Pleural Effusion Flashcards Preview

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Flashcards in Pleural Effusion Deck (10)
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1
Q

What is the best imaging for a pleural effusion?

A
  • plain chest radiograph, PA

- ultrasound recommended, helps with aspiration

2
Q

How should fluid be aspirated and what should be done with it?

A
  • ultrasound is recommended to reduce the complication rate
  • a 21G needle and 50ml syringe should be used
  • fluid should be sent for pH, protein, lactate dehydrogenase (LDH), cytology and microbiology
3
Q

What about the fluid from a pleural effusion needs to be determined?

A

Distinguis between transudate and exudate

Light’s criteria was developed in 1972 to help distinguish between a transudate and an exudate. The BTS recommend using the criteria for borderline cases:

  • exudates have a protein level of >30 g/L, transudates have a protein level of 0.5
    2) pleural fluid LDH divided by serum LDH >0.6
    3) pleural fluid LDH more than two-thirds the upper limits of normal serum LDH
4
Q

What are the leading causes of pleural effusion?

A
  • Congestive heart failure (transudate), incidence 500,000/year
  • Pneumonia (exudate), incidence 300,000/year
  • Cancer (exudate), incidence 200,000/year
  • Pulmonary embolus (transudate or exudate), incidence 150,000/year
  • Viral disease (exudate), incidence 100,000/year
  • Coronary-artery bypass surgery (exudate), incidence 60,000/year
  • Cirrhosis with ascites (transudate), incidence 50,000/year
5
Q

What are the causes of an exudative pleural effusion?

A
  • Abdominal fluid: Abscess in tissues near lung, ascites, Meigs syndrome, pancreatitis
  • Connective-tissue disease: Churg-Strauss disease, lupus, rheumatoid arthritis, Wegener granulomatosis
  • Endocrine: Hypothyroidism, ovarian hyperstimulation
  • Iatrogenic: Drug-induced, esophageal perforation, feeding tube in lung
  • Infectious: Abscess in tissues near lung, bacterial pneumonia, fungal disease, parasites, tuberculosis
  • Inflammatory: Acute respiratory distress syndrome (ARDS), asbestosis, pancreatitis, radiation, sarcoidosis, uremia
  • Lymphatic abnormalities: Chylothorax, malignancy, lymphangiectasia
  • Malignancy: Carcinoma, lymphoma, leukemia, mesothelioma, paraproteinemia
6
Q

What are the causes of a transudative pleural effusion?

A
  • Atelectasis: Due to increased negative intrapleural pressure
  • Cerebrospinal fluid (CSF) leak into pleural space: Thoracic spine injury, ventriculoperitoneal (VP) shunt dysfunction
  • Heart failure
  • Hepatic hydrothorax
  • Hypoalbuminemia
  • Iatrogenic: Misplaced catheter into lung
  • Nephrotic syndrome
  • Peritoneal dialysis
  • Urinothorax: Due to obstructive uropathy
7
Q

How does a transudate pleural effusion arise?

A

Transudates are usually bilateral and arise from either increased capillary hydrostatic pressure or decreased oncotic pressure secondary to congestive heart failure, fluid overload, cirrhosis or hypoalbuminemia.

8
Q

How does an exudate pleural effusion arise?

A

Exudates are usually unilateral and result from increased capillary permeability or decreased lymphatic resorption associated with infection, connective tissue disease, pancreatitis or cancer.

9
Q

What is the protocol with suspected infection in a pleural effusion?

A
  • all patients with a pleural effusion in association with sepsis or a pneumonic illness require diagnostic pleural fluid sampling
  • if the fluid is purulent or turbid/cloudy a chest tube should be placed to allow drainage
  • if the fluid is clear but the pH is less than 7.2 in patients with suspected pleural infection a chest tube should be placed
10
Q

What are some characteristic features about the fluid in pleural effusions that could help point to a diagnosis?

A
  • low glucose: rheumatoid arthritis, tuberculosis
  • raised amylase: pancreatitis, oesophageal perforation
  • heavy blood staining: mesothelioma, pulmonary embolism, tuberculosis