Pleural effusion: diagnosis and management

Pleural effusion is defined as an accumulation of fluid in the pleural space in excess of 15 to 20 mls. The aetiology for the development of a pleural effusion includes changes in hydrostatic or colloid-osmotic pressure of pleural and pulmonary capillaries, changes in pleural vascular permeability and impaired lymphatic drainage. About 5% to 12% of patients referred for emergency medical treatment are diagnosed with a pleural effusion, making it a common finding on hospital admission. The excess of pleural fluid may be triggered by pleuro-pulmonary infection, malignancy, or conditions of cardiac, renal or hepatic origin. Subsequent management is guided mainly by aetiology and to a lesser degree by symptoms. This paper provides a review of pathophysiology, diagnosis and management of the condition and addresses specific issues regarding the perioperative care of these patients.