Pleural effusion Flashcards
what is a pleural effusion?
Excess fluid in the pleural cavity resulting in reduced lung expansion and impaired ventilation.
What are the two types of pleural effusion
Transudative and Exudative
What is transudative pleural effusion?
Driven by the obstruction of pulmonary circulation. • Increased intravascular hydrostatic pressure • Decreased intravascular oncotic pressure • These will lead to force inbalance, fluid extraversion, fluid leaks across capillary membranes • Fluid= <25g/L of protein as fluid has to squeeze into pleural space • Occurs due to SYSTEMIC disease
What is exudative pleural effusion?
Occurs as a result of vasoactive mediators from platelet rich clots which increase cell permeability and capillary leakiness. Will occur due to LOCAL disease.
What causes transudative pleural effusions?
Systemic problems. • Increased hydrostatic pressure- heart failure, fluid overload, constrictive pericarditis • Reduced oncotic pressure- low serum albumin due to liver failure, malabsorption/ malnutrition, nephrotic syndrome, end stage renal disease
What causes exudative pleural effusions?
Local problems Infection, malignancy, trauma, pneumonia, TB, primary lung/ metastatic lung malignancy, SLE, rheumatoid arthritis, pancreatitis.
What are the symptoms of pleural effusion?
• Depends on how big the pleural effusion is- small ones may be asymptomatic • Progressive SOB due to limited lung expansion • Pleuritic chest pain (irritation of somatically innervated parietal pleura) • Orthopnoea- SOB may be worse when lying down
What other symptoms should you look out for that could indicate various causes of pleural effusion?
• Fevers, chills, productive cough = pneumonia • Weight loss, loss of appetite = malignancy • Night sweats, travel, haemoptysis= TB • Orthopnoea, tachycardia, peripheral oedema = heart failure • Asbestos = mesothelioma • Joint pain/ rash = autoimmune disease
What signs might you see O/E for pleural effusion
Diminished breath sounds, dullness on percussion. Reduced chest expansion, decreased vocal fremitus, tracheal deviation away from effusion.
State some signs of heart failure you might see
pitting oedema, raised JVP, crackles…
What sort of malignancy signs would you look out for?
clubbing, cachexia, lymphadenopathy, radiation marks, mastectomy
What investigations would you do for one of these patients?
- CXR 2. Lung ultrasound 3. Thoracentesis
What pleural effusion features would you see on a CXR?
- There will be an area of whiteness on the standard PA x-ray
- Blunted costophrenic angles
- Heart and diaphragm borders are obscured
- Forms a concave upper surface that looks like moon crescent -meniscus sign
- If pleural effusion is large enough, there might be mediastinum/ trachea deviation away from the lesion
What is the lung ultrasound (lateral decubitus film) used for?
Detects smaller amount of fluids and can be done at bedside.
Can also identify free flowing (transudative) effusions and loculated (exudative) effusions.
What is thoracentisis?
What is done after fluid is collected?
Send fluid off to lab for clinical chemistry diagnosis.
Look for Amylase, blood, cholesterol, cytology, differential cell count, glucose (if its low), microscopy, low pH, protein/ LDH, triglycerides.
Most importantly, note fluid appearance- serous, bloody, purulent and milk white
