The function of the kidneys is to filter blood and remove toxic waste products. The kidneys excrete the toxic waste products as urine. When the kidneys fail, toxic waste products accumulate in the blood and can cause death. Dialysis is a method of treating kidney failure. During dialysis, the blood is filtered by a dialysis machine which removes the toxic waste products.
There are two types of dialysis: hemodialysis and peritoneal dialysis.
Hemodialysis
The more commonly used method is hemodialysis or “blood dialysis”. Hemodialysis is a process where a machine takes out the blood, filters it and removes the waste products, and then returns the “clean” blood to the body’s circulation.
Hemodialysis is performed at a dialysis center, often three times a week, for three to five or more hours. Vascular access is necessary for hemodialysis, this can be a fistula or a graft, which is created by the vascular surgeon on one arm. The advantage of hemodialysis is that trained professionals are available at dialysis centers to do the hemodialysis.
However, hemodialysis is not without complications. One might feel giddy or unwell after a dialysis session because of changes in blood volume as blood is taken out of the body and then replaced. There may be problems with the vascular fistula or graft, such as blockage or infection or bleeding after dialysis.
Peritoneal dialysis
Peritoneal dialysis or “water dialysis” uses the lining of the abdomen, called the peritoneal membrane, to filter the blood. Again surgery is required; this time to place a Tenchkoff catheter into the abdomen. During peritoneal dialysis, a tube is used to fill the abdomen with the dialysis solution, and after the dialysis, the tube is used to drain the dialysis solution from the abdomen.
Peritoneal dialysis is usually performed four times a day for 4 to 6 hours each time. Peritoneal dialysis can also be arranged to be done at night while sleeping, so that one can function normally during the day and receive dialysis at night.
The advantages of peritoneal dialysis are that it does not require vascular access and can be done in one’s own home. Because peritoneal dialysis is performed more often than hemodialysis, it is thought to be more efficient.
The disadvantage of peritoneal dialysis is that one can get peritonitis, which is an infection of the peritoneal membrane. Peritonitis is a real risk in peritoneal dialysis, and can easily occur if one is not careful during the filling and draining procedure and introduces bacteria via the tube into the abdomen. Therefore peritoneal dialysis is not offered to patients who are not motivated and have poor self care and no caregiver.
In order to choose between hemodialysis and peritoneal dialysis, one must understand the advantages and disadvantages of each technique and discuss with the renal physician which method of dialysis is best suited to one’s needs.
