Body Fluids- Serous Fluids

Serous fluid

Ultrafiltrate of plasma found between serous membranes that lubricates organs

Pleural fluid

Serous fluid located between the lungs and chest wall

Peritoneal fluid

peri-Serous fluid in the abdominal cavity also called ascitic fluid

Pericardial fluid

Serous fluid located between the pericardial membranes of the heart

Parietal membrane

Serous membrane lining the cavity wall

Visceral membrane

Serous membrane covering the organ surface

Effusion

Abnormal accumulation of serous fluid between membranes

Ascites

Excess accumulation of peritoneal fluid

Thoracentesis

Needle aspiration of pleural fluid

Paracentesis

para-Needle aspiration of peritoneal fluid

Pericardiocentesis

Needle aspiration of pericardial fluid

Formation of serous fluid

Occurs by ultrafiltration of plasma with no secretory process

Hydrostatic pressure

Pushes fluid out of capillaries into serous spaces

Oncotic pressure

Pulls fluid back into capillaries via plasma proteins

Capillary permeability

Increased during inflammation allowing proteins and cells to escape

Lymphatic drainage

Primary route for removal of excess serous fluid

Cause of effusion increased hydrostatic pressure

Congestive heart failure

Cause of effusion decreased oncotic pressure

Hypoproteinemia or liver disease

Cause of effusion increased permeability

Inflammation or infection

Cause of effusion lymphatic obstruction

Malignancy

Transudate

Serous fluid caused by systemic factors without inflammation

Transudate appearance

Clear and pale yellow

Transudate protein ratio

Fluid protein to serum protein less than 0

5

Exudate

Serous fluid caused by inflammation or malignancy

Exudate appearance

Cloudy and may clot

Exudate protein ratio

Fluid protein to serum protein greater than 0

5

LD ratio transudate

Fluid LD to serum LD less than 0

6

LD ratio exudate

Fluid LD to serum LD greater than 0

6

Mesothelial cells

Normal lining cells with fried egg appearance

Neutrophils in serous fluid

Indicate acute bacterial infection

Lymphocytes in serous fluid

Suggest tuberculosis or malignancy

Malignant cells in serous fluid

Indicate metastatic cancer

CEA

Tumor marker elevated in malignant effusions

Amylase in serous fluid

Elevated in pancreatic disease or esophageal rupture

Triglycerides in serous fluid

Elevated in chylous effusions from lymphatic obstruction

Serum ascites albumin gradient

Serum albumin minus ascitic fluid albumin

High SAAG

Greater than 1

1 indicating portal hypertension

Low SAAG

Less than 1

1 indicating non-hepatic causes