Mediastinal compression due to tension hydrothorax.

We describe a patient in whom a malignant pleural effusion accumulated with sufficient pressure to cause mediastinal compression resulting in acute respiratory distress, dysphagia, and massive edema of the lower extremities. Emergency thoracocentesis produced immediate relief to respiratory symptoms and dysphagia, with gradual disappearance of the edema and a weight loss of 6.8 kg (15 lb) without adjunctive medications. It is suggested that thoracocentesis is a life-saving measure in this circumstance and should be done immediately in patients with similar initial clinical findings, as further diagnostic evaluation or other therapy directed to the mediastinum will not releive the tension and will only delay removal of the fluid.