Dialysis

Question 1

all patients with CKD will end up with ESKD without treatment T or F

Answer 1

F, most will probably die before then

Question 2

name the 3 concepts of dialysis

Answer 2

diffusion
convection
adsorption

Question 3

why is diffusion used in dialysis?

Answer 3

allows toxins that build up to exit the blood eg urea, K+, Na+

Question 4

what do you want to infuse in dialysis and why?

Answer 4

bicarb to fix metabolic acidosis

Question 5

what substances do you want to remove in dialysis?

Answer 5

K
urea
Na
creatinine

Question 6

what does a dialysis machine try to imitate?

Answer 6

a functional kidney

Question 7

how much Na do you want to remove and why?

Answer 7

not much as dont want lots of salt and water to leave

Question 8

what is ultrafiltration?

Answer 8

solutes moving with water across a semi-permeable membrane in response to a pressure gradient

Question 9

what happens in a high flux membrane?

Answer 9

pores get bigger to allow bigger substances eg protein bound solutes in

Question 10

a high flux membrane is present at what stage of dialysis?

Answer 10

adsorption

Question 11

plasma protein movement across the membrane is principally achieved in what stage of dialysis?

Answer 11

adsorption

Question 12

what is a convective solute drag?

Answer 12

dissolved solutes in water will move with it in response to pressure

Question 13

dialysis only has access to the ___ of the body

Answer 13

circulation

Question 14

haemodialysis is primarily a __ process

Answer 14

diffusive

Question 15

haemodiafiltration is primarily a __ process

Answer 15

convective

Question 16

haemodiafiltration relies on what process?

Answer 16

convective solute drag

Question 17

what affects how well a substance is transported across the membrane in HDF?

Answer 17

water flux
membrane pore size (big/small holes)
pressure difference
viscosity
size, shape and charge of molecule

Question 18

minimum dialysis time per week?

Answer 18

4hrs 3 times per week

Question 19

what dietary changes does a patient on dialysis have to make?

Answer 19

low salt diet
low potassium diet
if anuric can only drink 1l of water
low phosphate diet

Question 20

gold standard method of accessing the circulation for dialysis?

Answer 20

fistula

Question 21

what is a fistula?

Answer 21

joining and artery and a vein to make an enlarged vessel - the arteriovenous fistula (AVF)

Question 22

most common vessels chosen for a fistula?

Answer 22

brachial artery and cephalic vein

Question 23

what was the original form of circulatory access for dialysis?

Answer 23

scribner shunt

Question 24

complications of an arteriovenous fistula?

Answer 24

steal syndrome - ischaemia of the hand

Question 25

what dialysis circulatory access is used for late presenting patients?

Answer 25

tunnelled venous catheter

Question 26

what circulatory dialysis access method puts the patient at highest risk of infection?

Answer 26

tunnelled venous catheter

Question 27

what vein is the tunnelled venous catheter inserted into?

Answer 27

jugular or subclavian vein

Question 28

untreated tunnelled venous catheter infection can lead to what problems?

Answer 28

endocarditis discitis death

Question 29

what organism is most likely to cause a tunnel venous catheter infection?

Answer 29

staph aureus or other gram +ves

Question 30

Tx of a tunnelled venous catheter infection?

Answer 30

vancomycin +/- gentamicin

Question 31

main complications of dialysis?

Answer 31

``` hypotension blood leaks from fistulae loss of vascular access hyperkalaemia cardiac arrest ```

Question 32

what causes hypotension in dialysis patients?

Answer 32

myocardial stunning from dialysis | losing large volumes of water

Question 33

how is solute removed in peritoneal dialysis?

Answer 33

diffusion

Question 34

how is water removes in peritoneal dialysis?

Answer 34

osmosis

Question 35

what drives the water out in peritoneal dialysis?

Answer 35

the high glucose conc in dialysate fluid

Question 36

does glucose move in or out of the peritoneal cavity in peritoneal dialysis?

Answer 36

in

Question 37

standard prescription of continual peritoneal dialysis?

Answer 37

4 2l bag exchanges per day

Question 38

how is automated peritoneal dialysis different from continual?

Answer 38

only 1 bag is used rather than 4

Question 39

main complications of peritoneal dialysis?

Answer 39

infection peritoneal membrane failure hernias (inc abdo pressure)

Question 40

what investigation should you do for a peritonitis caused by dialysis?

Answer 40

culture peritoneal dialysate fluid

Question 41

how long should the first HD session be? what should this build up to

Answer 41

2hrs | build up to 4hrs

Question 42

what medical conditions should prompt withdrawal from dialysis?

Answer 42

PVD stroke CVD cancer