Dialysis

Question 1

end stage renal disease can be caused by

Answer 1

stage 5 chronic kidney disease or failure of recovery from an AKI

Question 2

without renal replacement therapy end stage renal disease will cause

Answer 2

death very quickly

Question 3

what is the best form of renal replacement therapy

Answer 3

transplant however, because of the shortage of organs most people have to be started on dialysis while they wait

Question 4

dialysis is used to prevent

Answer 4

life threatening hyperkalaemia, metabolic acidosis and pulmonary oedema

Question 5

modern renal replacement uses dialysis to remove

Answer 5

unwanted solutes by filtration and remove water by haemofiltration which carries with it unwanted soluble substances

Question 6

the principle of dialysis

Answer 6

if blood is separated from a fluid by a semi-permeable membrane then electrolytes and other substances diffuse across the membrane until equilibrium is achieved in haemodialysis a synthetic membrane is used while in peritoneal dialysis the persons own peritoneum is used

Question 7

principle of haemo-filtration

Answer 7

similar to glomerular filtration, if blood is pumped at a higher hydrostatic pressure than the fluid on the other side of the semi-permeable membrane then the water in the blood is forced through the membrane by ultrafiltration and carries with it dissolved electrolytes

Question 8

practical aspects of haemodialysis

Answer 8

in haemodialysis blood is pumped past one side of a semi-permeable membrane while the dialysate is pumped past the other side in the opposite direction

Question 9

the amount of fluid removed by ultra-filtration can be controlled by

Answer 9

controlling the hydrostatic pressure of the blood in comparison with the dialysate

Question 10

the dialyse fluid is composed of

Answer 10

essentail component of the plasma, sodium, potassium, chloride, glucose, magnesium, glucose and a buffer such as bicarboante

Question 11

the plasma concentration can be controlled by

Answer 11

altering the composition of the dialyse i.e. there is less potassium in the dialyse to promote the movement of potassium from the blood into the dialysate

Question 12

what else is in the dialyse

Answer 12

heparin to prevent clotting

Question 13

access for dialysis

Answer 13

arteriovenous fistula but this takes a surgery and a few months to form therefore if access required urgently central census catheter

Question 14

acute complications of dialysis

Answer 14

• overaggressiveness can cause hypovoalemia and dialysis disequilibrium syndrome
• dialysis disequilibrium syndrome caused by osmotic changes in the brain as plasm urea follows
• cramps can occur and an itch caused by a ild allergic reaction to the semi-permeable membrane

Question 15

chronic complications of dialysis

Answer 15

• fistula, thrombosis, aneurysm formation, infection
• patients have to limit there fluid intake between dialysis sessions
• patients should reduce sodium intake to reduce thirst

Question 16

peritoneal dialysis

Answer 16

dialysate is infused into the peritoneal cavity through a tube and water and solutes then diffuse across the peritoneal membrane

Question 17

in peritoneal dialysis

Answer 17

water moves by osmosis because the dialyse contains glucose which also causes solutes to move via diffusion

Question 18

continuers ambulatory peritoneal dialysis requires

Answer 18

the patient to change there 2 litre bag every 4 hours

Question 19

complications of peritoneal dialysis

Answer 19

infection is the most common complication and is most commonly caused by staph epidermis

Question 20

repeated peritonitis in people with peritoneal dialysis can

Answer 20

reduce the permeability of the semi-permeable membrane

Question 21

continous haemofiltratioen

Answer 21

venous bloos is pumped at a high pressure onto a highly permeable membrane producing large volumes of unltrafiltrate which is then discarded and replaced by an appropriate volume of balaned electrolyte solution which is added back to the blood

Question 22

continuous haemofiltration

Answer 22

is a continuous process and is slower than dialysis s is more suitably for crticillay ill or haemodynamically unstable as it avoids rapid changes in solute concentraiotn