When we are healthy our kidneys regulate our body levels of water and minerals, and remove waste. Dialysis does not correct the endocrine functions of failed kidneys – it only replaces some kidney functions, such as waste removal and fluid removal.
A study found that death rates for dialysis patients are 10%-15% lower for those whose homes are higher than 4,000 feet, compared to those who live at sea level.
Approximately 1,500 litres of blood are filtered by a healthy person’s kidneys each day. We could not live if waste products were not removed from our kidneys. People whose kidneys either do not work properly or not at all experience a buildup of waste in their blood. Without dialysis the amount of waste products in the blood would increase and eventually reach levels that would cause coma and death. Dialysis is also used to rapidly remove toxins or drugs from the blood. There are two main types of dialysis – haemodialysis and peritoneal dialysis
What is haemodialysis? The blood circulates outside the body of the patient – it goes through a machine that has special filters. The blood comes out of the patient through a catheter (a flexible tube) that is inserted into the vein. The filters do what the kidney’s do; they filter out the waste products from the blood. The filtered blood then returns to the patient via another catheter. The patient is, in effect, connected to a kind of artificial kidney.
What is peritoneal dialysis?A sterile (dialysate) solution rich in minerals and glucose is run through a tube into the peritoneal cavity, the abdominal body cavity around the intestine, where the peritoneal membrane acts as a semi-permeable membrane.
Although dialysis helps patients whose kidneys have failed, it is not as efficient as a normal kidney. Consequently, patients on dialysis need to be careful about what and how much they drink and eat. They will also need medications.
A significant number of patients on dialysis can work and lead normal lives. It is possible to go away on vacation as long as dialysis treatment is possible at their destination.
Women on dialysis will probably not be able to get pregnant. There will be a higher level of waste products in the body compared to a woman with normal kidneys – this interferes with fertility. Women who do become pregnant while on dialysis will probably need increased dialysis during the pregnancy. If a woman has a successful kidney transplant her fertility should return to normal. Dialysis has some effect on male fertility, but much less than on female fertility.