Does the clinical picture suggest a transudate (e.g. LVF, hypoalbuminaemia, dialysis)?
It is often possible to identify transudative effusions by clinical assessment alone. • If YES, treat the cause. This may result in resolution. If it doesn’t, continue with pleural aspiration, as below. • If NO, perform pleural aspiration. (Please see separate article Pleural Effusion Aspiration). Ultrasound-guided pleural aspiration may be needed if the effusion is small or loculated. • Pleural aspiration (thoracentesis): send aspirated fluid for cytology; protein; lactate dehydrogenase (LDH); pH; Gram stain, culture and sensitivity; acid-alcohol fast bacilli (AAFB) stains and culture. • Do you suspect an empyema, chylothorax or haemothorax (because of the appearance/odour of the fluid)? • If YES, perform additional pleural fluid tests: • For empyema: centrifuge to differentiate from chylothorax • For chylothorax: cholesterol and triglyceride levels; centrifuge; presence of cholesterol crystals and chylomicrons • For haemothorax: haematocrit • Perform other tests as appropriate: for e
