Pleural effusion

1. Pleural effusion by Dr.esraa dozan

2. definitions A pleural effusion is an abnormal collection of fluid in the pleural space resulting from excess fluid production or decreased absorption or both. It is the most common manifestation of pleural disease. Hemothorax is blood in plueral space . Chylothorax is chyle ( lymph+fat ) in pleural spcae . Empyema is pus in plueral space .

3. Anatomy The pleural space is bordered by the parietal and visceral pleurae. The parietal pleura covers the inner surface of the thoracic cavity, including the mediastinum , diaphragm, and ribs. The visceral pleura envelops all lung surfaces, including the interlobar fissures. The right and left pleural spaces are separated by the mediastinum .

4. The pleural space plays an important role in respiration by coupling the movement of the chest wall with that of the lungs in 2 ways. First , a relative vacuum in the space keeps the visceral and parietal pleurae in close proximity. Second, the small volume of pleural fluid, which has been calculated at 0.13 mL /kg of body weight under normal circumstances, serves as a lubricant to facilitate movement of the pleural surfaces against each other in the course of respirations.

5. Etiology Pleural effusion is an indicator of an underlying disease process that may be pulmonary or nonpulmonary in origin and may be acute or chronic. Although the etiologic spectrum of pleural effusion is extensive, most pleural effusions are caused by congestive heart failure, pneumonia, malignancy, or pulmonary embolism

6. The following mechanisms play a role in the formation of pleural effusion: Reduction in intravascular oncotic pressure ( eg , hypoalbuminemia due to nephrotic syndrome or cirrhosis ) Increased capillary permeability or vascular disruption ( eg , trauma, malignancy, inflammation, infection, pulmonary infarction, drug hypersensitivity, uremia, pancreatitis)

7. Increased capillary hydrostatic pressure in the systemic and/or pulmonary circulation ( eg , congestive heart failure ) Reduction of pressure in the pleural space, preventing full lung expansion or "trapped lung" ( eg , extensive atelectasis , mesothelioma ) Decreased lymphatic drainage or complete blockage, including thoracic duct obstruction or rupture ( eg , malignancy, trauma)

8. Increased peritoneal fluid, with migration across the diaphragm via the lymphatics or structural defect ( eg , cirrhosis, peritoneal dialysis) Movement of fluid from pulmonary edema across the visceral pleura Altered permeability of the pleural membranes ( eg , inflammation, malignancy, pulmonary embolus)

9. Pleural effusions are generally classified as transudates or exudates, based on the mechanism of fluid formation and pleural fluid chemistry. Transudates result from an imbalance in oncotic and hydrostatic pressures, whereas exudates are the result of inflammation of the pleura or decreased lymphatic drainage.

10. Transudates Transudates causes include the following: Congestive heart failure Cirrhosis (hepatic hydrothorax) Atelectasis - Which may be due to malignancy or pulmonary embolism Hypoalbuminemia Nephrotic syndrome Myxedema Constrictive pericarditis

11. Urinothorax - Usually due to obstructive uropathy Cerebrospinal fluid (CSF) leaks to the pleura - Generally in the setting of ventriculopleural shunting or of trauma or surgery to the thoracic spine Duropleural fistula - Rare, but may be a complication of spinal cord surgery Extravascular migration of central venous catheter Glycinothorax - A rare complication of bladder irrigation with 1.5% glycine solution following urologic surgery

12. Exudates common causes of exudates include the following: Tuberculosis Parapneumonic . Malignancy (most commonly lung or breast cancer, lymphoma, and leukemia; less commonly ovarian carcinoma, stomach cancer, sarcomas, melanoma) Pulmonary embolism Collagen-vascular conditions (rheumatoid arthritis, systemic lupus erythematosus ) Pancreatitis

13. Trauma Esophageal perforation Radiation pleuritis Sarcoidosis Fungal infection Intra-abdominal abscess Meigs syndrome (benign pelvic neoplasm with associated ascites and pleural effusion) Yellow nail syndrome (yellow nails, lymphedema , pleural effusions

14. Drug-induced pleural disease: Isoniazide . procainamide hydralazine quinidine nitrofurantoin methotrexate

15. Presentation The clinical manifestations of pleural effusion are variable and often are related to the underlying disease process: Dyspnea : is the most common symptom associated with pleural effusion. Cough: in patients with pleural effusion is often mild and nonproductive. More severe cough or the production of purulent or bloody sputum suggests an underlying pneumonia or endobronchial lesions

16. Chest pain : which results from pleural irritation, raises the likelihood of an exudative etiology, such as pleural infection, mesothelioma , or pulmonary infarction. Additional symptoms Other symptoms in association with pleural effusions may suggest the underlying disease process. Increasing lower extremity edema, orthopnea , and paroxysmal nocturnal dyspnea may all occur with congestive heart failure. Night sweats, fever, hemoptysis , and weight loss should suggest TB . Hemoptysis also raises the possibility of malignancy, other endotracheal or endobronchial pathology, or pulmonary infarction. An acute febrile episode, purulent sputum production, and pleuritic chest pain may occur in patients with an effusion associated with pneumonia

17. WORKUP History . Examination: decreased expansion. Stony dull percussion note. Diminished breath sounds. Decreased tactile vocal fremitus and resonance. Singns of underlying disease.

