Lymphydema Flashcards
(129 cards)
What are the causes of ACTIVE hyperemia
Anything that causes a greater demand for blood
Inflammation, infection, heat, friction, trauma, exercise
What are the causes of PASSIVE hyperemia
Anything that causes obstruction of the venous outflow
DVT, CHF, CVI (chronic venous insufficiency), Tumor
What is the mechanism for both passive and active hyperemia?
Vasodilation!
Name the major mechanism difference (and location of mechanism) between active and passive hyperemia
Active: due to increased blood flow on the pre-cap arterioles
Passive: due to obstruction on the venous side of the capillary bed
What is the result of both active and passive hyperemia?
Ultrafiltration: pressure in blood capillaries forces water to leave blood into the interstitium
What was starlings original equation?
Average BCP = COPp
In Starlings original equation (BCP =COPp) what did greater BCP cause?
Greater COPp cause?
BCP»_space;> COPp = ultrafiltration
COPp»_space;> BCP = reabsorption
What is the primary source of cellular nutrition?
Diffusion
How does diffusion proceed?
high to low concentration
How is diffusion measured?
L/min of flow
What is osmosis
Specialized diffusion through a semi-permeable membrane (capillaries)
Therefore generally water is moving from an area of low substrate concentration to an area of high to dilute it
Osmosis generally has a small contribution to normal nutrition of cells, diffusion mainly takes care of this. However, in what circumstances does osmosis become an important part of cell nutrition?
Disease states
How much flow volume is normal / day for osmosis?
2-4 L/day
Protein has a strong or high affinity for water
high
What is Albumin’s function
hold onto fluid volume in the blood
Its the primary protein in the blood
Why does COP develop?
Bc protein affinity to bind with water
What is the COP of plasma?
7g/% = 25 mmHg
What is ultrafiltration?
Hydraulic pressure of the blood capillaries forcing an additional amount of water to leave the blood and enter the interstitial space
When blood enters the capillary bed compare BCP to COPp and what this relationship creates.
BCP»_space; COPp
BCP wants to push water out and it wins out, therefore water moves into the interstitium
True or False: pre-capillary arterioles are passive structures?
False! they are highly muscularized and innervated by the ANS
Responsible for vasodilation and constriction which we know affects capillary pressure
What is the relationship between arterial BP and BCP
Decrease in arterial BP (due to vasodilation) = increase in BPC due to the greater influx of blood
What happens to central blood pressure when vasodilation occurs? BCP?
Central blood pressure: drops
BCP: increases
What is the result of both active and passive hyperemia
Ultrafiltration
Is BPC hydrostatic or osmotic?
Hydrostatic