Pleural Effusion

Physical Examination

• General examination:

  • Dyspnea: difficulty in breathing

  • Tachypnea: increased respiratory rate

  • Cyanosis: bluish discoloration of lips and nails (in severe cases)

  • Tracheal deviation: away from the affected side (in large effusions)

• Chest inspection:

  • Asymmetric chest expansion: reduced on the affected side

• Palpation:

  • Tactile fremitus: decreased on the affected side

  • Chest wall tenderness: usually absent

• Percussion:

  • Stony dullness: over the area of the effusion

• Auscultation:

  • Diminished breath sounds: over the area of the effusion

  • Pleural rub: may be present if pleuritic inflammation is present (less common)

• Signs of underlying cause

  • Jugular venous distension: congestive heart failure or superior vena cava syndrome

  • Peripheral edema: congestive heart failure, liver cirrhosis, or nephrotic syndrome

  • Lymphadenopathy: cervical or supraclavicular, suggesting malignancy or infection

  • Clubbing: associated with lung cancer, bronchiectasis, or chronic lung abscess

  • Horner's syndrome (ptosis, miosis, anhidrosis): suggestive of Pancoast tumor

  • Signs of connective tissue disease: Raynaud's phenomenon, skin thickening or rashes, joint swelling or deformities (e.g., lupus, rheumatoid arthritis)

  • Signs of pulmonary embolism: tachypnea, tachycardia, pleuritic chest pain, hypoxemia

Investigations

• Laboratory:

  • Complete Blood Count (CBC): can show an elevated white blood cell count in cases of infection.

  • Blood cultures: to identify any bacteria or fungi in the bloodstream.

  • Pleural fluid analysis: includes cell count, glucose, protein, lactate dehydrogenase (LDH), and pH. These can help determine the type of effusion (exudative or transudative) and the underlying cause (infection, malignancy, etc.).

• Imaging:

  • Chest X-ray: can show the presence and extent of the effusion.

  • Ultrasound: to confirm the presence of fluid and help guide diagnostic or therapeutic thoracentesis.

  • Computed tomography (CT) scan: to help evaluate the extent and cause of the effusion.

• Invasive:

  • Thoracentesis: removal of pleural fluid for diagnostic or therapeutic purposes.

  • Pleural biopsy: to obtain tissue samples for analysis if malignancy or tuberculosis is suspected.

  • Video-assisted thoracoscopic surgery (VATS): for diagnosis or treatment of complicated effusions.

• Other tests:

  • Pulmonary function tests: to evaluate underlying lung disease.

  • Echocardiogram: to evaluate for congestive heart failure as a cause of transudative effusions.

  • Tuberculin skin test or interferon-gamma release assay (IGRA): to evaluate for tuberculosis.

Management

General management:

• Identify and treat the underlying cause

• Monitor vital signs and oxygen saturation

• Provide supplemental oxygen if hypoxemic

Medical management:

• Diuretics: for effusions due to congestive heart failure

• Antibiotics: for bacterial pneumonia or empyema

• Anticoagulation: for pulmonary embolism or pleurisy

• Chemotherapy or radiotherapy: for malignant pleural effusions

• Anti-inflammatory drugs: for pleurisy due to connective tissue diseases

Surgical management:

• Thoracentesis: diagnostic (pleural fluid analysis) or therapeutic (fluid removal)

• Indwelling pleural catheter: for recurrent malignant pleural effusions or trapped lung

• Ultrasound or CT-guided drainage: for loculated effusions or difficult access

• Tube thoracostomy (chest drain): for large or symptomatic effusions, empyema, or hemothorax

• Pleurodesis: for recurrent malignant pleural effusions or recurrent pneumothorax

• Decortication: for empyema with trapped lung or loculated effusions

• Pleurectomy: for recurrent malignant pleural effusions

Causes of Pleural Effusion

Transudative Pleural Effusion Causes:

• Congestive heart failure

• Liver cirrhosis

• Nephrotic syndrome

• Hypoalbuminemia

• Peritoneal dialysis

• Pulmonary embolism (rarely)

Exudative Pleural Effusion Causes:

• Parapneumonic effusion (pneumonia)

• Malignancy (lung, breast, lymphoma)

• Tuberculosis

• Pulmonary embolism

• Connective tissue diseases (e.g., lupus)

• Pancreatitis

• Hemothorax

• Chylothorax

• Post-myocardial infarction syndrome

• Asbestos-related pleural disease

Light’s Criteria

Pleural effusion is considered exudative.

• Ratio of pleural fluid protein to serum protein ≥ 0.5

• Ratio of pleural fluid LDH to serum LDH ≥ 0.6

• Pleural fluid LDH ≥ 2/3 upper limit of normal serum LDH