Pleural and Mediastinal Disease DSA Flashcards
What is a pleural effusion?
Created by an imbalance between production and removal of fluid from the pleural space.
What are the 2 mechanisms that leads to accumulation of fluid in the pleural space?
1. Increased capillary hydrostatic pressure
2. Decreased plasma oncotic pressure
What mechanisms cause pleural effusion by increasing hydrostatic pressure?
- HF
- SVC syndrome
- Constrictive pericarditis
What is the most common finding auscultated over a pleural effusion; and what is auscultated toward the top of an effusion?
- Decreased to absent breath sounds over an effusion
- Bronchial breath sounds toward the top of an effusion
What mechanisms cause pleural effusion by decreasing plasma oncotic pressure?
- Cirrhosis
- Nephrotic syndrome
- Hypoalbunemia
What are the 3 leading causes of pleural effusion in the US?
- 1. Heart failure
- 2. Pneumonia
- 3. Cancer
Which imaging study is usually the first study used to identify and quantify the amount of fluid seen with a pleural effusion?
CXR
How much pleural fluid is needed to blunt the costophrenic angle on CXR?
~250 mL
Which sign is created as greater amounts of fluid with a pleural effusion opacify the lower thorax?
“Meniscus sign”
After the presence of a pleural effusion is documented what study is used to evaluate whether an effusion is free-flowing or loculated (non-free flowing) and whether a sufficient quantity is present to perform thoracentesis?
Decubitus films
How much distance measured from the pleural fluid line to the chest wall on a decubitus radiograph is indicative of adequate pleural fluid to perform thoracentesis?
1-cm distance
Bilateral transudative pleural effusions are commonly associated with what underlying diseases?
HF, cirrhosis, nephrosis, liver failyre
Bilatral exudative pleural effusions suggest what underlying disease(s)?
Malignancy, but may aso occur in pt’s w/ pleuritis due to SLE and other collagen vascular disorders
Lymphocytic dominant exudate is most often due to
- Maligancy
- TB
How do we distinguish between transudative and exudative?
Compare pleural fluid and serum levels of LDH and protein
Exudative pleural effusions are predominately caused by what?
- MC: Inflammation, infections, malignancies
- Less commonly by: collagen vascular disease, intra-abdominal process and hypothyroidism
- Venous thromboembolic disease
Transdative pleural effusions are predominately caused by what?
Unbalanced hydrostatic forces and are associated with:
- HF,
- Cirrhosis
- Nephrophtic syndrome
- Pericarditis
_________ effusions typically have low leukocyte count (below 1000/uL).
Transudative
- Process to treat pleural effusion via thoracentesis
-
CXR: ID and quantify fluid in pleural effusion: 250 mL of pleural fluid is needed to blunt the costophrenic angle on CXR.
* +: Meniscus sign
-
CXR: ID and quantify fluid in pleural effusion: 250 mL of pleural fluid is needed to blunt the costophrenic angle on CXR.
- Find out whether the fluid is free-flowing or loculated (not free flowing) and whether there is enough fluid to perform a thoracentesis: Decubitis film and 1 cm distance between [pleural fluid line - chest wall] => thoracentis
* - Spiral chest CT to test for PE
* - US to help guide thoracentesis, detect loculations or detect pleural abnormalities not detected by CXR.
- Find out whether the fluid is free-flowing or loculated (not free flowing) and whether there is enough fluid to perform a thoracentesis: Decubitis film and 1 cm distance between [pleural fluid line - chest wall] => thoracentis
What proteins/LDH levels would indicate a transudative effusion?
Transudative effusion:
- pleura/serum levels of:
- proteins: < .5
- LDH: < .6
- pleural fluid LDH is _____ upper limit of NL for serum: <2/3
If a exudate effusion is lymphocytic, what should we test for and via what tests?
TB
- - Adenosine deaminase activity
- - PCR
Therapeutic thoracentesis should be limited to the removal of how much fluid at a time?
What about a massive pleural effusion with a mediastinal shift?
- No more than 1.5 L to minimize liklihood of re-expansion
- 2L or more can be safely removed.
How do we treat a pleural effusion assx with pneumonia?
drain fluid with catheter or chest tube
Air in the pleural space is calleda _______
pneumothorax
How do we classify pneumothorax?
- Spontaneous (primary or secondary)
- Traumatic
- What is the difference between a primary spontaneous and secondary sponateous pneumothorax?
