Pleural Disease Flashcards
Amount of pleural fluid in the pleural space normally
0.3 ml/kg
Location of lymphatics that drain the pleural space
Parietal pleura
Pleural filtration based on location of lung
Filtration decreases from apex to base
Flow of pleural fluid
Costal to mediastinal region along diaphragm and mediastinal surfaces
Pleural pressure at FRC
-3 to -5 cmH2O
Effects of air, time, and lidocaine on pleural fluid pH
Air and time in syringe will increase pH
Lidocaine will decrease pH
pleural fluid pH that is predictive of poor outcomes and failed pleurodesis in malignancy
< 7.30
Light’s criteria
Pleural/serum ratios
Protein > 0.5
LDH > 0.6
LDH > 2/3 upper limit of serum LDH
Any 1 positive means exudate
Reason for falsely classifying a transudate as an exudate via light’s criteria
Diuretic use (25% of cases)
Pleural fluid cholesterol threshold for exudate classification
> 55 mg/dl
Pleural protein gradient for classification of transudate or exudate
Serum to pleural gradient
> 3.1 is transudate
< 3.1 is exudate
Serum to pleural albumin gradient predictive of transudate
> 1.2 gm/dl
Serum or pleural NT pro BNP suggestive of transudate
> 1300 pg/ml
6 causes of common transudative effusions
- Congestive heart failure
- Hepatic hydrothorax
- Nephrotic syndrome
- Urinothorax
- Peritoneal dialysis
- Trapped lung
9 common causes of exudative effusions
- Benign asbestos effusion
- Chylothorax
- GI Disease
- Neoplastic
- Parapneumonic effusion
- PE after CABG
- TB
- Systemic diseases
- Vascular effusions
Percentage of hepatic hydrothorax where there is no ascites found
20%
Criteria for spontaneous infection of hepatic hydrothorax
- Pleural fluid neutrophils > 250 and a positive culture
OR
- Pleural fluid neutrophils > 500 with negative culture