Lecture 4 - Flow & Starling Forces

Question 1

Blood flows from ____ pressure to ___ pressure

Answer 1

higher; lower

Question 2

arteries are considered ___ pressure while veins are considered ___ pressure

Answer 2

high; low

Question 3

what two main factors impact fluid flow

Answer 3

1. viscosity
2. density

Question 4

blood flow is directly proportional to

Answer 4

the pressure difference between two points

Question 5

blood flow is inversely proportional to

Answer 5

the resistance between two points

Question 6

what is the greatest factor in changing resistance

Answer 6

radius of tube (dilation or constriction)

Question 7

where is peripheral vascular resistance found

Answer 7

smaller arteries and arterioles

Question 8

what 3 factors determine resistance

Answer 8

1. viscosity
2. vessel length
3. vessel diameter

Question 9

if a liquid is more viscous is the resistance more or less?

Answer 9

more

Question 10

if a tube is longer is the resistance more or less?

Answer 10

more

Question 11

if the tube is small in diameter is the resistance more or less?

Answer 11

more

Question 12

Which of the following changes would DECREASE blood flow in a vessel?

a. vasodilation
b. vasoconstriction
c. decreased viscosity

Answer 12

b. vasoconstriction

Question 13

Which patient below would you expect to have INCREASED absorption of water from the interstitial space INTO the blood vessel?

a. a cat with increased blood pressure
b. a cow with increased albumin concentrations in the blood
c. a horse with blood vessels “leaky” to water

Answer 13

b. a cow with increased albumin concentrations in the blood

Question 14

how does fluid movement across the cell wall differ to capillary diffusion

Answer 14

cell wall = osmotic pressure
capillary wall = oncotic and hydrostatic pressure

Question 15

Hydrostatic forces

Answer 15

push fluid out of the intravascular space based on pressure

Question 16

Oncotic forces

Answer 16

pull fluid to the intravascular space based on plasma proteins

Question 17

filtration

Answer 17

represents water movement out of the vascular space to the interstitium

Question 18

reabsorption

Answer 18

represents water movement from the interstitium into the plasma

Question 19

what 3 additional factors should be considered for filtration and resorption

Answer 19

1. permeability of capillary wall to water
2. reflection coefficient of proteins
3. lymph flow

Question 20

how does the lymphatic vasculature impact hemodynamics

Answer 20

returns lost plasma volume and proteins to the systemic venous circulation

Question 21

how do lymph capillaries differ from blood vasculature

Answer 21

specialized to allow large molecules to diffuse

Question 22

what allows lymphatic capillaries to be so permeable

Answer 22

1. no tight junctions
2. collagen filaments anchor endothelial cells to increase volume

Question 23

T/F: the thoracic duct is the largest lymphatic vessel

Answer 23

TRUE

Question 24

what 4 things alter starling forces

Answer 24

1. change in oncotic pressure (protein concentration)
2. changes in hydrostatic pressure (hypo-/hyper- tension)
3. changes in permeability of capillaries
4. changes in lymph removal

Question 25

what is the endothelial glycocalyx

Answer 25

gel-like matrix that lines all vascular endothelial surfaces

Question 26

what 4 categories can edema be divided into

Answer 26

1. increased capillary hydrostatic pressure
2. decreased plasma oncotic pressure
3. enhanced permeability of capillaries
4. lymphatic obstruction/decreased return

Question 27

R-sided heart failure causes increased pressure and edema where

Answer 27

abdomen