Pleural effusion ppt

Pleural effusion is an accumulation of fluid in the pleural cavity


between the lining of the lungs and the thoracic cavity (i.e., the visceral

and parietal pleurae


).

1. physiology Pathology Management Pleural Effusion

2. Pleural Fluid: Pleural space normally contains 5-10 ml of pleural fluid. This lubricates the apposing surfaces of the visceral & parietal pleurae during respiratory movements. It is formed by presence of hydrostatic & osmotic pressures. Excreted via parietal pleura capillaries ( higher hydrostatic pressure ) and absorbed into the capillaries of visceral pleura ( lower hydrostatic pressure ). Any condition that increases production or impairs drainage of fluid results in abnormal accumulation in pleural space between lining of the lungs & thoracic cavity, known as pleural – effusion .

3. Pleural Effusion: Pleural effusion is a common manifestation of both primary & secondary pleural diseases, which may be inflammatory or non-inflammatory. Accumulation of pleural fluid is not a specific disease, but rather a reflection of underlying pathology. Source of the fluid is usually blood vessels or lymphatic vessels lying beneath either pleura, but occasionally an abscess or other lesion may drain into pleural space. Can occur in the following setting: Increased hydrostatic pressure : as in congestive heart failure. Increased vascular permeability : as in pneumonia. Decreased osmotic pressure : as in nephrotic syndrome. Increased intrapleural negative pressure: as in atelectasis. Decreased lymphatic drainage : as in mediastinal carcinomatosis.

4. Pleural Effusion: Transudate is a filtrate, hence, it is a clear fluid with a low protein & cell count. Exudate, on the other hand, is a cloudy fluid with a high protein & cell count; as lesions responsible for the outflow of exudate allow larger molecules & even solid matter to pass into the pleural space. The effusion follows gravity & usually collects in the lower margins of the pleural space.

5. Pleural Fluid: Generally, fluid accumulates as a result of: Increased hydrostatic pressure or decreased osmotic pressure ( “transudative” effusion ). Increased microvascular pressure due to disease of the pleural surface itself or injury in the adjacent lung ( “exudative” effusion ).

6. Etiology: Common causes: Pneumonia Cardiac failure Subdiaphragmatic disorders (subphrenic abscess, pancreatitis, etc.) Tuberculosis Pulmonary infarction Malignant disease Uncommon causes: Hypoproteinaemia (nephrotic syndrome, liver failure, malnutrition). Connective tissue disorder (SLE, rheumatoid arthritis) Acute rheumatic fever Post-myocardial infarction syndrome. Myxoedema Uraemia Meigs’ syndrome (ovarian tumor + plural effusion) Asbestos-related.

7. Clinical Features: Pain on inspiration + coughing/sneezing. Pleuritic chest pain. May be localized or referred. Non-productive cough. Breathlessness (dyspnea) is the only symptom related to the effusion itself, & its severity depends on the size & rate of accumulation. Inspection: Tachypnoea Palpation: Decreased chest expansion on affected side. Trachea & apex may be shifted towards unaffected side. Reduced tactile vocal fremitus. Percussion: Stony dull tone. Usually the R mid- and lower- zones. Auscultation: Absent breath sounds Diminished or absent vocal resonance at affected side. Crackles above effusion.

8. Diagnosis: The diagnostic evaluation of pleural effusion includes: chemical microbiological studies as well as cytological analysis, which can provide further information about the etiology of the disease process. Immunohistochemistry provides increased diagnostic accuracy.

9. Imaging: Chest x-ray & ultrasound are usually performed as first-line tests to diagnose pleural effusion. Standard PA & lateral views remain the most important technique for initial diagnosis of pleural effusion . But thorax CT is sometimes required (e.g. for very small effusions).

