Dialysis machines do the work of the kidneys, filtering waste, extra fluid, and excess salt from the blood. At NYU Langone, doctors may recommend dialysis for adults who’ve been diagnosed with advanced kidney disease or kidney failure who opt not to have a kidney transplant because they are being treated for other conditions, such as cancer. Dialysis is also used for people awaiting a kidney transplant. NYU Langone doctors typically recommend dialysis for people with less than 10 percent of normal kidney function.
Though dialysis can extend life, it has side effects. These include pericarditis, which is an inflammation of the membrane that surrounds the heart, and low or high blood pressure. Dialysis can also lead to itching, sleep apnea, infection, muscle cramps, and amyloidosis, which is a buildup of proteins in the blood that are deposited on the joints and tendons.
Both kidney failure and dialysis can cause anemia, a deficiency in red blood cells. Other side effects may include weakened bones and hyperkalemia, which means you have high potassium levels. Your doctor monitors your health during dialysis and recommends any necessary treatment to address side effects.
There are two types of dialysis.
In hemodialysis, blood is pumped from the body through tubes called catheters into a dialysis machine, which filters waste before returning clean blood to the body.
Weeks to months before you begin hemodialysis, a surgeon creates an access area in the arm or neck that allows blood to travel through catheters to the machine. This access can be created in different ways. Doctors may make a fistula by joining an artery and vein in the arm. Or they may use a graft, in which a soft tube joins an artery and vein in the arm. Doctors may also opt for a catheter, in which a soft tube is implanted in a large vein, usually in the neck. These procedures are typically performed with regional anesthesia to numb the area above the collarbone and the arm.
To begin treatment, two needles attached to catheters are inserted into the arm or neck to reach the access area. Blood enters one tube and is sent to the dialysis machine for filtering, and then returns to the body through the second tube. A few ounces of blood are filtered at a time.
You may experience nausea or abdominal cramps during dialysis. Your doctor may adjust your treatment to help ease these symptoms. Your blood pressure and heart rate are monitored. Afterward, the needles are removed and the access area is covered with a bandage. Your blood is tested once a month to ensure that waste is being removed properly.
For most people, dialysis treatment lasts three to four hours and occurs three times per week at an outpatient dialysis center. A typical schedule is Monday, Wednesday, Friday or Tuesday, Thursday, Saturday, at the same time of day.
Some people can be treated at home, using a portable hemodialysis machine, which is about the size of a suitcase. You and your caregiver are first trained to operate the machine.
In peritoneal dialysis, waste products are filtered from the blood inside the body. During this process, blood vessels in the membrane that surrounds your abdomen filter waste instead of the kidneys.
Two weeks before peritoneal dialysis begins, a general surgeon implants a catheter into the abdomen. During dialysis, a mixture of minerals and sugar is inserted into the catheter, helping to draw waste products into the abdominal cavity. The waste and dialysis mixture is then flushed out of the body via the catheter.
The process of filling and draining the abdomen is called an exchange. It is performed at home four times per day or overnight, while you sleep. Expert medical technicians teach you how to perform the procedure.
This type of dialysis may cause an infection at the location where the catheter enters the body or in the lining of the abdominal wall. Your doctor may prescribe antibiotics to help prevent infection.
It’s important to take proper care of the dialysis access area to prevent infections or blood clots. NYU Langone doctors recommend washing a fistula or graft with antibacterial soap once a day before treatment.
The catheter dressing—bandages that protect the area from infection—must be kept clean and dry. You should have an emergency dressing kit at home, so you can change the dressing between treatments, if needed.
Report any redness or warmth at the access site. This can be a sign of infection.