Dialysis

Question 1

what does dialysis do?

Answer 1

removes urea, K+ and Na+ while infusing HCO3-

Question 2

restrictions on patients on dialysis

Answer 2

fluid
salt
K+
phosphate (phosphate binders should be taken with meals)

Question 3

two types of dialysis

Answer 3

haemodialysis

peritoneal dialysis

Question 4

upgraded version of HD

Answer 4

haemodiafiltration (HDF)

Question 5

how does HD work

Answer 5

solutes are dragged across a semi-permeable membrane in response to a pressure gradient

Question 6

how often is HD done?

Answer 6

hospital for 4 hours 3 times a week

gradual build-up to begin with

Question 7

vascular access options for HD

Answer 7

1. fistula

2. tunnelled venous catheter

Question 8

fistula in HD

Answer 8

artery and vein connected creating an enlarged vein which requires surgery and maturation for 6-12 weeks

Question 9

sites of fistula

Answer 9

radio-cephalic (RC AVF)
brachio-cephalic (BC AVF)
brachio-basilic transposition (BB AVF)

Question 10

adverse of fistula

Answer 10

surgery
cannot be used immediately
can reduce blood flow to distal arm

Question 11

describe tunnelled venous catheter

Answer 11

catheter inserted into a large vein (internal jugular) which can be used immediately

Question 12

adverse of tunnelled venous catheter

Answer 12

infection

blockage

Question 13

how does peritoneal dialysis work?

Answer 13

uses the peritoneal membrane to transfer substances

Question 14

can PD be done at home

Answer 14

yes

Question 15

two types of PD

Answer 15

continuous ambulatory PD (CAPD)

automated PD

Question 16

describe CAPD

Answer 16

4 x 2L bag exchange per day

Question 17

describe APD

Answer 17

1 bag all day and overnight machine controls fluid drainage

Question 18

adverse of PD

Answer 18

infection
peritoneal membrane failure
hernia (increased intra-abdominal pressure)
training required (begin with small volumes)

Question 19

complications of dialysis

Answer 19

hypotension
haemorrhage (rupture AVF)
arrhythmias (electrolyte imbalance)

Question 20

define intra-dialytic hypotension

Answer 20

myocardial stunning due to removal of large volumes of H2O 3 times a week leading to underfilling of intravascular space and low BP

Question 21

indications for dialysis

Answer 21

resistant hyperkalaemia
eGFR <7ml/min
urea >40mmol/L 
unresponsive acidosis
symptomatic e.g. itch, fluid overload, fatigue, anorexia