Thoracentesis Overview

Thoracentesis is a medical procedure where pleural fluid is removed from the pleural space between the lungs and the chest wall using a needle. This procedure serves both diagnostic and therapeutic purposes.

Indications

• Diagnostic evaluation of pleural effusions
• Relief of symptoms in large effusions (therapeutic)
• Management of complicated pleural effusions
• Evaluation of suspected malignant effusions

Laboratory Analysis

Common tests to order on pleural fluid include:

• Cell count and differential
• Protein and LDH (Light's criteria)
• Glucose
• pH
• Gram stain and culture
• Cytology (if malignancy suspected)

Additional tests to consider:

• Adenosine deaminase (TB)
• Triglycerides (chylothorax)
• NT-proBNP (heart failure)