Renal Replacement Therapy

Question 1

What is renal replacement therapy?

Answer 1

Dialysis

Kidney transplant

Question 2

List 5 indications for renal replacement therapy.

Answer 2

Hyperkalaemia
Fluid overload
Uraemia
Acidosis
Presence of severe CKD symptoms

Question 3

What are the 3 types of dialysis?

Answer 3

Haemodialysis (HD)
Peritoneal dialysis (PD)
Continuous veno-venous dialysis (CVVD)

Question 4

Describe how haemodialysis is carried out. (3)

Answer 4

1. Surgical arteriovenous fistula formation
   a. Takes 6-8 weeks to be ready for dialysis
   b. If no time for fistula formation, then use a tunneled line
2. Blood is taken out of the patient
   a. Electrolytes diffuse out down a concentration gradient
   b. Fluid moves down an osmotic gradient via convection
3. Blood is transfused back into the patient
   a. Dialysate is discarded

Question 5

List 4 types of haemodialysis regimens.

Which one is standard?

Answer 5

Standard: 4 hours, 3 times a week

Other options:

• 6 hours, 3 times a week
• Short daily dialysis
• Daily, overnight dialysis

Question 6

List 8 complications of haemodialysis.

Answer 6

Hypotensive crash
Dialysis disequilibrium
Cramps
Fatigue
Hypokalaemia
Air embolism
Blood loss
Access problems

Question 7

Describe the mechanism of peritoneal dialysis. (2)

Answer 7

1. Dialysate is pumped into the peritoneal cavity; the peritoneal membrane acts as the semipermeable membrane between dialysate and blood
2. Dialysate is rich in glucose, creating an osmotic gradient for fluid to diffuse out of blood

Question 8

What are the 2 types of peritoneal dialysis? Briefly describe them.

Answer 8

Continuous ambulatory peritoneal dialysis (CAPD)
-Manual exchanges by patient

Automated peritoneal dialysis (APD)
-Machine exchanges dialysate automatically during sleep

Question 9

List 7 complications of peritoneal dialysis.

Answer 9

Infection
Increased glucose load (diabetes)
Mechanical problems (e.g. hernia, diaphragmatic leak, dislodged catheter)
Peritoneal membrane failure
Hypoalbuminaemia
Encapsulating peritoneal sclerosis

Question 10

List 4 contra-indications for peritoneal dialysis.

Answer 10

Grossly obese patients
Intra-abdominal adhesions
Frail patients
Unsuitable home environment

Question 11

Which type of dialysis would you use in AKI? Why?

Answer 11

Haemodialysis

HD is immediate, whereas PD only has a gradual effect

Question 12

What types of immunosuppression would you use in kidney transplants? (5)

Answer 12

INDUCTION:
Basilixumab
Alemtuzumab

MAINTENANCE:
Calcineurin inhibitors, e.g.
-Tacrolimus

Antimetabolites, e.g.
-Azathioprine

Prednisolone

Question 13

List 7 surgical complications of kidney transplants.

List 4 transplant complications.

Answer 13

SURGICAL COMPLICATIONS:
Death
Major medical events
Bleeding
Thrombosis
Haematoma
Wound infection
Ureteric leak

TRANSPLANT COMPLICATIONS:
Delayed graft function (DGF)
Hyperacute rejection
Acute rejection
Chronic allograft nephropathy

Question 14

Describe the 2 types of acute organ rejection.

Answer 14

Humoral (antibody-mediated)

Cellular

Question 15

How would you treat acute organ rejection? (3)

Answer 15

IV methylprednisolone
Increase immunosuppression
Plasma exchange

Question 16

Describe the pathophysiology of chronic allograft nephropathy. (2)

Answer 16

1. Chronic, low-grade antibody response attacks the transplanted kidney
2. Vascular changes damage the transplanted kidney

Question 17

How would you treat chronic allograft nephropathy? (1)

Answer 17

New transplant

Question 18

Which types of cancer are relatively more common in transplant patients (due to immunosuppression)? (2)

Answer 18

Lymphomas (post-transplant lymphoproliferative disorders)
Skin cancers (e.g. SCC, BCC)