316 Disorders of the Pleura

Question 1

From where does the effusion enter and leave?

Answer 1

fluid enters the pleural space from the capillaries in the parietal pleura and is removed via the lymphatics in the parietal pleura. Fluid also can enter the pleural space
from the interstitial spaces of the lung via the visceral pleura or from the peritoneal cavity via small holes in the diaphragm.

Question 2

The lymphatics have the capacity to absorb how many times more fluid than is formed normally?

Answer 2

20 times

Question 3

First step to determine the cause of pleural effusion?

Answer 3

The first step is to determine whether the effusion is a transudate or an exudate.

Question 4

Causatives factors for transudative pleural effusion.

Answer 4

A transudative pleural effusion occurs when systemic factors that influence the formation and absorption of pleural fluid are altered.

Question 5

Causative factors for exudative pleural effusion.

Answer 5

exudative pleural effusion occurs when local factors that

influence the formation and absorption of pleural fluid are altered.

Question 6

leading causes of transudative pleural effusions?

Answer 6

leading causes of transudative pleural effusions in the United States are left ventricular failure and cirrhosis.

Question 7

leading causes of exudative pleural effusions?

Answer 7

leading causes of exudative pleural effusions are bacterial pneumonia, malignancy, viral infection, and pulmonary embolism.

Question 8

Criteria for exudative pleural effusions?

,

Answer 8

1. Pleural fluid protein/serum protein >0.5
2. Pleural fluid LDH/serum LDH >0.6
3. Pleural fluid LDH more than two-thirds the normal upper limit for serum

Question 9

Light misidentify which % of transudates as exudates.

Answer 9

25%

Question 10

Gradient of protein levels in the serum and the pleural fluid in which the exudative categorization by these criteria can be ignored.

Answer 10

If this gradient is more than 31 g/L (3.1 g/dL), the exudative categorization by these criteria can be ignored because almost all such patients have a transudative pleural effusion.

Question 11

What is the most common cause of pleural effusion?

Answer 11

The most common cause of pleural effusion is left ventricular failure.

Question 12

Causes of pleural effusion with less than 60 mg/dL of glicose?

Answer 12

Malignancy
Bacterial infections
Rheumatoid
pleuritis

Question 13

When should a diagnostic thoracentesis be performed in heart failure?

Answer 13

a diagnostic thoracentesis should be performed if the effusions are not bilateral and comparable in size, if the patient is febrile, or if the patient has pleuritic chest pain to verify that the patient has a transudative effusion. If the effusion persists despite therapy, a diagnostic thoracentesis should be performed.

Question 14

N-terminal pro-brain natriuretic peptide (NT-proBNP) value diagnostic of congestive heart failure?

Answer 14

more than 1500 pg/mL

Question 15

% of patients with cirrhosis and pleural effusions?

Answer 15

Pleural effusions occur in ~5% of patients with

cirrhosis and ascites.

Question 16

Parapneumonic effusions occur in which diseases?

Answer 16

Parapneumonic effusions are associated with bacterial pneumonia, lung abscess, or bronchiectasis.

Question 17

What is an empyema?

Answer 17

Empyema refers to a grossly purulent effusion.

Question 18

Presentation of a patient with anaerobic infection?

Answer 18

Patients with anaerobic infections present with a subacute illness with weight loss, a brisk leukocytosis, mild anemia, and a history of some factor that predisposes them to aspiration.

Question 19

When should you perform a therapeutic thoracentesis?

Answer 19

If the free fluid separates the lung from the chest wall by

>10 mm, a therapeutic thoracentesis should be performed.

Question 20

What are the factors indicating the likely need for a procedure more invasive than a thoracentesis?

Answer 20

In increasing order of importance:

1. Loculated pleural fluid
2. Pleural fluid pH

Question 21

What to do if the fluid recurs after the initial therapeutic thoracentesis?

Answer 21

inserting a chest tube and instilling the combination of a fibrinolytic agent (e.g., tissue plasminogen
activator, 10 mg) and deoxyribonuclease (5 mg) or performing a thoracoscopy with the breakdown of adhesions. Decortication should be considered when these measures are ineffective.

Question 22

Which is the second most common type of exudative pleural effusion?

Answer 22

Malignant pleural effusions secondary to metastatic disease

Question 23

How do you treat chronic dyspneia in effusion secondary to malignancy?

Answer 23

(1) insertion of a small indwelling catheter or (2) tube thoracostomy with the instillation of a sclerosing agent such as doxycycline (500 mg).

Question 24

What is the presentation of patients with mesothelioma?

Answer 24

Patients with mesothelioma present with chest pain and shortness of breath.

