Pleural effusions. 1. Preliminary evaluation--recognition of the transudate.

Part 1 of this two-part article describes how to document the presence and location of pleural effusion, perform thoracentesis, and differentiate transudates from exudates. If the pleural fluid is found to be a transudate, no further tests are indicated. Part 2, starting on page 181, details pleural fluid analysis, describes pleural biopsy and thoracoscopy, and presents a clinical strategy for evaluating pleural effusion.