Dialysis

Question 1

what is diffusion?

Answer 1

the process by which particles move from an area of high concentration to an area of low concentration, across a semi-permeable membrane

Question 2

name two factors that affect diffusion

Answer 2

concentration gradient

molecular weight of solute

Question 3

name four toxins that can be removed by dialysis

Answer 3

urea
creatinine
potassium
sodium

Question 4

what can be infused during dialysis and how?

Answer 4

bicarbonate

concentration is higher in the dialysate than the blood so it diffuses

Question 5

what flow rate is required for haemodialysis to be effective?

Answer 5

300-350 ml/min

Question 6

what are the four vascular access options for haemodialysis?

Answer 6

arteriovenous fistula
arteriovenous graft
tunnelled central venous catheter
temporary venous catheter

Question 7

what is another name for a temporary venous catheter?

Answer 7

vasacath

Question 8

what vascular access would be used in someone requiring acute short term dialysis?

Answer 8

temporary venous catheter

Question 9

at what rate is dialysate usually ran at in haemodialysis?

Answer 9

500ml/min

= around 120L in a four hour treatment

Question 10

what does dialysate consist of?

Answer 10

pure water
electrolytes (Na, K, HCO3)
glucose

Question 11

how is excess fluid removed from a patients blood during dialysis?

Answer 11

a pressure gradient is set up between blood and dialysate

this forces water and all of the solutes in it to leave the blood

Question 12

what is the movement of water out of the blood in dialysis called?

Answer 12

the convective solute drag

Question 13

what is the whole process of water loss and the solute drag in dialysis called?

Answer 13

ultrafiltration

Question 14

what is the usual range set for ultrafiltration in a dialysis session?

Answer 14

1-3L

Question 15

what is affected by adsorption?

Answer 15

plasma proteins

any solutes bound to them

Question 16

what happens to plasma proteins in adosrption?

Answer 16

become stuck to the membrane of the dialysis kidney

removed by membrane binding

Question 17

how is most solute removed in haemodialysis?

Answer 17

diffusion

Question 18

how is most solute removed in hemodiafiltration?

Answer 18

convection

massive amounts of ultrafiltration

Question 19

what defines high volume hemodiafiltration?

Answer 19

replacement volumes of >21 L

Question 20

what can improve the efficiency of dialysis?

Answer 20

longer treatment times

Question 21

what is the usual dialysis schedule?

Answer 21

four hours

three times a week

Question 22

what four things need to be restricted in the diet if someone is on dialysis?

Answer 22

fluid
salt
potassium
phosphate

Question 23

how much fluid can an anuric dialysis patient consume a day?

Answer 23

one litre

Question 24

how much salt should a dialysis patient consume per day?

Answer 24

less than 2.3g

Question 25

if the phosphate levels remain high in a dialysis patient, what do they need to take?

Answer 25

phosphate binders with meals

Question 26

what is a tunnelled central venous catheter?

Answer 26

a catheter inserted into a large vein

Question 27

what vein is often used for a TCVC?

Answer 27

internal jugular

Question 28

what are the pros of TCVC?

Answer 28

easy to insert | can be used immediately

Question 29

what is there high risk of in a TCVC?

Answer 29

infection

Question 30

what is the most common cause of an infection of a TCVC?

Answer 30

staph aureus

Question 31

what antibiotics should be given for an infected TCVC?

Answer 31

vancomycin and gentamicin

Question 32

what is the gold standard for dialysis vascular access?

Answer 32

an arteriovenous fistula

Question 33

what is an AVF?

Answer 33

when an artery and vein are surgically created for dialysis access

Question 34

what are the three possible sites for an AVF?

Answer 34

radio cephalic brachio cephalic brachio basilic transposition

Question 35

how is an AVF formed?

Answer 35

surgically

Question 36

when can an AVF be used?

Answer 36

after a maturation period of 6-12 weeks

Question 37

what is it called when an AVF limits blood flow to the distal arm?

Answer 37

steal syndrome

Question 38

if a patient cannot have an AVF, what are the next best options?

Answer 38

arteriovenous graft | HeRo graft

Question 39

what is a life threatening complication of an AVF?

Answer 39

rupture causing massive haemorrhage

Question 40

what acts as the semi permeable membrane in peritoneal dialysis?

Answer 40

the peritoneum

Question 41

how are solutes removed in peritoneal dialysis?

Answer 41

by diffusion of solutes across the peritoneal membrane

Question 42

how is water removed in peritoneal dialysis?

Answer 42

osmosis driving by the high glucose concentration of the dialysate

Question 43

what are the two types of peritoneal dialysis available?

Answer 43

continuous ambulatory peritoneal dialysis (CAPD) automated peritoneal dialysis (APD)

Question 44

which PD is done overnight?

Answer 44

automated PD

Question 45

what are three possible complications of peritoneal dialysis?

Answer 45

infections peritoneal membrane failure hernias

Question 46

what needs to be done if there is peritoneal membrane failure in someone on peritoneal dialysis?

Answer 46

switch to haemodialysis