Pleural and Mediastinal Disease DSA

Question 1

What is a pleural effusion?

Answer 1

Created by an imbalance between production and removal of fluid from the pleural space.

Question 2

What are the 2 mechanisms that leads to accumulation of fluid in the pleural space?

Answer 2

1. Increased capillary hydrostatic pressure

2. Decreased plasma oncotic pressure

Question 3

What mechanisms cause pleural effusion by increasing hydrostatic pressure?

Answer 3

1. HF
2. SVC syndrome
3. Constrictive pericarditis

Question 4

What is the most common finding auscultated over a pleural effusion; and what is auscultated toward the top of an effusion?

Answer 4

• Decreased to absent breath sounds over an effusion
• Bronchial breath sounds toward the top of an effusion

Question 5

What mechanisms cause pleural effusion by decreasing plasma oncotic pressure?

Answer 5

• Cirrhosis
• Nephrotic syndrome
• Hypoalbunemia

Question 6

What are the 3 leading causes of pleural effusion in the US?

Answer 6

• 1. Heart failure
• 2. Pneumonia
• 3. Cancer

Question 7

Which imaging study is usually the first study used to identify and quantify the amount of fluid seen with a pleural effusion?

Answer 7

CXR

Question 8

How much pleural fluid is needed to blunt the costophrenic angle on CXR?

Answer 8

~250 mL

Question 9

Which sign is created as greater amounts of fluid with a pleural effusion opacify the lower thorax?

Answer 9

“Meniscus sign”

Question 10

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?

Answer 10

Decubitus films

Question 11

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?

Answer 11

1-cm distance

Question 12

Bilateral transudative pleural effusions are commonly associated with what underlying diseases?

Answer 12

HF, cirrhosis, nephrosis, liver failyre

Question 13

Bilatral exudative pleural effusions suggest what underlying disease(s)?

Answer 13

Malignancy, but may aso occur in pt’s w/ pleuritis due to SLE and other collagen vascular disorders

Question 14

Lymphocytic dominant exudate is most often due to

Answer 14

• Maligancy
• TB

Question 15

How do we distinguish between transudative and exudative?

Answer 15

Compare pleural fluid and serum levels of LDH and protein

Question 16

Exudative pleural effusions are predominately caused by what?

Answer 16

• MC: Inflammation, infections, malignancies
• Less commonly by: collagen vascular disease, intra-abdominal process and hypothyroidism
• Venous thromboembolic disease

Question 17

Transdative pleural effusions are predominately caused by what?

Answer 17

Unbalanced hydrostatic forces and are associated with:

• HF,
• Cirrhosis
• Nephrophtic syndrome
• Pericarditis

Question 18

_________ effusions typically have low leukocyte count (below 1000/uL).

Answer 18

Transudative

Question 19

• Process to treat pleural effusion via thoracentesis

Answer 19

• 1. CXR: ID and quantify fluid in pleural effusion: 250 mL of pleural fluid is needed to blunt the costophrenic angle on CXR.
     * +: Meniscus sign
• 2. 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.

Question 20

What proteins/LDH levels would indicate a transudative effusion?

Answer 20

Transudative effusion:

• pleura/serum levels of:
  
  • proteins: < .5
  • LDH: < .6
  • pleural fluid LDH is _____ upper limit of NL for serum: <2/3

Question 21

If a exudate effusion is lymphocytic, what should we test for and via what tests?

Answer 21

TB

• - Adenosine deaminase activity
• - PCR

Question 22

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?

Answer 22

• 1. No more than 1.5 L to minimize liklihood of re-expansion
• 2. 2L or more can be safely removed.

Question 23

How do we treat a pleural effusion assx with pneumonia?

Answer 23

drain fluid with catheter or chest tube

Question 24

Air in the pleural space is calleda _______

Answer 24

pneumothorax

Question 25

How do we classify **pneumothorax**?

Answer 25

* **Spontaneous** (primary or secondary) * **Traumatic**

Question 26

* What is the difference between a **primary spontaneous** and **secondary sponateous pneumothorax?** * **Traumatic**? * **Iatrogenic pneumothorax**?

Answer 26

**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,

Question 27

**Tension pneumothorax** occurs in what situations? Pressure of air in pleural space ____ ambient pressure throughout respiratory cycle

Answer 27

* 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.

