Lec 13-FLUIDS LEC

Question 1

What is the cause of pleural effusion?

Answer 1

Increased production of the pleural fluid and decreased drainage

Question 2

What are the 4 groups of pleural fluid?

Answer 2

• Exudate Effusion: Characterized by altered pleural membranes associated with
  increased permeability
• Transudate Effusion: Characterized by increased
  hydrostatic pressure or
  decreased oncotic pressure
• Chylothorax: Pleural effusion due to damage of the thoracic
  duct. Damage to or rupture of the thoracic duct
  may cause a leakage of chyle into the pleural
  space.
• Pseudochylothorax: Pseudochylothorax is
  mainly composed of
  cholesterol and commonly
  develops from cell debris
  present in the pleural fluid
  for a long period of time

Question 3

Name 5 biochemical tests used to differentiate between the exudate and transudate pleural effusions

Answer 3

total protein, LDH, glucose, albumin, and pH

Question 3

Pleural fluid is classified as a transudate or exudate based on modified_________

Answer 3

Light’s criteria

Question 3

When do ascites occur?

Answer 3

Ascites occurs when there is imbalance of plasma flowing in and out of the blood and lymphatic vessels or if there is inflammation or injury.

Question 4

Pleural fluid is considered exudative effusion if at least one of the criteria
are met:

Answer 4

-Pleural fluid protein/serum protein ratio more than 0.5
-Pleural fluid lactate dehydrogenase (LDH)/serum LDH ratio of more than
0.6
-Pleural fluid LDH is more than 200 u/L.

Question 5

What is SAAG (Serum Ascites Albumin gradient)?

Answer 5

It is the difference between serum albumin and ascitic
fluid albumin. It is used to differentiate the causes of ascites.

*SAAG is a reliable marker distinguishing ascites related to portal hypertension from all
other causes of ascites.

Question 6

Name 2 groups of ascites based on their SAAG

Answer 6

• SAAG of > 11g/L (Transudative ascites)
• SAAG of < 11 g/L (Exudative ascites)

Question 7

What causes transudate effusion and exudate effusion in the pericadium of the heart?

Answer 7

Transudate: Results from obstruction of fluid drainage
through lymphatic channels.

Exudate: Reflect inflammatory, infectious, malignant, or
autoimmune processes within the pericardium

Question 8

Name the 2 most common biochemical tests for pericadium effusion

Answer 8

• Lactate Dehydrogenase (LDH)
• and Total Protein

Question 9

Name the primary laboratory tests used in initial investigations of pericardial effusions of unclear aetiology

Answer 9

• Cytological examination as well as
• bacteriologic smears
• and cultures of fluid