Thoracentesis (Pleural fluid analysis) Normal pleural fluid No pathogens or malignant cells After the patient is positioned in seated, upright position, the lower posterior chest is exposed and prepared, and local anesthesia is given. A needle is inserted into the pleural space, fluid is aspirated To remove fluid from the pleural space for diagnostic or therapeutic reasons. To distinguish between exudates and transdates To identify Tuberculosis,fungal and various bacterial infection, To rule out malignancy Bacterial , viral, or fungal infection Malignancy Collagen disease Lymphoma Systemic Lupus erythematosus Liver failure Nephrotic Syndrome Myxedema Pancreatitis Uncooperative patient