Dialysis

Question 1

name the 3 concepts related to dialysis

Answer 1

diffusion
convection
adsorbtion

Question 2

define diffusion

Answer 2

movement of solutes from high to low concentration to equalise the gradient

Question 3

what does dialysis allow the removal of?

Answer 3

toxins which build in ESRD

urea
creatinine
potassium
sodium

Question 4

what does dialysis allow the infusion of?

Answer 4

allow infusion of bicarbonate

pure H2O

Question 5

the movement of water (and all solutes dissolved in it- convective solute drag) across a semi-permeable membrane in response to a pressure gradient

the above defines what?

Answer 5

convection

Question 6

what is convection also known as?

Answer 6

ultrafiltration

Question 7

what does adsorption affect?

Answer 7

plasma proteins

Question 8

____ flux membranes adsorb protein-bound solutes better than ___ flux membranes

Answer 8

HIGH flux membranes adsorb protein-bound solutes better than LOW flux membranes

Question 9

where do plasma proteins stick?

Answer 9

membrane surface and removed by membrane binding

Question 10

______________ is diffusive but ___________________ is convective in nature

Answer 10

HAEMODIALYSIS is diffusive but HAEMODIAFILTRATION is convective in nature

Question 11

in HDF, lots of things affect the efficiency of the convective transport. name some.

Answer 11

water flux
membrane pore size
pressure difference
fluid viscosity
shape, size and electrical charge of each molecule

Question 12

what is the minimum HD/HDF prescription?

Answer 12

4 hours 3 times per week

Question 13

decreasing HD time by __ mins increases your risk of death by 1%

Answer 13

decreasing HD time by 30 mins increases your risk of death by 1%

Question 14

restriction for HD patients:

low… (4)

Answer 14

low fluid
low salt
low potassium
low phosphate

Question 15

name the vessel that tunnelled venous catheters are usually placed into

Answer 15

internal jugular vein

Question 16

infections in tunnelled venous catheters are caused by what organism?

Answer 16

staph. aureus

Question 17

treatment of infected tunnelled venous catheters?

Answer 17

vancomycin and gentamicin

Question 18

what is the gold standard for dialysis vascular access?

Answer 18

fistula

Question 19

sites for fistulas?

Answer 19

radio-cephalic
brachio-cephalic
brachio-basilic transposition

Question 20

pros and cons of fistula?

Answer 20

pros:

good flow and less likely to cause infection

cons:

surgery
can’t use for 6-12 weeks
‘steal arm’ - limit flow to distal arm
thrombose/stenose

Question 21

state the acronym for haemodialysis reliable outflow graft

Answer 21

HeRO graft

Question 22

what can go wrong in dialysis?

Answer 22

hypotension
haemorrhage
loss of vascular access
arrhythmia
cardiac arrest

Question 23

water is removed via _______ in peritoneal diffusion

Answer 23

water is removed via OSMOSIS in peritoneal diffusion

Question 24

how is PD driven?

Answer 24

high glucose concentration in dialysate fluid

Question 25

name the 2 types of PD

Answer 25

CAPD - continuous ambulatory peritoneal dialysis

APD - automated peritoneal dialysis

Question 26

which PD is at night and which is 4 x 2L bags per day?

Answer 26

APD - night

CAPD - 4 x 2L bags

Question 27

PD complications?

Answer 27

infection - peritonitis

peitoral membrane failure

hernias

Question 28

when do you start dialysis?

potassium?
eGFR?
urea?
metabolic acidosis?

Answer 28

resistant hyperkalaemia
eGFR < 7 ml/min
urea >40 mmol/L
unresponsive metabolic acidosis

Question 29

when to start dialysis on symptoms?

Answer 29

nausea
vomiting
anorexia
fatigue
itch