Pleural Effusion

Question 1

What is a pleural effusion?

Answer 1

• Excessive accumulation of fluid in pleural space.
• Detected on X-Ray ≥300 mL of fluid is present, and clinically, when ≥500 mL is present.
• Fluid below lung can simulate a raised hemidiaphragm

Question 2

What are pleural effusions classified as?

Answer 2

• Transudates
• Exudates

Question 3

How are pleural effusions investigated?

Answer 3

• Ultrasound guided pleural aspiration. Sent for:
  
  • Biochemistry (protein, pH, LDH)
  • Cytology
  • Microbiology
• Consider Thoracoscopy or CT Pleural Biopsy

Question 4

What are Transudates?

Answer 4

• Effusions that are transudates can be bilateral are often larger on right side.
• Protein content is <30 g/L, Lactate dehydrogenase (LDH) is <200 IU/L and Fluid to Serum LDH ratio is <0.6

Question 5

What can causes transduates?

Answer 5

• Heart Failure
• Hypoproteinaemia
• Cirrhosis
• Hypothyroidism
• Mitral Stenosis
• Pulmonary embolism
• Ovarian Tumours producing right-sided pleural effusion (Meigs Syndrome)
• Constrictive Pericarditis

Question 6

What are exudates formed by?

Answer 6

• Protein content of exudates is >30 g/L
• LDH is >200 IU/L.

Question 7

What can cause exudates?

Answer 7

• Bacterial pneumonia
• Carcinoma of bronchus and pulmonary infarction (may be blood stained)
• TB
• Autoimmune rheumatic disease
• Post-myocardial Infarction syndrome
• Acute pancreatitis
• Mesothelioma
• Sarcoidosis
• Yellow-nail syndrome
• Familial Mediterranean fever
• Fungal infection
• Drugs

Question 8

What happens if diagnosis cannot be made by simple aspiration?

Answer 8

Pleural biopsies

Question 9

What is the criteria for diagnosis of exudative fluid in pleural effusion?

Answer 9

Light’s Criteria

Question 10

What is the criteria for Exudative fluid?

Answer 10

• Ratio of pleural fluid protein: serum protein >0.5
• Ratio of pleural fluid LDH: serum LDH >0.6
• Ratio of pleural fluid LDH > 2/3 upper limit of normal for serum (105-333 IU/L)

Question 11

What are radiological investigations of Pleural Effusion?

Answer 11

• X-Ray
• ECG
• Bloods: FBC, U&E’s, LFT’s, CRP, Bone Profile, LDH, Clotting
• Echo: if suspected heart failure
• Staging CT (with contrast) if suspect exudative cause

Question 12

What does X-Ray show for Pleural Effusion?

Answer 12

• Obliteration of costophrenic angle to dense homogenous shadows occupying part or all of hemithorax.
• Fluid in fissures may resemble an intrapulmonary mass

Question 13

What is the management of Pleural Effusion?

Answer 13

• Management of underlying condition unless fluid is purulent
• Intercostal Drain can be used if the fluid is symptomatic.
• Pleurodesis helpful for recurrent infections. Thorascopic mechanical pleurodesis is most effective for Malignant effusion. These are followed by a sclerosing agents such as tetracycline or talc
• Empyema (pus in pleural space) are best drained using a Chest drain under ultrasound or CT guidance

Question 14

What is a Chylothorax?

Answer 14

Due to the accumulation of lymph in the pleural space

Question 15

Why do Chylothraces normally present?

Answer 15

Usually resulting from leakage from the thoracic duct following trauma or infiltration by carcinoma

Question 16

What is the name of Pus in pleural effusions?

Answer 16

Empyema

Question 17

What are the characteristics of Empyemas?

Answer 17

• pH < 7.2
• Low Glucose (< 3.4 mmol/L)
• High LDH (> 200 IU/L or 2-3 times above upper limit of normal range for serum)

Question 18

What are main indication for placing a Chest Tube in Pleural Infection?

Answer 18

• Patients with frankly purulent or turbid/cloudy pleural fluid on sampling should receive prompt pleural space chest tube drainage.
• The presence of organisms identified by Gram stain and/or culture from a non-purulent pleural fluid sample indicates that pleural infection is established and should lead to prompt chest tube drainage.
• Pleural fluid pH < 7.2 in patients with suspected pleural infection indicates a need for chest tube drainage.