11-2-b-Disorders of the Pleura Lab.txt

• 56-y o woman with a four year history of severe rheumatoid arthritis is evaluated because of chest pain and a persistent left-sded pleural effusion
• High specific gravity: .
• 60%PMNs, high LDH, 20% monocytes, 15% lymphocytes, 5% eosinophils
• Low glucose (47 mg/dL): .

Parietal pleura

Stomata on the parietal pleura of the lower chest wall, low mediastinum and diaphragms that communicate with lymphatics

• Increased interstitial fluid in the lung: increased pulmonary venous pressure (CHF, mitral stenosis, increased permeability of pulmonary vessels[bacterial pneumonia, diffuse alveolar damage, PE, Rheumatoid lung disease])
• Elevation of the systemic venous pressure: right and left ventricular heart failure and superior vena cava syndrome
• Decrease in oncotic pressure in the microvascular circulation: cirrhotic liver diseases, nephritic syndrome, severe protein malnutrition – low serum albumin level in all
• Decreased pleural pressure (increased negative pleural pressure): bronchial obstruction leading to atelectasis
• Movement of fluid from the peritoneal cavity: any condition causing ascites – passage through diaphragmatic lymphatics or diaphragmatic defects

• Obstruction of the lymphatics that drain the parietal pleura: a blockage at any point in the lymphatic system [ tumor or fibrosis]
• Elevation of pressure in the central veins: superior vena cava syndrome and right-sided heart failure

• CHF – transudative
• Bacterial pneumonia – exudative
• Malignant disease – exudative

• PE
• Viral infections
• Cirrhosis, ascites
• GI disease
• Collagen Vascular Disease – Rheumatoid, SLE, Wegener’s granulomatosis
• TB
• Asbestos
• Drugs
• Post-MI
• Meig’s syndrome – ovarian tumor (fibroma) plus right-sided pleural effution

• Fibrinous exudate, some neutrophils and neutrophil debris
• Rheumatoid nodules: nodular aggregates of palisaded histiocytes and fibroblasts that surround central areas of fibrinoid necrosis – CHARACTERISTIC
• Most common thoracic manifestation of rheumatoid disease
• Typically unilateral: .
• Exudative with a high protein level and it usually shows low glucose levels: <50mg/dL and very high LDH
• Male predominance, within 5 years of Rheumatoid arthritis Dx; subcutaneous nodules present: .

Empyema: pus in the pleural space; purulent, complicated parapeumonic effusion in a patient with bacterial pneumonia

• Primary but more commonly metastatic
• Dx: microscopid identification of malignant cells in pleural fluid samples or in pleural tissue biopsies
• Lung carcinoma (30%), breast carcinoma (25%) and lymphomas 20%: .

• Is to establish whether the effusion is a transudate or an exudate by Dx thoracentesis
• Then cell counts, cytology, culture for microorganisms, other tests – glucose, pH, amylase, serologic tests

• Lymphocyte predominance: TB
• PMN predominance: parapneumonic effusions

• Primary spontaneous pneumothorax: most often in tall, thin, young men when an apical subpleural bleb ruptures, smokers; sudden chest pain and dyspnea; most resolve spontaneously
• Secondary spontaneous pneumothorax: removal of air from the pleural space with a chest tube is required and thorascopic surgery to repair the air leak[can be from: COPD (emphysema), PCJ infection in patients with AIDS, eosinophilic granuloma of the lung, necrotizing pneumonias, TB and lymphangiomyomatosis

From penetrating and nonpenetrating chest trauma

• High incidence
• Major causes: transthoracic needle aspiration, subclavian needle stick, thoracentesis, pleural biopsy, positive pressure ventilation

Whe the defect that connects the air-filled lung to the pleural space acts as a flap valve that permits air to enter the pleura during inspiration, but fails o permit its escape during expiration

• Presence of significant blood in the pleural space
• Hematocrit at least 50% of the peripheral blood