Dialysis is a treatment that performs the functions of natural kidneys when the they fail
(kidney failure)
. Most patients begin dialysis when their kidneys have lost 85%-90% of their ability to function, and will continue dialysis for the rest of their lives (or until they receive a kidney transplant). This is called
end-stage renal disease (ESRD)
.
ESRD may be caused by a variety of conditions that can impair kidney function, including diabetes,
kidney cancer
, drug use,
high blood pressure
, or other kidney problems. Dialysis is not a cure for ESRD, but helps you feel better and live longer.
The purpose of dialysis is to help keep the body's chemicals in balance, which the kidneys do when they are healthy. The main functions of dialysis are to:
Remove waste and excess fluid from the blood to prevent build-up
Control blood pressure
Keep a safe level of chemicals in the body, such as potassium, sodium, and chloride
Dialysis may also be done to quickly remove toxins from the bloodstream, in cases of poisoning or drug overdose.
Risk Factors for Complications During the Procedure
Topical anesthetic (a pain numbing medicine) is applied to the arm for needle insertion
Heparin (a medication that prevents blood clotting) is given
Peritoneal Dialysis
Before the first treatment, the physician places a small, soft tube (approximately 24 inches long) in the abdomen, which remains there permanently. A portion of the tube remains outside the body for use in the peritoneal dialysis process. It is important to keep this access clean and dry to prevent infection.
Anesthesia
For hemodialysis, topical anesthetic.
Description of the Procedure
Hemodialysis
An artificial kidney machine, called a dialyzer, filters the blood, and returns the cleaned blood to your body. You are connected to the dialyzer via tubes that are inserted into a vein in your arm, leg, or occasionally, neck. If hemodialysis is being performed as a temporary measure, then the catheter is likely to be inserted through the neck vein. If hemodialysis is going to be done regularly, then an access site called a fistula or shunt may be surgically created in one of your veins.
Fistulas may need as long as 2 to 3 months to fully heal or “mature” before they can be used on a regular basis. Occasionally a surgically created fistula may fail to heal properly, requiring either a revision or in some cases a completely new fistula to be created. For this reason, fistulas are never used in circumstances where the indications for dialysis are either emergent or temporary. Rather, they are typically created electively many months before dialysis is begun in cases of chronic renal failure where the need for dialysis is felt to be inevitable.
Hemodialysis is usually done at a dialysis center or hospital, by trained technicians or nurses, or may be done at home with assistance. Hemodialysis is usually done three times a week and each treatment lasts from two to four hours.
Instead of using a machine, this type of dialysis uses the abdominal lining, called the peritoneal membrane, to filter blood. A cleansing solution, called a dialysate, is infused through a tube inserted into your abdomen. Long-term peritoneal dialysis may require the surgical creation of a port in the abdomen through which this dialysate can be infused. Fluid, wastes, and chemicals pass from the tiny blood vessels in the peritoneal membrane into the dialysate, which is then drained after several hours. New dialysate can then be added to repeat the process.
There are three types of peritoneal dialysis:
Continuous ambulatory peritoneal dialysis (CAPD)—This is the most common type of peritoneal dialysis. A bag of dialysate is infused into the abdomen through a catheter, remains there for 3-6 hours, and is then drained. You then refill your abdomen with fresh solution through the catheter. This way your blood is always being cleaned. No machine is required, and the empty plastic bag may be hidden under clothing.
Continuous cyclical peritoneal dialysis (CCPD)—Fluid exchanges in this procedure are done by machine, usually at night while sleeping.
Intermittent peritoneal dialysis (IPD)—Uses the same type of machine as CCPD, but requires assistance and is usually done at a hospital or center. It often takes longer than CCPD.
Once blood pressure is stable, you may resume everyday activities.
How Long Will It Take?
The time needed for dialysis depends on a few factors:
How much kidney function remains
How much fluid weight gain has occurred since the last treatment
Amount of waste in the body
Body size
Level of minerals in your body such as sodium, potassium, and chloride
Dialysis method used
The approximate time and frequency of each method:
Type
Length of procedure
Frequency of procedure
Hemodialysis
2-4 hours
3 times/week
CAPD
3-6 hours, plus 30 minutes to drain
4 times/day
CCPD
9-12 hours
Every night
IPD
12 + hours
36-42 hours/week
Will It Hurt?
In general, dialysis procedures do not cause pain, and you will not feel the blood exchange. There may be some temporary discomfort with the insertion of the needle or tube.
Peritonitis
(infection of the peritoneum), which causes fever and stomach pain (peritoneal dialysis only)
Growth problems in children
Inflammation of the heart sac (pericarditis)
Neurologic problems
Disruption of calcium and phosphorus balance, resulting in weakened bones
Average Hospital Stay
None. Dialysis is typically done at an outpatient dialysis center or at home.
Postoperative Care
Once the hemodialysis procedure is completed and blood pressure is stabilized, you are free to continue daily activities. There are some special considerations, though:
Dietary Guidelines
Dialysis patients should follow certain dietary guidelines at all times to maintain health and optimize the dialysis process. Patients who have peritoneal dialysis may have slightly fewer dietary restrictions than hemodialysis patients, due to the more frequent peritoneal dialysis schedule. Your doctor and a dietitian will tailor the dietary guidelines to meet your specific needs. The factors you need to pay most attention to include protein, potassium, phosphorous, fluid, sodium, and total calories.
Medications
Your doctor may prescribe various types of medication. These include, but are not limited to
Blood pressure medications
Calcium supplements or multivitamins
Phosphorus binders—to lower phosphorus levels in the blood
Diuretics—to remove excess fluid
Stool softeners or laxatives—to prevent or treat constipation, which can be caused by decreased fluid intake
Iron supplements—to increase iron intake, which is important for production of red blood cells
Outcome
Dialysis helps maintain blood pressure, cleaning of the blood, and chemical and hormonal exchanges that are critical to survival.
Call Your Doctor If Any of the Following Occurs
Signs of infection, including fever and chills
Redness, swelling, warmth, increasing pain, excessive bleeding, or discharge at the catheter or tube insertion site
Blood or cloudiness in the peritoneal dialysis fluid
Nausea or vomiting
Abdominal pain
Dizziness or weakness
RESOURCES:
The Kidney Dialysis Foundation http://www.kdf.org
National Kidney Foundation http://www.kidney.org
National Kidney and Urologic Diseases Information Clearinghouse (NKUDIC) http://kidney.niddk.nih.gov
CANADIAN RESOURCES:
The Kidney Foundation of Canada: British Columbia Branch http://www.kidney.bc.ca/
The Kidney Foundation of Canada: Northern Alberta and the Territories Branch http://www.kidney.ab.ca
References:
National Diabetes Information Clearinghouse (NDIC) website. Available at:
http://diabetes.niddk.nih.gov/
.
National Kidney Foundation website. Available at:
http://www.kidney.org/
.
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
