Pleural Effusions and Thoracocentesis

Question 1

Pleural Effusions

Fluid accumulates in the pleural space by three mechanisms? 3

Answer 1

• increased drainage of fluid into the space
• increased production of fluid by cells in the space
• decreased drainage of fluid from the space

Question 2

What is considered Intrapulmonary pressure?

1. The pressure where?
2. How does this pressure change as the chest expands?
3. Which causes what?

Answer 2

1. the pressure within the alveoli
2. as the chest expands on inspiration the intrapulmonary pressure becomes more negative,
3. which causes air to be sucked into the lungs.

Question 3

1. What is considered Intrapleural pressure?

2. negative pressure may be lost if fluid collects where?

Answer 3

Intrapleural pressure
1. Negative pressure is created in the pleural space as the thoracic cage enlarges and the lungs recoil during normal inspiration

2. in the pleural space, making the lung unable to expand fully.

Question 4

1. Up to how much of pleural fluid is normally present in the pleural space, an amount not detectable on conventional chest radiographs?
2. Pleural effusion is what?

Answer 4

1. 25 ml

2. an abnormal accumulation of fluid in the pleural space.

Question 5

Main causes of a Pleural Effusion

6

Answer 5

1. Congestive Heart Failure (CHF)
2. Liver failure
3. Infection
4. Atelectasis
5. Cancer
6. Trauma

Question 6

1. What is a hemothorax?
2. usually results from?
3. What usually leaks blood into the pleural space?
4. Can occur as a result of what? 4

Answer 6

1. Blood
2. Usually results from chest injury
3. A blood vessel ruptures into the pleural space or a bulging area into the aorta (aortic aneurysm) leaks blood into the pleural space
4. Can occur as a result of
   - bleeding from the ribs,
   - chest wall,
   - pleura
   - the lung

Question 7

Pleural fluid types

5

Answer 7

1. Transudate
2. Exudate
3. Empyema
4. Chyle
5. Hemothorax

Question 8

IMAGING
1. About ______ of pleural fluid must be present before effusion can be detected on conventional posteroanterior chest x- ray.

2. What position on the affected side will almost always confirm fluid?
3. Pleural fluid may become trapped (“loculated”) by pleural adhesions, forming unusual collections along the chest wall or in the lung fissures. What is useful to locate loculated or small effusions?
4. Massive pleural effusion (opacification of an entire hemithorax) is usually caused by what? 2
5. What is useful in free or loculated pleural fluid?

Answer 8

1. 250 mL
2. Lateral decubitus
3. Ultrasound or CT
4. • cancer but has been
   • observed in tuberculosis and other diseases.
5. CT scanning

Question 9

TECHNIQUE of THORACENTESIS

What position?

Answer 9

sitting position

Question 10

TECHNIQUE of THORACENTESIS
(Insertion site)
Determination: Localization of the pleural fluid? 4

Answer 10

1. Physical examination
2. PA and lateral radiography
3. Ultrasound
4. CT

Question 11

TECHNIQUE of THORACENTESIS

1. Insertion site?
2. Preferably where? 2

Answer 11

1. The upper end of the effusion of under the superior edge of the inferior rib
2. • Preferably 5-6th intercostal space
   • 2 cm below tip of scapula

Question 12

TECHNIQUE of THORACENTESIS
(Procedure)
7

Answer 12

1. Sterilization of the insertion site
2. Anesthesia to the skin, costal periost and pleura
3. Removal of the fluid with 25-50 heparinized syringe
4. Follow-up radiography
5. Plastic or tephlon catheter, 3-way stopcock
6. 350-1000-1500 ml removal of the fluid at once
7. Ending when pleural pressure