18. Investigatios : Chest radiology and ultrasonography Diagnostic aspiration Additional tests.

19. Chest Radiography Effusions of more than 175 mL are usually apparent as blunting of the costophrenic angle on upright posteroanterior chest radiographs. On supine chest radiographs, which are commonly used in the intensive care setting, moderate to large pleural effusions may appear as a homogenous increase in density spread over the lower lung fields. Apparent elevation of the hemidiaphragm , lateral displacement of the dome of the diaphragm, or increased distance between the apparent left hemidiaphragm and the gastric air bubble suggests subpulmonic effusions.

20. Anteroposterior , upright chest radiograph shows bilateral pleural effusions and loss of bilateral costophrenic angles (meniscus sign).

21. Posteroanterior , upright chest radiograph shows isolated, left-sided pleural effusion and loss of left, lateral costophrenic angle.

22. Lateral decubitus films more reliably detect smaller pleural effusions. Layering of an effusion on lateral decubitus films defines a freely flowing effusion and, if the layering fluid is 1 cm thick, indicates an effusion of greater than 200 mL that is amenable to thoracentesis . Failure of an effusion to layer on lateral decubitus films indicates the presence of loculated pleural fluid or some other etiology causing the increased pleural density.

23. CT Scanning and Ultrasonography Chest CT scanning with contrast should be performed in all patients with an undiagnosed pleural effusion, if it has not previously been performed, to detect thickened pleura or signs of invasion of underlying or adjacent structures. The two diagnostic imperatives in this situation are pulmonary embolism and tuberculous pleuritis . In both cases, the pleural effusion is a harbinger of potential future morbidity. In contrast, a short delay in diagnosing metastatic malignancy to the pleural space has less impact on future clinical outcomes. CT angiography should be ordered if pulmonary embolism is strongly suggested

24. Diagnostic Thoracentesis A diagnostic thoracentesis should be performed under ultrasound guide if the etiology of the effusion is unclear or if the presumed cause of the effusion does not respond to therapy as expected. Relative Relative Contraindications : small volume of fluid (< 1 cm thickness on a lateral decubitus film) bleeding diathesis or systemic anticoagulation mechanical ventilation cutaneous disease over the proposed puncture site.

25. Reversal of coagulopathy or thrombocytopenia may not be necessary as long as the procedure is performed under ultrasound guidance by an experienced operator.Mechanical ventilation with positive end-expiratory pressure does not increase the risk of pneumothorax after thoracentesis , but it increases the likelihood of severe complications (tension pneumothorax or persistent bronchopleural fistula) if the lung is punctured. An uncooperative patient is an absolute contraindication for this procedure.

26. Complications pain at the puncture site cutaneous or internal bleeding from laceration of an intercostal artery or spleen/liver puncture pneumothorax , empyema , reexpansion pulmonary edema, malignant seeding of the thoracentesis tract, and adverse reactions to anesthetics used in the procedure. Pneumothorax complicates approximately 6% of thoracenteses but requires treatment with a chest tube drainage of the pleural space in less than 2% of cases. In addition, significant chronic obstructive or fibrotic lung disease increases the risk of a symptomatic pneumothorax complicating the thoracentesis

27. When a pleural fluid sample is taken it should be analysed as follows:

28. Distinguishing Transudates From Exudates the tests first proposed by Light have become the criterion standards: The fluid is considered an exudate if any of the following are found: Ratio of pleural fluid to serum protein greater than 0.5 Ratio of pleural fluid to serum LDH greater than 0.6 Pleural fluid LDH greater than two thirds of the upper limits of normal serum value

29. The fluid is considered a transudate if all of the above are absent alternative criteria : Pleural fluid LDH value greater than 0.45 of the upper limit of normal serum values Pleural fluid cholesterol level greater than 45 mg/ dL Pleural fluid protein level greater than 2.9 g/ dL Pleural fluid cosidered exudate if protein content is more than 35g/l and transudate if less than 25g/l.

30. pitfalls The criteria from Light and these alternative criteria identify nearly all exudates correctly, but they misclassify approximately 20-25% of transudates as exudates, usually in patients on long-term diuretic therapy for congestive heart failure (because of the concentrating effect of diuresis on protein and LDH levels within the pleural space).

