Renal Replacement Therapy 1 (Dialysis)

Question 1

What syndrome does chronic kidney disease result in? What are the earliest cardinal symptoms of CKD?

Answer 1

• Uraemia

- Malaise and fatigue

Question 2

What eGFR is usually the cutoff at which patients need to start RRT (renal replacement therapy)?

Answer 2

eGFR < 10 mL/min

Question 3

What are the types of RRT?

Answer 3

• Renal transplant
• Haemodialysis
• Peritoneal dialysis
• Conservative kidney management

Question 4

What is dialysis?

Answer 4

Dialysis is the process of altering the solute composition of solution A by exposing it to solution B, across a semipermeable membrane

Question 5

What are the different types of access points in the body of the patient made for haemodialysis?

Answer 5

Permanent:

• Arteriovenous fistula
• Arteriovenous graft

Temporary:
- Tunnelled venous catheter

Question 6

What solutes does the dialysis machine want to create net movement of?

Answer 6

• HCO3 back into the blood (some excreted)
• Creatinine excreted
• Urea excreted

Question 7

What does an AV fistula do? If you can’t do a fistula, whats option 2?

Answer 7

• AV fistula: artificial anastomosis between artery and a vein in arm, creates higher pressure in the vein which allows for wall thickening that eventually supports repeated needle punctures in dialysis
• AV graft: same thing but use a graft to connect the two vessels, more prone to clots

Question 8

What dietary restrictions are often given to dialysis patients?

Answer 8

• Fluid restrictions (based on residual urine output)

- K, Na & PO4 restrictions

Question 9

Describe haemodialysis?

Answer 9

• Make an AV fistula
• Couple of syringes into arterial and venous supply
• Blood flows through into dialyser, mixes with dialysate across semi permeable membrane
• Filtered blood goes back on in to blood supply

Question 10

Describe peritoneal dialysis?

Answer 10

A balanced dialysis solution is instilled into the peritoneal cavity via a cuffed catheter, using the peritoneal membrane as a dialysis membrane

• After a dwell time the fluid is drained and fresh solution is instilled in

Question 11

What are the types of peritoneal dialysis?

Answer 11

• Continuous ambulatory peritoneal dialysis (CAPD)
• Automated peritoneal dialysis (APD)
• Hybrids

Question 12

What is the most common osmotic agent for ultrafiltration of fluid in peritoneal dialysis?

Answer 12

• Glucose

Question 13

What are some possible complications of peritoneal dialysis?

Answer 13

• Exit site infection
• Peritonitis
• Ultrafiltration failure
• Abdominal wall hernia

Question 14

What are some indications for dialysis in end stage renal disease?

Answer 14

• GFR 5-10mL/min, advanced uraemia
• Severe acidosis (HCO3 < 10mmol/L)
• Treatment resistant hyperkalaemia (K > 6.5mmol/L)
• Treatment resistant fluid overload

Question 15

Which type of dialysis exerts greater fluid restrictions on patients, haemodialysis or peritoneal dialysis?

Answer 15

• Haemodialysis

Usually restricted to 500-800 mL/24h

Question 16

What are some drugs that patients on dialysis may be in need of?

Answer 16

• Erythropoetin injections
• IV iron supplements
• Activated vitamin D
• Phosphate binders with meals

Question 17

What are some complications of haemodialysis?

Answer 17

Intra-dialytic hypotension and cramps
Arrythmias
Clotting of vascular access
Heparin related problems

Question 18

When might a patient consider conservative kidney management over dialysis?

Answer 18

• When old and frail w other co-morbidities

- Dialysis can be quite draining