If you need Dialysis access the following information should be considered:
What are the two methods of dialysis?
Kidneys have significant reserve capacity and we can do well until their function decreases to about 10% of their original capacity. However, diabetes, hypertension, polycystic kidneys and other diseases can cause kidneys to fail. When this happens, toxins build up in your body which can cause death. Dialysis, which removes these toxins, is lifesaving but it is associated with problems.
There are two methods of dialysis, hemodialysis and peritoneal dialysis. Both work well and the choice between them is often personal preference.
- Hemodialysis, which is done in a dialysis unit three times a week, continuously removes blood, passing it through a machine to remove these toxins, and then returning your cleansed blood. The dialysis unit personnel need a way to remove and return blood and this is called your access. There are three kinds of access, catheters, fistulas and grafts. Catheters which usually go in the neck or shoulder are often used initially but they are bothersome and are always at risk for infection. The preferred access is a fistula which is created when a good sized vein near the wrist or elbow is connected to a nearby artery. Some of the blood is diverted from the artery to the vein. With this increased blood flowing in the vein, it becomes larger and vibrates. It is into this vein that the dialysis personnel place two needles; one to remove the blood and a second to return it. A good fistula sometimes lasts for years. If the veins are not usable, a special artificial tube can be attached to an artery, passed beneath the skin, and attached to a distant vein. This is called a graft. The dialysis personnel pass a needle through the skin into the underlying tube to remove and then return the blood. They too work well but are not as durable as fistulas. They can be repaired many times before they need to be replaced.
- Peritoneal dialysis, done daily in your home at night while you are sleeping, consists of placing a special fluid through a peritoneal dialysis catheter into your abdominal cavity (peritoneum) where the fluid slowly draws toxins from your body. Periodically, the dialysis machine automatically exchanges the old toxin containing fluid for fresh fluid while you sleep. This catheter, with one end in the peritoneal cavity passes through the abdominal wall exiting the skin below your belt line, is usually inconspicuous. This method works very well but always has the risk of infection. However, with training and continuous attention to detail, this risk is very low.
If you decide on hemodialysis?
Hemodialysis requires access to a continuous flow of blood. Hopefully, before dialysis is needed, there will be sufficient time to construct a fistula and allow it to mature or be ready to permit trouble free needle placement. This maturation often takes months. If there is not enough time, a temporary neck or shoulder catheter may need to be inserted until the fistula is ready. The catheter is removed after the fistula is mature and reliable. These operations are not dangerous or painful but they are inconvenient.
If you decide on peritoneal dialysis?
Inserting a peritoneal dialysis catheter is a small operation but the catheter cannot be used for two weeks while it heals. Hemodialysis would be necessary if dialysis is needed during this time. All abdominal operations interrupt peritoneal dialysis making hemodialysis necessary. Sometimes, even though you are on peritoneal dialysis, a backup fistula will be suggested. Infections affecting the catheter or the peritoneal cavity may prevent dialysis and require removal of the peritoneal dialysis catheter. If the peritoneal cavity recovers, the peritoneal dialysis catheter can be replaced but hemodialysis will be needed in the interim. Not everyone is a candidate for peritoneal dialysis but it is convenient and works very well.
What do I do when my access fails?
It would be ideal if every access lasted forever but unfortunately, nothing lasts that long! More than half of a dialysis patient’s admissions to the hospital are attributable to dialysis access problems. Catheters become infected or need repair, fistulas develop problems and grafts clot. Sometimes they are repaired in radiology, at other times surgical operations are needed. However, the vast majority of the procedures are more inconvenient than dangerous.
This is general information and we encourage a full and thorough discussion with you and your family about your dialysis access. Creating and maintaining your dialysis access is difficult work and your physicians are as distressed as you are when your access fails which they all do eventually. We are committed to maintaining your dialysis access.