsy
    • Thoracoscopy

  • Prevention

    Prompt treatment for any condition that may lead to effusion is the best way to prevent pleural effusion.

  • Risk Factors

    Factors that increase your chance of getting pleural effusion include:

    • Having conditions or diseases listed above

    • Certain medications such as:

      • Nitrofurantoin
      • Methysergide
      • Bromocriptine
      • Procarbazine
      • Amiodarone
    • Chest injury or trauma
    • Radiation therapy

    • Surgery, especially involving:

      • Heart
      • Lungs
      • Abdomen
      • Organ transplantation

  • Symptoms

    Some types of pleural effusion do not cause symptoms. Others cause a variety of symptoms, including:

    • Shortness of breath
    • Chest pain
    • Stomach discomfort
    • Cough
    • Coughing up blood
    • Shallow breathing
    • Rapid pulse or breathing rate
    • Weight loss
    • Fever, chills, or sweating
    • Hiccupping

    These symptoms may be caused by many other conditions. Let your doctor know if you have any of these symptoms.

  • Treatment

    Treatment is usually aimed at treating the underlying cause. This may include medications or surgery.

    Your doctor may take a "watchful waiting" approach if your symptoms are minor. You will be monitored until the effusion is gone.