Diabetes and Renal (kidney) Dialysis

Dialysis must be done three times per week to both purify the blood and remove excess liquid.

Diabetes frequently causes complications in kidney function. These complications compromise the kidneys’ filtration system, requiring the use of one of two techniques to purify the blood:

•    hemodialysis
•    peritoneal dialysis

In both cases, the treatment disrupts people’s lives due to its frequency and the time required. Adapting to this new lifestyle is often difficult at the beginning of treatment, but most people can expect to benefit from an acceptable quality of life for many years.

Treatment choice

The choice between the two forms of treatment depends on several factors: medical, personal and social. Most people are free to choose their preferred method.

Hemodialysis requires adhering to a fixed schedule and living close to a dialysis centre. Even if you can receive treatment outside the centre, this option can make travelling complicated. However, this option offers more freedom between dialysis sessions.

Peritoneal dialysis requires self-care, but you only need a medical visit once a month. However, it is important to organize your schedule at home and at work to accommodate your treatments. Peritoneal dialysis demands a strict aseptic technique, because any contamination can cause intra-abdominal infections.

Hemodialysis

Hemodialysis (cleaning the blood) uses a dialyzer (artificial kidney) to purify the blood of people suffering from severe renal (kidney) failure.

The treatment

The treatment usually takes 4 hours. Dialysis must be done three times per week to both purify the blood and remove excess liquid. Hemodialysis treatment does not cure kidney disease; it acts as a substitute kidney. Therefore, it must continue indefinitely, unless you get a kidney transplant.

During treatment, you may eat, drink, read, watch TV or sleep. After dialysis, you will feel tired for a few hours.

The machine

The dialysis machine consists of a filter in which your blood circulates. The blood is mixed with a liquid called dialysate. The exchange between the two fluids (blood and dialysate) lets the blood eliminate certain substances (urea, creatinine, potassium, etc.) that were not filtered out by your impaired kidneys. A system of tubing returns the blood to your body.

The intervention

In order for your blood to move from the filter and then back to your body, a tubing system and access to your blood vessels are required. Most of the time, access is achieved by joining an artery to a vein in your arm to make a bigger vessel, called a fistula. This causes the pressure in the artery to be transmitted to the vein, which will then expand.

Thereafter, at each treatment, a needle is inserted in the vein to allow the blood to flow through the tubes into the filter. Another needle is inserted to allow the blood to flow back into your body. The needles are removed at the end of each treatment run.

Sometimes it is not possible to perform dialysis through a fistula. In that case, a catheter must be inserted into a large vein in your neck, which allows access to your blood. Since these catheters can become infected, it is preferable, whenever possible, to gain access via an arm.

Peritoneal dialysis

Peritoneal dialysis is another way to purify the blood. The principle behind this treatment method is to use the peritoneal membrane (the membrane surrounding the abdominal organs) as a filter. A small tube (catheter) is inserted into your abdomen, with one end extending outside the body.

The treatment

Through this tube, a liquid (usually 2 litres) resembling the dialysate used in hemodialysis is infused into the abdominal cavity, exposing the blood vessels in the peritoneum to the fluid. The peritoneum functions like the artificial membrane in a dialyzer. Excess water and waste (urea, creatinine, potassium, etc.) pass from the blood through the peritoneum into the dialysis fluid. Usually, the liquid is left in the abdomen for 4 hours and is then drained away using the catheter.

If you choose this form of treatment, you must do it four times per day, 7 days per week. You can remove the excess liquid by changing the concentrations of glucose in the liquid, which attracts the water by osmosis. It usually takes 30-45 minutes to drain the fluid and infuse two new litres.

Many diabetics who use this method of dialysis put their insulin in the dialysate so they no longer have to inject insulin subcutaneously. There are other forms of peritoneal dialysis that are done overnight, for 10 to 12 hours, but they require more complex equipment.

A specialized dialysis support team

A support team consisting of a nephrologist, dietitian, nurse, pharmacist and social worker can advise and support you in the choice of treatment to replace your kidney function.

These health care professionals will help you treat your kidney disease and slow the progression of complications from kidney failure.

Research and text: Diabetes Québec Team of Health Care Professionals, June 2014

Adapted from: Houde M., M.D., Nephrologist, Hôpital Maisonneuve-Rosemont, “Diabète and dialyse rénale,” Plein Soleil, (Autumn 2000), Diabetes Québec