Question 25

How is the the chest radiograph of a patient with mesothelioma?

Answer 25

the chest radiograph reveals a pleural effusion, generalized pleural thickening, and a shrunken hemithorax.

Question 26

If the pleural effusion increases in size after anticoagulation, what could be happening?

Answer 26

If the pleural effusion increases in size after anticoagulation, the patient probably has recurrent emboli or another complication, such as a hemothorax or a pleural infection.

Question 27

Mechanism for Tuberculous Pleuritis?

Answer 27

Tuberculous pleural effusions usually are associated
with primary TB and are thought to be due primarily to a hypersensitivity reaction to tuberculous protein in the pleural space.

Question 28

How do you diagnose Tuberculous Pleuritis?

Answer 28

The diagnosis is established by demonstrating high
levels of TB markers in the pleural fluid (adenosine deaminase more than 40 IU/L or interferon γ more than 140 pg/mL). Alternatively, the diagnosis can be
established by culture of the pleural fluid, needle biopsy of the pleura, or thoracoscopy.

Question 29

% of exudative effusions with no diagnosis?

Answer 29

no diagnosis is established for ~20% of exudative effusions, and these effusions resolve spontaneously with
no long-term residua

Question 30

What are the causes of chylothorax?

Answer 30

The most common cause of chylothorax is trauma (most frequently thoracic surgery), but it also may result from tumors in the mediastinum.

Question 31

Patients with chylothorax have what triglyceride level in the pleural fluid?

Answer 31

triglyceride level that exceeds 1.2 mmol/L (110 mg/

dL).

Question 32

What is the treatment for chylothoraxes?

Answer 32

The treatment of choice for most chylothoraxes is
insertion of a chest tube plus the administration of octreotide. If these modalities fail, a pleuroperitoneal shunt should be placed unless the patient has chylous ascites. Alternative treatments are ligation of the
thoracic duct and percutaneous transabdominal thoracic duct blockage.

Question 33

When is the patient considered to have a hemothorax?

Answer 33

If the hematocrit is more than one-half of that in the peripheral blood, the patient is considered to have a hemothorax.

Question 34

How do you treat a hemothorax?

Answer 34

Most patients with hemothorax should be treated with tube thoracostomy, which allows continuous quantification of bleeding.
If the bleeding emanates from a laceration of the pleura, apposition of the two pleural surfaces is likely to stop the bleeding. If the pleural hemorrhage exceeds 200 mL/h, consideration should be given to thoracoscopy or thoracotomy.

Question 35

If the pleural fluid amylase level is elevated, what diagnosis should we think of?

Answer 35

If the pleural fluid amylase level is elevated, the diagnosis
of esophageal rupture or pancreatic disease is likely.

Question 36

An intraabdominal abscess can cause what type of pleural effusion?

Answer 36

If the patient is febrile, has predominantly polymorphonuclear cells in the pleural fluid,
and has no pulmonary parenchymal abnormalities.

Question 37

Meigs’ syndrome

Answer 37

Benign ovarian tumors can produce ascites and a pleural effusion.

Question 38

Characteristics of pleural effusion after coronary

artery bypass surgery?

Answer 38

Effusions occurring within the first weeks are typically left-sided and bloody, with large numbers of eosinophils, and respond to one or two therapeutic thoracenteses. Effusions occurring after the first few weeks are typically left-sided and clear yellow, with predominantly small lymphocytes, and tend to recur.

Question 39

Define spontaneous pneumothorax; primary spontaneous pneumothorax; secondary pneumothorax; traumatic pneumothorax and tension pneumothorax.

Answer 39

spontaneous pneumothorax is one that occurs without antecedent trauma to the thorax. A primary spontaneous pneumothorax occurs in the absence of underlying lung disease, whereas a secondary pneumothorax occurs in
its presence. A traumatic pneumothorax results from penetrating or nonpenetrating chest injuries. A tension pneumothorax is a pneumothorax in which the pressure in the pleural space is positive throughout the respiratory cycle.

Question 40

% of patients with an initial primary spontaneous pneumothorax that will have a recurrence?

Answer 40

Approximately one-half.

Question 41

% of recurrences prevented by thoracoscopy or thoracotomy?

Answer 41

Thoracoscopy or thoracotomy with pleural abrasion is almost 100% successful in preventing recurrences.

Question 42

Biggest cause of secondary pneumothoraxes?

Answer 42

Most secondary pneumothoraxes are due to chronic obstructive pulmonary disease.

Question 43

What are the leading causes of iatrogenic pneumothorax?

Answer 43

transthoracic needle aspiration, thoracentesis, and the insertion of central intravenous catheters.