Flashcards in Pleural Diseases Deck (31):
What's the blood supply to the parietal pleura?
What's the blood supply to the visceral pleura?
Pulmonary and a small amount of bronchial circulation.
What drives a small net movement of fluid into the pleural space under normal conditions)?
Does the parietal and visceral pleura equally contribute?
Parietal pleura has both higher hydrostatic and higher oncotic pressure than the pleura space, but the hydostatic pressure is high enough to cause some net fluid movement.
There is no net fluid movement across the visceral pleura. (under normal conditions)
How does fluid in the pleura space get reabsorbed?
What about of excess fluid production can they handle?
Stomata on the parietal pleaura - they're concentrated inferiorly and directly connect with lymphatics.
Can reabsorb up to 28x normal production.
What are the symptoms of pleura effusion?
Shortness of breath.
Vague chest pressure or discomfort.
Pleuritic chest pain.
Signs and symptoms of underlying disease disease.
How do palpation physical exam findings change in pleural effusion?
Decrease in chest wall excursion.
Decrease in tactile fremitus.
How do percussion exam findings change in pleural effusion?
Dull to percussion.
How do auscultation exam findings change in pleural effusion?
Diminished or absent breath sounds.
Most straightforward imaging to confirm a pleural effusion?
Chest x-ray - blunting of costodiaphragmatic angle.
(or shifting of mediastinal structures if massive)
But you can see it on CT, ultrasound.
When should and effusion be tapped?
Thoracentesis should be done anytime there's > 10 mm fluid (on ultrasound or lateral dicubitus CXR).
Effusion color is useful.
Yeah.... in a fairly obvious way. But "straw-colored" fluid doesn't tell you much.
What's the difference between transudate and exudate?
Transudate: from hydrostatic/oncotic pressure imbalance.
Exudate: from increased capillary permeability.
How do Light's criteria help you tell exudate vs. transudate?
If 1 or more of the following criteria are met, it's exudate:
Pleural fluid:serum protein > 0.5.
Pleural fluid:serum LDH > 0.6.
Pleural fluid LDH > 2/3 upper limit of normal for serum.
Basically, if the fluid resembles serum in protein and LDH levels, it's exudate.
3 ways to get increased hydrostatic pressure -> transudate?
3 ways to get decreases in oncotic pressure -> transudate?
(all have not enough protein in serum)
Why is there pleural effusion in SVC syndrome?
Recall that the parietal pleura is drained by the systemic circulation -> if the systemic circulation backs up... increased hydrostatic in parietal pleura -> effusion.
2 most common types of cause of exudative effusions?
Infections and malignancy.
(though PE, connective tissue disease, some drugs, and lots of other things can cause it)
Why would there be decreased glucose in the fluid?
How about low pH?
Highly metabolically active things, including infection, malignancy, rheumatoid arthritis, and esophageal rupture.
3 types of cells that can be predominant when there's increased cellularity of the effusion?
PMNs - infection.
Lymphocytes - Cancer, TB, chylothorax(?)
Eosinophils - trauma, PTX, asbestos, drug reaction, parasitic infecition.
Treatment for pleural effusion?
Depends on the underlying cause...
3 classifications of exudative effusions?
Parapneumonic - not severe, doesn't need therapy.
Complicated parapneumonic effusion (CPE).
What distinguishes empyema and CPE from parapneumonic exudate?
Abnormal chemistries - low pH, low glucose, high PMNs.
What distinguishes empyema from CPE?
Chemistries are the same, but empyema has frank pus and bacteria in the effusion.
Treatment of CPE or empyema? (2 things)
Drainage with chest tube / surgery.
Larger effusions are more likely to be malignant.
okay. And it's a bad prognostic sign.
Treatment for malignant pleural effusion? (3 things)
Treat underlying cancer.
It's a palliative treatment for a malignant effusion - drain fluid, spray in talcum powder... makes pleura stick together, reducing recurrent effusion.
Autoimmune diseases that can cause pleural effusions?
(Effusions of SLE tend to be more painful.)
Causes of pneumothorax (PTX)?
Interstitial Lung Disease (ILD)
Iatrogenic (procedures, mechanical ventilation)
3 kinds of ILD that can lead to PTX?
Lymphangioleiomyomatosis (LAM) -recurrent PTX in a young female.
Langerhans cell histiocytosis.