31. Using the criterion of serum minus pleural protein concentration level of less than 3.1 g/ dL , rather than a serum/pleural fluid ratio of greater than 0.5, more correctly identifies exudates in these patients. A gradient of serum albumin to pleural fluid albumin of less than 1.2 g/ dL also identifies an exudate in such patients.

32. Pleural Fluid LDH, Glucose, and pH Pleural fluid LDH levels greater than 1000 IU/L suggest empyema , malignant effusion, rheumatoid effusion, or pleural paragonimiasis . Pleural fluid LDH levels are also increased in effusions from Pneumocystis jiroveci (formerly, P carinii ) pneumonia. The diagnosis is suggested by a pleural fluid/serum LDH ratio of greater than 1, with a pleural fluid/serum protein ratio of less than 0.5. ???????????

33. Pleural fluid glucose and pH A low pleural glucose concentration (30-50 mg/ dL ) suggests malignant effusion, tuberculous pleuritis , esophageal rupture, or lupus pleuritis . A very low pleural glucose concentration ( ie , < 30 mg/ dL ) further restricts diagnostic possibilities, to rheumatoid pleurisy or empyema . Pleural fluid pH is highly correlated with pleural fluid glucose levels. A pleural fluid pH of less than 7.30 with a normal arterial blood pH level is caused by the same diagnoses as listed above for low pleural fluid glucose. However, for parapneumonic effusions, a low pleural fluid pH level is more predictive of complicated effusions (that require drainage) than is a low pleural fluid glucose level. In such cases, a pleural fluid pH of less than 7.1-7.2 indicates the need for urgent drainage of the effusion, while a pleural fluid pH of more than 7.3 suggests that the effusion may be managed with systemic antibiotics alone.

34. Light’s criteria for parapneumonic effusions : Indications of thoracostomy in parapneumonic effusion: a low pleural fluid glucose level (<40 mg/ dL ), a low. or pleural fluid pH (<7.2) or a positive Gram stain or Positive culture of the pleural fluid are more likely to require tube thoracostomy .

35. In malignant effusions, a pleural fluid pH of less than 7.3 has been associated in some reports with more extensive pleural involvement, higher yield on cytology, decreased success of pleurodesis , and shorter survival times. Handle pleural fluid samples as carefully as arterial samples for pH measurements, with fluid collected in heparinized syringes and ideally transported on ice for measurement within six hours.

36. Pleural Fluid Cell Count Differential Pleural fluid lymphocytosis , with lymphocyte values greater than 85% of the total nucleated cells, suggests TB, lymphoma, sarcoidosis , chronic rheumatoid pleurisy. Pleural lymphocyte values of 50-70% of the nucleated cells suggest malignancy Pleural fluid eosinophilia with values greater than 10% of nucleated cells, is seen in approximately 10% of pleural effusions and is not correlated with peripheral blood eosinophilia.and is most often caused by air or blood in the pleural space.

37. Blood in the pleural space causing eosinophilia may be the result of pulmonary embolism with infarction or benign asbestos pleural effusion or may be associated with other nonmalignant diseases, including parasitic disease (especially paragonimiasis ), fungal infection ( coccidioidomycosis , cryptococcosis , histoplasmosis ), and a variety of medications. High neutrophil count in pleural fluid suggests parapneumonic effusion.

38. Pleural Fluid Cytology Cytology findings(abnormal mesothelial cell) are positive in 58% of effusions related to mesothelioma . The sensitivity of cytology is not highly related to the volume of pleural fluid tested. Sending more than 50-60 mL of pleural fluid for cytology does not increase the yield of analysis.

39. Additional Laboratory Tests Additional specialized tests are warranted when specific etiologies are suspected. Pleural biopsy. Measure pleural fluid amylase levels if a pancreatic origin or ruptured esophagus is suspected or if a unilateral, left-sided pleural effusion remains undiagnosed after initial testing. note, increased pleural fluid amylase can also be seen with malignancy. Measure triglyceride and cholesterol levels in milky pleural fluids when chylothorax or pseudochylothorax is suspected.

40. Tumor markers, such as carcinoembryonic antigen, are suggestive of malignant effusions (especially adenocarcinoma ). Consider immunologic studies, including pleural fluid antinuclear antibody(SLE) and rheumatoid factor (RA), when collagen-vascular diseases are suspected.

41. Treatment Transudative effusions are managed by treating the underlying medical disorder. However, regardless of whether transudative or exudative , large, refractory pleural effusions causing severe respiratory symptoms can be drained to provide symptomatic relief. The management of exudative effusions depends on the underlying etiology of the effusion. Pneumonia, malignancy, and TB cause most exudative pleural effusions. Complicated parapneumonic effusions and empyemas should be drained to prevent development of fibrosing pleuritis . Malignant effusions are usually drained to palliate symptoms and may require pleurodesis to prevent recurrence.

42. Surgery : pesistanat collections +pleural thickning on u/s may require surgical intervention.

43. THANK YOU