(04-02) - Renal Blood flow

Question 1

Question 2

might be a good idea to listen to this case example if you have time

around

30:00 on 4/29 9AM

Answer 2

higher creatinine number = lower the kidney function

creatinine is the measure of the glomerular filtration rate - whihc is primary indicatro kidney function

BUN = blood-urea-nitrogen - like creatinine both are influenced by glomerular filtartion rate - but BUN affected by things beyond it - like what you eat - not as good of an indicator as creatinine

when we see USG values of below 1040 - we will assume that this is due to some kind of kidney dystfunction and sn’t just dehyrdation

also has protein in urine (which isn’t suppose to happen)

Question 3

Answer 3

why did PCV go up? dehyrdation

why did creatinine go up? glomerular filtration rate is worse

why is BUn higher - happen with dehyrdation

urine less concentrated? suggests problem with kidney

What happened? we will come back to it…

Question 4

(Some Definitions)

1. renal blood flow = ?
2. What is renal plasma flow?
3. glomerular filtration rate = ?
4. filtration fraction = ?

Answer 4

1. amount of blood that flows through kidney per unit of time (measured as ml/min)
2. RPF = RBF * (Hct-1)

(tend to focus on plasma a bit more because that deals more iwth what we can generate in terms of filtration ??)

3. amount of filtrate per unit time (ml/min)
4. GFR/RPF

Question 5

this is review….

Question 6

(Key Points)

1. The kidneys receive and enourmous amount of blood flow - however, it is regionally distributed
2. most flows through the efferent arterioles into the what of the what?
3. what percent flow through medulla?
4. Renal blood flow far exceeds the metabolic requirement for the kidneys - why so much then?

Answer 6

2. the peritubular capillaries of the cortex
3. 5-10%
4. required for fuctional reasons

Question 7

(Key Points)

1. the kidney has two capillary beds in series
2. Why is renal cortical blood flow unique?

Answer 7

2. arterioles entering (afferent) and leaving (efferent) the glomerular capillaries contain sphincters that allow modulation of renal blood flow and pressure within the glomerular capillaries

glomerulus = high pressure

second bed (peritubular capillaries) = low pressure

Question 8

(Two Major Factors of Filtration)

1-4. what are the four?

Answer 8

Question 9

(Pressure)

1. Kidney function depends on the hydraulic pressure in blood vessels
2. what is hydraulic pressure?
3. reistance in vessels - resistance to flow of liquids

Answer 9

2. pressure resulting from the effects of liquids

Question 10

if you constrict the pre-glomerular (or afferent arteriole) - will decrease flow in the glomerulus - pressure will go down and therefore filtration - will make higher pressure upstream - but not downstream where filtartion is occuring