10. Imaging: CXR : Around 200 mL of fluid is required to be detectable on a PA chest x-ray. Smaller effusions can be identified by ultrasound or CT . Classical appearance of pleural fluid on the erect PA chest film is of a curved shadow at the lung base, blunting the costophrenic angle & ascending towards the axilla. Previous scarring or adhesions in the pleural space can cause localized effusions. Fluid localized within an oblique fissure may produce a rounded opacity, simulating a tumour.

11. Imaging - CXR: X-ray chest, PA view, with fissural effusion. X-ray chest, lateral view, with fissural effusion.

12. Imaging: Ultrasonography : Is more accurate than plain CXR for determining the volume of pleural fluid & frequently provides additional helpful information. Visualisation of fluid facilitates skin marking to indicate a site for safe needle aspiration & guides pleural biopsy, increasing diagnostic yield. Technique may also distinguish pleural fluid from pleural thickening. CT : Displays pleural abnormalities more readily than either plain radiography or ultrasound, & may distinguish benign from malignant pleural disease.

13. Imaging – CT thorax: Contrast-enhanced computed tomography: split pleural sign Split pleural sign refers to thickening & increased contrast enhancement of the visceral & parietal pleura separated by empyema or an exudative effusion.

14. Pleural aspiration & biopsy: In most cases, sampling is necessary to establish a diagnosis. Is the PREFERRED investigation (pleural tap). Simple aspiration provides information on the color & texture of fluid & on appearance alone may immediately suggest an empyema or chylothorax. Presence of blood consistent with pulmonary infarction or malignancy , but may also represent a traumatic tap . Gram stain of pleural fluid may indicate para-pneumonic effusion. Cytological examination is essential . A low pH suggests infection, but also seen in rheumatoid arthritis , ruptured oesophagus or advanced malignancy .

15. Pleural aspiration & biopsy: Aspiration should not be performed for bilateral effusions in a clinical setting strongly suggestive of a pleural transudate. Differentiation between transudate & exudate is crucial before further tests are undertaken. Hemorrhagic effusions can be differentiated from traumatic pleural taps by observing serial samples of pleural tap which clear up in the case of a traumatic pleural tap. The routine pleural fluid evaluation usually includes determination of: Protein pH Lactate dehydrogenase (LDH). Glucose & albumin levels, with adenosine deaminase levels Cell count for differential & cytological examination.

16. Pleural Fluid Analysis: Light’s criteria ( transudate vs. exudate ): Pleural fluid is an exudate if ONE or MORE of the following criteria are met: Pleural fluid protein : serum protein ratio > 0.5 Pleural fluid LDH : serum LDH ratio > 0.6 Pleural fluid LDH > two-thirds of the upper limit of normal serum LDH. NB: *LDH – lactate dehydrogenase.

17. Malignant Pleural Effusion: Is a common complication of cancer. 40% of all pleural effusions are due to malignancy. Most common causes are lung & breast cancers, & presence of effusion indicates advanced & incurable disease. Pleural aspirate is the key investigation & may show malignant cells. In fact, the most common diagnosis with a massive effusion is malignancy, other causes being complicated parapneumonic effusions & tuberculosis.

18. Differential Diagnoses: Bacterial pneumonia. Pulmonary thromboembolism (pulmonary infarct). Carcinoma. Connective tissue disorder. TB.

19. Management: To treat pleural effusion appropriately, it is important to determine its etiology. However, the etiology of pleural effusion remains unclear in nearly 20% of cases. First of; stabilize patients with respiratory distress. Therapeutic aspiration may be required to palliate breathlessness. An effusion should never be drained to dryness before establishing a diagnosis. Treatment of underlying cause – for example, heart failure, pneumonia, pulmonary embolism or subphrenic abscess – will often be followed by resolution of the effusion.

20. Treat U nderlying Cause: Acute congestive heart failure – loop diuretics. Collagen vascular diseases – steroids. Pancreatitis. Pancreaticopleural fistula – endoscopic or surgical intervention is recommended. Meigs syndrome – removal of ovarian tumor is recommended. Other malignancy: targeted cancer immunotherapy, chemotherapy, radiotherapy, or surgical resection.