- Traumatic?
- Iatrogenic pneumothorax?
Primary spontaneous pneumothorax: occurs w/o lung disease
Secondary spontaneous pneumothorax: d/t a underlying pulmonary disease
Traumatic: penetrating or blunt trauma
Iatrogenic pneumothorax: occurs after a thoracentesis, pleural biopsy, catheter placement,
Tension pneumothorax occurs in what situations?
Pressure of air in pleural space ____ ambient pressure throughout respiratory cycle
- Penetrating trauma, lung infection, CP resuscitation, positive -pressure mechanical ventilation.
- Pressure of air in pleural space > ambient pressure t/o resp cycle; air enters pleural space on inspiration but does not leave on exhalation.
Primary pneumothroax affects mainly whom?
Tall, thin boys
M between 10-30
How is primary pneumothorax though to occur?
High (-) intrapleural pressure causes subpleural blebs to rupture.
Secondary pneumothorax is a complication of what?
- COPD
- Asthma
- CF
- TB
- Pneumocystitis pneumonia
- Menstruation
- Interstitial lung diseases: sarcoidosis. LCH and tuberous sclerosis
What are risk factors for the development of a Pneumothorax?
- Aerosolized pentamidine
- Prior hx of pneumocystitis pneumonia
50% of patients with pneumothorax in the setting of recurrent (but not primary) Pneumocystis pneumonia will develop what?
Pneumothorax on the contralateral side
What are the symptoms and signs of pneumothorax?
- Chest pain, ranging from minimal - severe on affected side
- Dyspnea
that begin at rest and resolve within 24 hours, even if pneumothorax persists.
How does a small pneumothorax present differently than a large pneumothorax?
- Small pneumothorax: PE is NL; maybe mild tachycardia
- Large pneumothorax: decreased breath sounds, tactile fremitis, chest movement
Tension pneumothorax should be suspected in the presence of what signs/sx’s?
- Marked tachycardia
- HYPOtension
- Mediastinal or trachealshift
Demonstration of what on a CXR is diagnostic of a pneumothorax?
Visceral pleural line
Which characteristic sign may be seen on chest radiograph in supine pt’s presenting with pneumothorax?
“Deep sulcus” sign
- The diagnosis of primary pneumothorax is obvious in ______________ and can be confirmed on CXR.
- What about a secondary pneumothorax?
- Young, tall, think cig smoking man
- Hard to tell apart a emphysematous bleb vs loculated pneumothorax
Pneumothorax can mimic what?
- 1. MI
- 2. PE
- 3. Pneumonia
What is treatment for reliable pt with a small (<15% of a hemithorax), stable, spontaneous primary pneumothorax?
Observation
What are indications ofr a chest tube placement (tube thoracostomy)?
- 1. Secondary pneumothorax
- 2. Large pneumothrox
- 3. Tension pneumothorax
- 4. Those who have pneumothorax while on mechanical ventiliation
What 3 major structures are found in the posterior mediastinal compartment?
- 1. Descending thoracic aorta
- 2. Esophagus
- 3. Thoracic duct
- 4. Azygous/hemiazygous vein
What is the mediatinum?
Area between the pleural sacs
Where does the anterior mediastinum lie?
Middle mediastinum?
Posterior mediastium?
- Anterior mediastinum is located from sternum => pericardium/brachiocephalic vessels posteriorly.
- Middle mediastium is located from anterior to posterior mediastium.
- Posterior mediastinum is located from pericardium/trachea => vertebral column.
What is located in the middle mediastinum?
- Heart
- Ascending and transverse arch of the aorta
- Vena cava
- Brachiocephalic arteries
- Phrenic nerves
- Trachea
- Bronchi and assx LN
- Pulmonary a. and vs.
What are the 3 most common masses of the middle mediastinum (remembered VAC)?
- Vascular masses
- Adenopathy (LN enlargement) from metastases or granulomatous disease
- Cysts (pleuropericardial and bronchogenic)
Most causes of acute mediastinitis are what?
- Esophageal perforation (Boerhaave syndrome)
- Median sternotomy for cardiac surgery
Most patients with esophageal rupture are present how?
What about with mediastinitis after median sternotomy?
- -Acutely ill with CP and SOB due to infection
- Wound drainage
Spectrum of chronic mediatintis ranges from ______ to ____
Granulomatous inflammation of LN => fibrosing mediastinits