Question 28

**Primary pneumothroax** affects mainly whom?

Answer 28

Tall, thin boys M between 10-30

Question 29

How is **primary pneumothorax** though to occur?

Answer 29

**High (-) intrapleural pressure** causes subpleural blebs to rupture.

Question 30

**Secondary pneumothorax** is a complication of what?

Answer 30

1. **COPD** 2. **Asthma** 3. **CF** 4. **TB** 5. **Pneumocystitis pneumonia** 6. **Menstruation** 7. Interstitial lung diseases: sarcoidosis. LCH and tuberous sclerosis

Question 31

What are **risk factors** for the development of a Pneumothorax?

Answer 31

1. **Aerosolized pentamidine** 2. **Prior hx of pneumocystitis pneumonia**

Question 32

50% of patients with pneumothorax in the setting of **recurrent** (but not primary) **Pneumocystis pneumonia** will develop what?

Answer 32

Pneumothorax on the **contralateral side**

Question 33

What are the symptoms and signs of **pneumothorax**?

Answer 33

1. **Chest pain,** ranging from minimal - severe on affected side 2. **Dyspnea** that **begin at rest** and **resolve within 24 hours,** even if pneumothorax persists.

Question 34

How does a **small pneumothorax** present differently than a **large pneumothorax**?

Answer 34

* **Small pneumothorax:** PE is NL; maybe mild tachycardia * **Large pneumothorax:** decreased breath sounds, tactile fremitis, chest movement

Question 35

**Tension pneumothorax** should be suspected in the presence of what signs/sx's?

Answer 35

* - Marked **tachycardia** * - **HYPO**tension * - **Mediastinal or trachealshift**

Question 36

Demonstration of what on a **CXR** is diagnostic of a **pneumothorax**?

Answer 36

**_Visceral_ pleural line**

Question 37

Which characteristic sign may be seen on chest radiograph in **supine pt's** presenting with pneumothorax?

Answer 37

**"Deep sulcus" sign**

Question 38

* The diagnosis of **primary pneumothorax** is obvious in ______________ and can be confirmed on CXR. * What about a **secondary pneumothorax**?

Answer 38

* Young, tall, think cig smoking man * Hard to tell apart a emphysematous bleb vs loculated pneumothorax

Question 39

**Pneumothorax** can mimic what?

Answer 39

* **1. MI** * **2. PE** * **3. Pneumonia**

Question 40

What is treatment for reliable pt with a small (\<15% of a hemithorax), s**table, spontaneous primary pneumothorax?**

Answer 40

Observation

Question 41

What are indications ofr a **chest tube placement (**tube thoracostomy)?

Answer 41

* **1. Secondary pneumothorax** * **2. Large pneumothrox** * **3. Tension pneumothorax** * **4. Those who have pneumothorax while on mechanical ventiliation**

Question 42

What 3 major structures are found in the **posterior** mediastinal compartment?

Answer 42

* **1. Descending thoracic aorta** * **2. Esophagus** * **3. Thoracic duct** * **4. Azygous/hemiazygous vein**

Question 43

What is the **mediatinum**?

Answer 43

**Area between the pleural sacs**

Question 44

Where does the **anterior mediastinum** lie? ## Footnote **Middle mediastinum?** **Posterior mediastium?**

Answer 44

* **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.

Question 45

What is located in the **middle mediastinum**?

Answer 45

1. Heart 2. Ascending and transverse arch of the aorta 3. Vena cava 4. Brachiocephalic arteries 5. Phrenic nerves 6. Trachea 7. Bronchi and assx LN 8. Pulmonary a. and vs.

Question 46

What are the 3 most common masses of the **middle mediastinum** (remembered VAC)?

Answer 46

- **Vascular masses** - **Adenopathy** (LN enlargement) from metastases or granulomatous disease - **Cysts** (pleuropericardial and bronchogenic)

Question 47

Most causes of **acute mediastinitis** are what?

Answer 47

* 1. **Esophageal perforation** (Boerhaave syndrome) * 2. **Median sternotomy** for cardiac surgery

Question 48

Most patients with **esophageal rupture** are present how? What about with mediastinitis after **median sternotomy**?

Answer 48

1. -Acutely ill with **CP** and **SOB** due to infection 2. - **Wound drainage**

Question 49

Spectrum of **chronic mediatintis** ranges from ______ to \_\_\_\_

Answer 49

**Granulomatous inflammation of LN** =\> **fibrosing mediastinits**