Dialysis is the artificial process of eliminating waste (diffusion) and unwanted water (ultrafiltration) from the blood. 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 their fluid intake and diet. They will also need medication.
A significant number of patients on dialysis can go to work and lead normal lives. It is possible to go away on vacation as long as dialysis treatment is possible at their destination. Some doctors advise dialysis three times a week right from inception and some others advise twice a week initially followed by three times a week as per patient’s condition. One must remember that water intake is limited as per Doctor’s advice so it is better to have a measured water bottle to consume water as recommended.
How dialysis cleanses the blood
Dialysis cleanses the blood by passing it through a filter. In peritoneal dialysis (PD), the filter is the lining of abdomen (peritoneum). In hemodialysis, the filter is made of plastic, on one side is blood and on the other side is a fluid called dialysate Wastes and fluid in the blood passes through the filter into the dialysate. For PD, a dialysate is put into the patient’s peritoneum through a catheter (tube). The peritoneum has lots of small blood vessels. In a few hours, wastes and extra fluid move through the blood vessels and into the dialysate. The used dialysate is drained out through the catheter and thrown away. For hemodialysis, two needles are put into an access made in the wrist known as AV Fistula. One needle connects to a tube that brings the patient’s blood to a blood pump. The pump pushes blood through a filter called a dialyzer (artificial kidney). Inside the dialyzer are millions of hollow fibers. Each fiber has tiny holes in its walls. The toxic blood flows through the inside of the fibers and dialysate bathes the outside. Wastes and fluid go through the holes and into the dialysate. The toxins and wastes are removed and clean blood comes back through the AV Fistula access through the other needle. It takes a three to four hours for entire blood to be cleaned. The used dialysate is thrown away.
There are two types of dialysis-hemodialysis and peritoneal dialysis.
In hemodialysis, blood is pumped out of the patient’s body to an artificial kidney machine, and returned to back to the body by tubes connected to the machine. In peritoneal dialysis, the inside lining of the patient’s own belly acts as a natural filter. Wastes are taken out by means of a cleansing fluid called dialysate, which is washed in and out of the belly in cycles.
The doctor shall decide whether a patient should go for hemodialysis or peritoneal dialysis.
Planned Dialysis-AV Fistula
AV Fistula is created in the dominant arm of the patient. This AV Fistula site is where the blood can flow in and out of the body during the dialysis treatments. This is called dialysis access. Preparation for hemodialysis may begin six months or more, in advance of your first treatment. This time is needed to have a dialysis access placed in the arm by a vascular surgeon. The surgical access takes time to heal or mature, before it can be used. In some cases, the surgeon will plan for a two stage surgical procedure.
It is suggested that when AV Fistula operation is done and the site has matured (ghaa shukiye jawar pore), the patient should use a soft ball and press it as many times possible during the (may be upto 500 to 1000 times). This bulges the veins of the arm. When dialysis technicians insert needles to perform dialysis, the bulged veins enable easier insertion of needles.
Three types of accesses:
Arteriovenous Fistula (AVF). A surgically created connection between an artery and a vein, usually in your non dominant arm. This is the preferred type of access because of effectiveness and safety. However it may take several months for the fistula to form or mature.
Arteriovenous Graft (AVG). If your blood vessels are too small or not available, then the surgeon may use a synthetic material, a graft, to connect your artery to vein. A graft access can be used within a week or two, but is more prone to infection and clotting. In general, a graft access will not last as long as a fistula.
Central Venous Catheter (CVC). This is usually used if you need emergency hemodialysis. It is also used as a temporary access when AVF or AVG is not yet available. It is a synthetic tube that is inserted into a large neck vein, and protruded from below the collarbone. It may also be placed in the groin. The catheter is also prone to infection and blockages.