Vascular Physiology

Question 1

Lymphatic System

Answer 1

-net exiting of H2O is picked up by lymphatic system

Question 2

Venous Return Influenced By:

Answer 2

• distensibility of veins
• pressure gradient
• sympathetic NS
• Skeletal Mm Activity
• Venous Valves
• Cardiac Suction
• Respiratory Activity (inhale cause decrease pressure in chest so blood flows to heart)

Question 3

JVD

Answer 3

• tests right side of heart
• distention of jugular veins
• Positive Test=bilateral distention of Vv above clavicle with head elevated to 45*

Question 4

How do capillaries control where blood is directed?

Answer 4

• the precapillary sphincters act as local controls to divert blood to needed areas (esp when sympathetic NS is signaling widespread vasoconstriction)
• like during exercise

Question 5

Hepatojugular Reflex

Answer 5

• Test right side of heart

- push on liver 20-30 sec to squeeze out blood and see if jugular veins become distended

Question 6

Pressure Application

Answer 6

• Arterial side: total pressure=net H2O movement outward

- Venous Side: total pressure=net H2O movement inward

Question 7

CVP

Answer 7

• central venous pressure
• Increased CVP: from heart failure when blood can’t leave R atrium, or large blood transfusion
• Decreased: from R atrium contracting with more than normal force, or decreased venous return

Question 8

HP(c)

Answer 8

• capillary BP
• hydrostatic pressure on inside of capillary by blood
• increased @ arterial side of cap
• decreased at venous side of cap

-CAUSES H2O TO MOVE OUT OF CAPILLARY

Question 9

HP(if)

Answer 9

• interstitial fluid hydrostatic pressure
• pressure of interstitial fluid outside the capillary pushing H2O into cap

(very small pressure)

Question 10

OP(if)

Answer 10

• interstitial fluid oncotic pressure
• proteins pull H2O to them
• small amt proteins outside cap to pull H2o out of cap

(very very small pressure)

Question 11

OP(p)

Answer 11

• plasma-colloid oncotic pressure
• proteins pull H20 to them
• more proteins in capillary than out so H20 moves into cap