Pleural Disorders (Harrisons 263) Flashcards
Transudative pleural effusion occurs when…
…SYSTEMIC factors influencing pleural fluid are altered.
Exudative pleural effusion occurs when…
…LOCAL factors influencing pleural fluid are altered.
Most common cause of pleural effusion
Left ventricular failure
Why does left ventricular failure cause pleural effusion?
Increased amounts of fluid in the interstitial spaces of lungs exit across the visceral pleura, overwhelming the lymphatic system’s capacity to remove fluid
How can we determine that a pleural effusion is secondary to heart failure?
A pleural fluid BNP of > 1500 is “virtually diagnostic”
Hepatic hydrothorax
Direct movement of peritoneal fluid through small openings in the diaphragm into the pleural space
Parapneumonic effusions
Associated with bacterial pneumonia, lung abscess, or bronchiectasis
Most common cause of EXUDATIVE pleural effusion in the US
If the fluid in a parapneumonic effusion separates the lung from chest wall by > 10mm…
…a therapeutic thoracentesis should be performed
Factors that indicate the need for a procedure more invasive than thoracentesis, in order of increasing importance:
1) Loculated pleural fluid
2) Pleural fluid pH < 7.2
3) Pleural fluid glucose < 60 mg/dL
4) Positive Gram stain or culture of pleural fluid
5) Presence of gross pus in the pleural space
How is a malignant effusion diagnosed?
Cytology of the pleural fluid
Mesotheliomas are…
primary tumors of the mesothelial cells that line the pleural cavities.
What’s the most common factor in mesothelioma?
Asbestos exposure
The most commonly overlooked diagnosis of a patient with a pleural effusion:
pulmonary embolism
Jeopardy!
A very common cause of pleural effusion in many parts of the world, but relatively uncommon in the US.
What is tuberculosis?
How do we diagnose a tuberculous pleuritis?
high levels of TB markers in the pleural fluid
Pleural effusions can be caused by viral infection. Why is it important to know this?
They tend to resolve spontaneously with no long-term effects, and one should not try too aggressively to diagnose an undiagnosed effusion if the patient is improving clinically.
How do we diagnose hemothorax?
If the pleural fluid obtained from thoracentesis has a hematocrit more than half of that in the peripheral blood
What usually causes hemothorax?
That would be trauma!
But ruptured blood vessel or tumor can do it too.
What’s a pneumothorax?
presence of gas in the pleural space
What’s a spontaneous pneumothorax?
One that occurs without trauma
Jeopardy!
A spontaneous pneumothorax that happens in the absence of lung disease
What is a primary spontaneous pneumothorax, Alex?
Jeopardy again!
A spontaneous pneumothorax that happens in the presence of lung disease.
What is a secondary pneumothorax?
Spontaneous secondary pneumothorax can happen with any lung disease, but mostly they stem from…
COPD!
True or False: Traumatic pneumothorax results from penetrating trauma only.
False! It can result from non-penetrating trauma as well.
How is simultaneous hemopneumothorax treated?
One chest tube in the upper chest (evacuating air) and one in the lower chest (draining blood).
What are the most common causes of iatrogenic pneumothorax?
1) transthoracic needle aspiration
2) thoracentesis
3) insertion of CVL
Tension pneumothorax: not a big deal right?
WRONG! It is a medical emergency & it’s probably gonna kill yer patient if you don’t fix it!
Why does tension pneumothorax kill people?
Increased pressure in the thorax is also increased pressure in the mediastinum, which reduces cardiac output. Oh no!
When does tension pneumothorax usually happen?
During mechanical ventilation or resuscitation. (Oops. Our bad.)
Signs of tension pneumothorax:
1) Difficulty in ventilation or high peak inspiratory pressures
2) large hemithorax with no breath sounds
3) Hyperresonance to percussion
4) shift of mediastinum away from the tension pneumo
How do we fix a tension pneumo?
Large bore needle inserted into the pleural space through 2nd intercostal space. If a lot of air escapes, time to place a chest tube!
