Lecture 22: Pleural Disease

Question 1

Describe lymph drainage to pleura (parietal and visceral)

Answer 1

Parietal lymphatics drain into internal mammary chain anterioraly and internal intercostal chain posteriorarly; Visceral lymphatics drain to hilar and middle mediastinal lymph nodes

Question 2

Which pleura is primarily responsible for pleural fluid formation and absorption? What is a compensatory function of this structure?

Answer 2

Parietal pleura –> Parietal pleural lymphatics can increase fluid absorption capacity many-fold

Question 3

Three ways to get fluid into pleural space

Answer 3

1. High osmotic pressure in capillaries (transudate); 2. High oncotic pressure in pleural area (junk in pleura) OR decreased oncotic pressure in capillaries (transudate); 3. Altered permeability of pleural membranes (exudate)

Question 4

Which layer of pleura contains the lymphatic stomata?

Answer 4

Parietal pleura

Question 5

What is the difference between exudate and transudate?

Answer 5

Exudate = something is in the fluid; transudate = just fluid

Question 6

Physical findings of pleural effusions

Answer 6

Decreased breath sounds and fremitus, dullness to percussion

Question 7

Chest radiographs usually under/over estimate amount of fluid in pleural effusions? What sign do we look for in chest x-ray?

Answer 7

Under –> takes a lot of fluid (~1/2 liter) to blunt the costophrenic angle

Question 8

What position in chest x-ray detects free-flowing effusions?

Answer 8

Lateral decubitus

Question 9

How do we clear pleural effusions? Describe procedure

Answer 9

Thoracentesis: guide via CXR or ultrasound one interspace below loss of fremitus/dullness over the rib

Question 10

What “chemistries” do we perform on pleural fluid? What else?

Answer 10

Protein, LDH, glucose; cell count, pH, gram stain

Question 11

Light’s criteria

Answer 11

Exudate IF (only need one): pleural fluid/serum protein ratio > 0.5; pleural fluid/serum LDH ratio > 0.6; pleural fluid LDH > 2/3 upper limit of normal

Question 12

What is a pleural exudate often the result of?

Answer 12

Inflammation or tissue destruction

Question 13

What kind of things cause transudative effusions? Most common?

Answer 13

Heart failure (most common), renal problems, hypoalbuminemia

Question 14

These two things can cause EITHER a transudative or exudative effusion

Answer 14

Malignancy, pulmonary emoblism

Question 15

Three causes of pleural effusion

Answer 15

1. Increased hydrostatic pressure (CHF); 2. Decreased plasma oncotic pressure (liver/kidney); 3. Movement of transudative abdominal fluid (ascites)

Question 16

Describe hepatic hydrothorax. Tx?

Answer 16

Pressure in abdomen is positive, pleura is negative, fluid moves up if there is a connection, source is ascities; more common on right side; treat ascites

Question 17

Top two causes of exudative effusions?

Answer 17

Infections and malignancy

Question 18

Some other causes of exudative effusions…

Answer 18

Collagen, PE, Dressler’s, asbestos, pancreatitis…

Question 19

Three categories of parapneumonic effusion

Answer 19

Simple (relatively small, doesn’t have to be drained); Complicated (must be drained; Empyema (pus in chest, must be chained)

Question 20

Parapneuomic effusion is exudate or transudate?

Answer 20

Exudate (inflammatory)

Question 21

What can an undrained empyema lead to?

Answer 21

Fibrothorax or even septic shock

Question 22

Very low pH or very high LDH in parapneumonic effusion means what?

Answer 22

You could have a complicated paraneumonic effusion…You should drain it!

Question 23

Describe tuberculous pleuritis. Exudative or transudative? Mechanism?

Answer 23

Subpleural focus of TB ruptures into pleural space 6-12 weeks after primary infection or reactivation of disease; exudative; TB antigen in pleural space causes hypersensitivity reaction

Question 24

If tuberculous pleuritis is not drained, what can happen?

Answer 24

65% will go onto develop active TB

Question 25

Malignant pleural effusion are usually from where?

Answer 25

Tumor implants on pleural surface (tumor emboli to vsiceral pleura extending to parietal pleura), lymphatics obstructed by tumor to prevent reabsorption

Question 26

Prognosis of malignant pleural effusion

Answer 26

Very poor prognosis

Question 27

Presentation of pleural effusion (symptoms, signs, chest x-ray, ultrasound)

Answer 27

Symptoms: dyspnea, pleuritic chest pain, fever; Signs: dull to percussion, decreased breath sounds, pleural fiction rub; X-ray: blunted angles, meniscus, lateral decubitus; Ultrasound: fluid is sonolucent

Question 28

What pleural fluid glucose finding suggests a complicated effusion? What about pH?

Answer 28

Low glucose; low pH

Question 29

Do you always see organisms on gram stain because of a parapneumonia effusion?

Answer 29

Nope!

Question 30

What does loculated mean?

Answer 30

Fluid not obeying gravity, suggests lots of inflammation in pleural space

Question 31

Do you always tap a simple transudative effusion?

Answer 31

If clear-cut presentation of CHF, these effusions do not necessarily need thoracentesis

Question 32

Pleural effusion from cancer: simple/complicated trans/exudate?

Answer 32

Simple exudate

Question 33

Massive effusion, think…Always get maligant cells?

Answer 33

Cancer; nope ~65%

Question 34

Hemothorax definition

Answer 34

Pleural fluid Hct > 50% serum Hct

Question 35

Two entry points for pneumothorax

Answer 35

Parietal (trauma); Viseral (cyst rupture, ventilation complication, necrosis, post-procedural)

Question 36

Symptoms of spontaneous pneumothorax

Answer 36

Often w/ sudden chest pain and dyspnea

Question 37

Who gets spontaneous pneumothorax

Answer 37

Associated w/ tall, thin people

Question 38

Pnemothorax always need drainage or surgery? Tx options

Answer 38

Not always: observation, simple aspiration, thoracostomy (chest) tube

Question 39

Tension pneumothorax is caused by? Tx?

Answer 39

Formation of a valve: air going into chest but not leaving, pushing heart and lungs to other side; stab something into the lung right away (atm pressure better than what’s happening)

Question 40

Describe malignant mesothelioma (presentation, association, prognosis)

Answer 40

Presents with chest pain, cough; 70% associated with asbestos exposure (30+ year latency), poor prognosis