1. Pleural Effusions

2. The Pleura

3. Pleural Pathophysiology
Transpleural pressure imbalance
Increased capillary permeability
Impaired lymphatic drainage
Transdiaphragmatic movement of fluid
Pleural effusions of extravascular origin (chylothorax)

4. On CXR

5. Differential Diagnosis
Transpleural pressure imbalance
CHF
Increased capillary permeability
PNA
Impaired lymphatic drainage
Malignancy
Late PNA (fibrin)
Transdiaphragmatic movement of fluid
Hepatic Hydrothorax
Peritoneal dialysis
Pleural effusions of extravascular origin (chylothorax)

6. Differential Diagnosis - Complete
CHF
Hepatic Hydrothorax PD
Pancreatitis
Lung/Liver abscess
Chylous ascites
Malignancy
Meig’s syndrome (ascites, benign ovarian tumor)
Parapneumonic
Pulmonary embolism TB
Hypoalbuminemia/Nephrotic syndrome
Atelectasis/Trapped Lung
Asbestosis
Rheumatoid lung
Yellow Nail Syndrome
Duropleural fistula
SVC obstruction
Sarcoidosis
Esophageal perforation
Lupus pleuritis
Constrictive pericarditis
Post-cardiac surgery syndrome

7. Rule of Thumb – Treat underlying disease
CHF
Hepatic Hydrothorax PD
Pancreatitis
Lung/Liver abscess
Chylous ascites
Malignancy
Meig’s syndrome (ascites, benign ovarian tumor)
Parapneumonic
Pulmonary embolism TB
Hypoalbuminemia/Nephrotic syndrome
Atelectasis/Trapped Lung
Asbestosis
Rheumatoid lung
Yellow Nail Syndrome
Duropleural fistula
SVC obstruction
Sarcoidosis
Esophageal perforation
Lupus pleuritis
Constrictive pericarditis
Post-cardiac surgery syndrome

8. Thoracentesis – Diagnostic and Therapeutic
From UpToDate…
INDICATIONS — Pleural effusions are usually detected by physical examination and then confirmed radiographically. Most patients who have a pleural effusion should undergo diagnostic thoracentesis to determine the nature of the effusion (ie, transudate, exudate) and to identify potential causes (eg, malignancy, infection).

9. Thoracentesis – Diagnostic and Therapeutic
What to send?

10. Thoracentesis – Diagnostic and Therapeutic
What to send?
Cell count
Cytology
pH/glucose
Amylase
Triglycerides
ADA
Gram and Culture (bacterial, viral, fungal, AFB)

11. Thoracentesis – Diagnostic and Therapeutic
Reexpansion Pulmonary Edema
If more than 1 liter of pleural fluid is removed at a time during a thoracentesis or from a chest tube RPE may result.
RPE may present as asymptomatic radiographic changes or as complete cardiopulmonary collapse. Mortality rate is 20%.

12. Pleural Fluid Diagnostics
Transpleural pressure imbalance (transudate)
Increased capillary permeability (exudate)
Impaired lymphatic drainage (exudate)
Transdiaphragmatic movement of fluid (transudate)
Pleural effusions of extravascular origin (either)

13. Pleural Fluid Diagnostics
Transpleural pressure imbalance (transudate)
Increased capillary permeability (exudate)
Impaired lymphatic drainage (exudate)
Transdiaphragmatic movement of fluid (transudate)
Pleural effusions of extravascular origin (either)
Transudates are caused by:
Increased Starling forces
Increased systemic capillary forces (increased rate of filtration)
Increased systemic venous HTN (not really)
Pulm venous HTN (CHF)
Fistula or increased compartment pressure
Exudates are caused by:
Impaired protein and cell clearance from pleural space
Leaky mesothelium

14. Pleural Fluid Diagnostics
Light’s Criteria: Effusion is likely exudative if at least one of the following exists:
The ratio of pleural fluid protein to serum protein is greater than 0.5
The ratio of pleural fluid LDH and serum LDH is greater than 0.6
Pleural fluid LDH is greater than 0.7 times the normal upper limit for serum
Lights diagnosis approx 20% of transudates as exudates.
Modified Light’s Criteria: Effusion is likely exudative if at least one of the following exists:
The pleural fluid LDH is greater than 0.67 the upper limit of normal serum concentration

15. Pleural Fluid Diagnostics
Exudate Characteristics
Usually > 1000 nucleated cells
>50,000 nucleated cells is indicative of empyema
< 5000 nucleated cells with mononuclear predominance indicated TB
>80% lymphocytes indicative of transplant rejection, lymphoma, post-CABG, sarcoid, TB, fungal infection, yellow nail syndrome
>10% eosinophils indicative of abestosis, carcinoma, churg-strauss, hemothorax, lymphoma, parasites, PE, sarcoid, TB

16. Pleural Fluid Diagnostics