Pleural Disease Flashcards
What is the normal pleural pressure? Why is it negative?
-5 cmH2O
It is negative due to the competing elastic recoils of the chest (outward) and lung (inward)
What determines the filtration coefficient of the pleura? When might it be increased?
“How leaky the pleura are”
May be increased in infection, inflammation, malignancy
What could cause an increase in Pulmonary capillary hydrostatic pressure leading to effusion?
LV failure
What could cause a decrease in pulmonary capillary oncotic pressure leading to effusion?
Cirrhosis
Malnutrition
Hypoalbuminemia
Nephrotic syndrome
What could cause a decrease in the pleural hydrostatic pressure leading to effusion?
Atelectasis
What are some physical exam findings of pleural effusion?
Dullness to percussion
Decreased breath sounds
Tactile fremitus
Egophony (e -> a change)
How might a pleural effusion be visualized on a CXR?
Blunting of the costophrenic angle
Meniscus sign
White out
Lateral decubitus position shows laying of fluid
What is a loculation? How is it treated?
Inflammatory pleural effusion due to infection that is well circumscribed because the area around it has fused and locked it in place.
Loculations require surgical intervention
How can you determine the difference between a pleural effusion and atelectasis on CXR?
You may see complete white out in both.
Look at the mediastinum. The mediastinum would shift towards atelectasis, but away from a pleural effusion
Where is the needle inserted in a thoracentesis?
OVER the rib (avoid the neurovascular bundle)
What are Light’s Criteria for determining if an effusion is exudate?
What is the one new “revised” criteria?
TPpl/TPserum greater than 0.5
LDHpl/LDHserum greater than 0.6
LDH greater than 200
Cholesterol(pl) greater than 45
What are the most common causes of transudative effusions?
Heart failure
Kidney failure
Liver failure
Atelectasis
What is an empyema? How is it different from a parapneumonic effusion?
Empyema - Infection in the pleural space
In a parapneumonic effusion, the infection is in the lung itself, which cause a pleural effusion. The pleura are not infection in a parapneumonic effusion
What can be determined by the pH of the pleural fluid?
Low pH may be seen with infection (empyema), malignancy, and esophageal rupture
How do you determine a hemothorax?
Blood in the pleural space
Pleural fluid hematocrit would need to be 0.5 or greater than peripheral hematocrit
Describe characteristics of a TB effusion
Exudative Lymphocytic Less than 5% mesothelial cells Positive ADA TB skin test may be negative early on
Describe characteristics of a Malignant Effusion
Exudative Lymphocytic RBCs present May have low pH and glucose Large effusion with tendency to reaccumulate
Describe characteristics of a Pulmonary embolism-related effusion
Small
Unilateral
Exudative
May be bloody
Describe characteristics of an Esophageal Rupture effusion
Left sided
Low pH
High amylase
Describe characteristics of an Endometriosis-related effusion
Bloody
May have hemoptysis
Describe characteristics of a “Hepatic” effusion
Underlying cirrhosis
Transudates
R more common the L
Rapidly reaccumulates
How could an empyema be definitively diagnosed?
Milky white effusion with
Positive Gram stain
Positive culture
Pus
How is a chylothorax distinguished from a pseudochylothorax?
Both are milky white effusions
Chylothorax (TG over 110)- due to malignancy, trauma, mediastinal disease
Pseudochylothorax (TG over 100 and Chol over 200)- due to chronic inflammation
Describe the basic mechanism of a pneumothorax
Either the alveoli get punctured or there is a hole in the chest wall, resulting in air rushing into pleural space.
Lungs collapse inward
Chest wall bulges out
How can a pneumothorax be at risk for tension?
How does tension pneumothorax kill you?
Ball valve mechanism
Breathe in, hole in chest wall closes, more air trapped inside the pleural space.
High intrathoracic pressure impedes venous return. No blood returns to the heart and you go into shock and die
Pneumothorax
Symptoms
May be asymptomatic Chest pain Discomfort Dyspnea Cough Shock (if tension)
Pneumothorax
Physical Exam findings
Unilateral hyperinflation
Decreased breath sounds and tactile fremitus
Hyperresonance
Pneumothorax
CXR Findings
Hyperlucent lung fields
Lack of lung markings
Shift of mediastinum if tension
Pneumothorax (asymptomatic)
Treatment
Observation
Give them 100% O2
Pneumothorax (symptomatic)
Treatment
Drain the pneumothorax with a chest tube
