AD Lecture #3

Edema

abnormal accumulation of fluid in the interstitial or extravascular space

What is edema caused by

Venous congestion!!!

intravascular

inside the vessel (plasma)

extravascular

outside the vessel; fluid in the tissue

What is oncotic (osmotic) venous pressure

Pressure used to pull fluid in the tissue back into the vessel due to high concentration of proteins in the vessel

How does fluid noramally stay in the vessels?

-vessels allow passage of fluid, not proteins

-proteins in vessels create oncotic pressure that draws fluid into vessel

-blood and tissue fluid pressure - arterial pressure

what is needed to maintain oncotic pressure?

Proteins in the vessel are needed

if there is a decreased amount of protein, what happens to the oncotic pressur?

Decreased oncotic pressure

What happens when hydrostatic and oncotic pressure are balanced

Homeostasis

What is hydrostatic arteriole pressure

The pressure that pushes fluid from the vessel into the tissue

What happens if hydrostatic pressure > osmotic pressure

Fluid exits vessel

what happens if hydrostatic pressure < osmotic pressure

fluid enters vessel

What are the four possible causes of edema?

-Increased hydrostatic pressure

-reduced oncotic pressure

-lymphatic obstruction

-sodium/water retention

Hydrothorax

fluid in thorax

what is plueral effusion

fluid in chest but outside of lung

what is pulmonary edema

effusion of fluid in the avioli of the lungs

hydroperitoneum

fluid in the abdomen (ascites)

hydropericardium

fluid around heart

anasarca

severe generalized edema with profound SQ tissue swelling

What role does the lymphatic system play?

It is the clean up crew that takes away excess fluid/waste from the tissue

How does heart failure result in edema?

causes an increase in hydrostatic pressure causes venous congestion = fluid out

how does liver disease result in edema?

Liver isn't producing as many proteins - a decrease in proteins = decrease in oncotic pressure = fluid out

how does inflammation cause edema?

increase in capillary permeability = fluid out

How does lymphatic obstruction cause edema

fluid out - can't take away excess fluid

Non-inflammatory edema

characterized by a lack of pain, heat and redness

What type of fluid is found with non-inflammatory edema: transuadate or exudate?

Transudate

Inflammatory edema

warm, red and painful

What type of fluid is found with inflammatory edema: transuadate or exudate?

exudate

Hyperemia

blood accumulates in an area due to an increase in blood flow

Congestion

Imparied flow of blood from tissue