This document summarizes pleural effusions, including their anatomy, mechanisms, etiologies, clinical presentations, diagnostic approaches, and management strategies. Pleural effusions can be caused by conditions that elevate pleural pressures or permeability. A diagnostic thoracentesis is usually needed to determine if an effusion is a transudate or exudate and identify the underlying cause. Management depends on the etiology but may include antibiotics, drainage, or anti-tuberculosis therapy.

1. Pleural Effusions Can-mao Xie Dept. of Pulmonary & Critical Care Medicine 1 st Affiliated Hospital of Sun-Yat Sen University Dr. Canmao xie

7. Figure 1. Anatomy of the pleural space SC: Systemic capillaries PC: Pulmonary capillaries Dr. Canmao xie stomas stomas electronic microscopy

8. Figure 2. pleural fluids turnover PF enter the pleural space through parietal & visceral pleurae, And leave pleural space through lymphatics in parietal pleura Dr. Canmao xie

10. Figure. Diagrammatic representation of the pressures involved in the formation and absorption of pleural fluid. Parietal Pleura Visceral Pleura Space Pleura Hydrostatic Pressure + 30 - 5 + 24 35 29 6 0 Net 29 29 + 34 + 5 +34 Oncotic Pressure Dr. Canmao xie

18. A posteroanterior and lateral chest radiograph of pleural effusion blunting of the posterior costophrenic angle Dr. Canmao xie

21. Light RW. Clin Chest Med, 2006,27:309-319 Etiology of pleural effusions

25. Dr. Canmao xie

32. Malignant effusions Dr. Canmao xie

33. 肺腺癌 患者男性， 65 岁。 因“反复胸痛 5 月，呼吸困难 1 月，加重 1 周” 入院。胸水 CEA 增高。 镜下见：脏、壁层胸膜间粘连带形成，壁层胸膜、膈面见弥漫性结节样新生物，部分表面覆盖白色坏死组织，右上叶后段斜裂缘见白色息肉样肿物，右下叶表面多发灰色斑状浸润。病理示腺癌。

37. Tuberculous Pleurisy Dr. Canmao xie

42. Thank you for attention! Dr. Canmao xie