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‘Renal Replacement Therapy’: Your options

 

For patients with chronic kidney disease, there is a chance your kidney may reach the fifth stage and cease to function. However, with today’s medical techniques, we can sustain your condition and get you back to your regular lifestyle as normally as possible.

 

What is ‘Renal Replacement Therapy’?

Renal replacement therapy is treatment option in chronic kidney disease stage 5 or ‘End stage kidney disease’. In this stage, the kidney is unable to remove byproducts and excessive fluid accumulated in the body. Hence, renal replacement therapy is essential to the patient.

Types of Renal Replacement Therapy

There are mainly three types of renal replacement therapies which your doctor can help choosing the best option.

Peritoneal dialysis

Peritoneal dialysis uses peritoneal membrane lining in abdominal cavity as the dialyzer to remove wastes and excessive fluid built up in your body by diffusing them along concentration gradient between glucose dialysate fluid and blood in peritoneal capillary. The glucose dialysate is drained into abdominal cavity by the Tenchkoff catheter (abdominal catheter) placed in the area for 4-6 hours. The break in period is usually two weeks for the healing of catheter wound to be used.

 

Three types of peritoneal dialysis

1. Continuous Ambulatory Peritoneal Dialysis (CAPD)

The dialysate is drained into abdominal cavity for 30-40 minutes, left for 4-6 hours (dwell time) and then drained out for another 30-40 minutes. This process is called One Exchange. At least four exchanges can be done during day while the the dialysate can be left in the abdominal cavity during night.

2. Continuous Cycler-assisted Peritoneal Dialysis (CCPD)

The dialysate is exchanged at night by a cycler machine, then left in your abdominal cavity during your day. 

3. Combination of CAPD and CCPD

The objective of the combination between CAPD and CCPD is to increase the efficacy of removing wastes and excessive fluid in case of overweight patients or poor peritoneal membrane function. Nighttime cycler exchange in CAPD patients is increased, as well as daytime cycler exchange in CCPD patients.

Hemodialysis and vascular access type comparison

Hemodialysis is another method of renal replacement therapy that clean up your blood by dialyzer which function as artificial kidney. Your blood is removed from your body to a dialysis machine through vascular access. Then, it will be cleaned before returning to your body through vascular access. The dialysis session takes 3-5 hours and the dialysis schedules are three times a week. Vascular access preparation is crucial before the process.

 

 

Two types of vascular access

1. Temporary vascular access (double lumen catheter)

Double lumen catheter is a temporary vascular access for acute hemodialysis that has not enough time to prepare for permanent vascular access. The double lumen catheter will be ready to use once it is inserted into central vein (internal jugular vein, subclavian vein or femoral vein)

Pros

1. Ready to use after insertion

2. No needles are needed to connect to machine

Cons

1. Most prone to infection

2. May not have enough blood flow for dialysis

3. More likely to develop blood clot and become blocked

4. Can cause narrowing of major vessel

You need to wear a protective cover for your catheter to take a shower

5. You need to wear a protective cover for your catheter to take a shower

 

 

2. Permanent vascular access

2.1 Arteriovenous fistula (AVF)

AVF is a permanent vascular connection of artery and vein in your forearm created by vascular surgeon. This vascular connection increase blood flow in the vein, then deliver it back to your body.

Pros Cons
1. Not prone to infection  1. Needs to mature one to four months  before it can be used
2. Excellent blood flow once it is ready to use 2.  Needles are inserted to connect to thedialysis machine
3. Less likely to develop blood clots and become blocked      
4. You can take shower once the access heals   
5. Last longer  

 

2.2 Arteriovenous graft (AVG)

AVG is a permanent vascular access that requires a connecting tube between artery and vein in your forearm created by vascular surgeon.

Pros   Cons
1. Excellent blood flow once it is ready to use     1.   More prone to infection than AVF
2. You can take shower once the access heals  2.   More likely to develop blood clot and become blocked than AVF
   3.   Needs at least two weeks before it can be used
   4.   Needles are inserted to connect to the dialysis machine
   5.   Lasts less time than AVF

Kidney transplantation

Kidney transplantation is the best renal replacement therapy requiring surgery operation. This type of renal replacement therapy needs one transplanted kidney from deceased donor (brain-dead donor) or living donor (living relatives or living non- relative donor such as a spouse) to connect with your blood vessels and urinary bladder. Kidney function will start working from immediately to several weeks.

The advantages of a kidney transplantation from a living donor are a) eliminate waiting time in the transplant list, and b) the transplantation can be done when you and the donor are best ready. However, there are three factors for evaluating risk of transplanted kidney rejection.

  • Blood group
  • Human Leukocyte Antigens (HLA), a surface antigen which there are two alleles on each HLA-A, HLA-B, and HLA-DR
  • Cross-matching antigens Doctor needs to take the patient’s blood and the donor’s blood for testing. If cross-matching reaction is negative, the kidney transplantation will be performed.

This surgery operation takes 3-4 hours, and the patient has to stay in hospital for one week in case of no complication. The patient also needs to take immunosuppressive medications for preventing transplanted kidney rejection, and close follow-up with the doctor to evaluate kidney function.

Renal Replacement Therapy type comparison

 

Peritoneal dialysis

 

Hemodialysis

 

Kidney transplantation

CAPD

CCPD

Preserve residual renal function

Loss of residual renal function

The new kidney may start working right away or take up to few weeks

You can do it at time you choose

You can do it at night while you sleep

Treatments are scheduled by the center

Deceased donor: you may wait several years for suitable kidney

Living donor: you can schedule the operation when you’re both ready

4-6 exchanges a day

3-5 exchanges a night with an additional exchange in the morning

3 hemodialysis sessions a week

1 transplant may not last a lifetime

You don’t need a machine

You need a cycling machine

You need hemodialysis machine

You need major surgery

Self -treatment

Trained professionals are with you at all time

Transplant operation take place in a hospital

You need several training sessions

You don’t need training session

 

You must limit sodium and calories

You must limit sodium, potassium, phosphate and fluid

You have fewer diet restrictions

You must eat more protein

You must eat balance of high protein

You must take immunosuppressive drugs every day as long as the transplant kidney functions

Peritonitis (serious abdominal infection) is the most common problem

Vascular access problems include infection, blockage from clotting and poor blood flow are common problems

Rejection of transplanted kidney, infection, cancer and side effect of immunosuppressive drugs are common problems