Dialysis Basics & Treatment Options
The Devastating Effects of Kidney Failure
Kidney failure is a serious health risk, and can result in a wide range of medical complications, up to and including death.
As your kidney function declines, your body fills with extra water, salt and waste products. Your hands and feet can start to swell. You begin to feel tired and weak because your body needs clean blood to function properly. It is important to seek medical attention immediately with kidney failure, and begin treatments in order to restore function.
Treating Kidney Failure with Dialysis
Kidney failure is a serious health concern that needs to be immediately treated with dialysis.
When your kidney function dips to about 15 percent, hemodialysis or peritoneal dialysis become necessary. Your alternate option would be a kidney transplant, but finding a match can often take time.
Hemodialysis removes waste products and extra fluid from the blood by using a special filter called a dialyzer in conjunction with a hemodialysis machine (Figure 1). The hemodialysis machine moves your blood through the dialyzer. A pump on the hemodialysis machine draws your blood, a small volume at a time, through a needle in your dialysis access into a tube. The tube moves your blood through the dialyzer.
Figure 1 Hemodialysis Machine
The dialyzer (Figure 2) has two compartments; the blood compartment and the dialysate fluid compartment. The dialysate fluid is the fluid that cleans your blood. Your blood enters the dialyzer from the top and flows inside of the membranes. The membranes have tiny holes (pores) that are only big enough to remove the waste products and toxins. The important parts of your blood, like your red blood cells and protein, stay inside the membrane and are returned to your body along with your clean blood. At the same time your blood is entering the dialyzer from the top, the clean dialysate fluid enters the dialyzer from the bottom, surrounding each membrane that contains your blood. The blood and dialysate fluid move in opposite directions and do not mix. The dialysate fluid removes the wastes from your blood as it travels upward and outside of the membrane. When the dialysate fluid with the wastes reaches the top of the dialyzer (artificial kidney), the wastes and excess fluid leave the dialyzer and are sent to the drain. This is a continuous process during the treatment.
Figure 2 Dialyzer
In order to perform any type of hemodialysis treatment, a vascular access is required so there is a convenient entryway into your bloodstream. Placement of a vascular access requires a minor surgical procedure. Further discussion regarding vascular access is discussed in the "Dialysis Access" tab.
Hemodialysis replaces part of your kidney function but you will also need dietary changes, medicines and limits on water and other fluids you drink and get from food. Your care team will assess your specific needs and medical conditions and create an individualized treatment plan just for you.
Hemodialysis treatments are usually 3 to 5 hours long, depending on a patient's specific medical needs and how frequently they will dialyze. Many patients dialyze 3 times a week but some may dialyze as much as 6 times per week. Patients can get hemodialysis at an outpatient dialysis center, referred to as "incenter hemodialysis" or patients can choose to dialyze at home, referred to as "home hemodialysis"
Incenter hemodialysis is performed at a dialysis facility and is the most common form of dialysis treatment in the United States. Most dialysis facilities are set up as an open floor plan with recliners next to the dialysis machines. Hemodialysis treatments are usually performed times a week.
Typically your dialysis treatment will require you to be weighed before and after each treatment. Your weight provides important information about how much fluid needs to be removed during treatment and how much fluid is actually removed during treatment. Specially trained nurses and dialysis technicians will briefly assess you before treatment to make sure you are medically stable for treatment. The staff will insert the needles into your dialysis access and complete the treatment for you. Nurses and technicians are always there with you and will monitor you throughout your treatment. After treatment staff will assess you again to make sure you are stable and safe to leave.
Patients receive medications and have routine lab work drawn during their treatments as indicated by their specific medical conditions and needs. Your nephrologist will come and see you during your treatment several times during a month. During dialysis you will probably also see your dietitian and social worker.
The dialysis facility schedules patient dialysis treatment according to the availability of openings in the facility. Patient schedules are usually Monday, Wednesday and Friday or Tuesday, Thursday and Saturday. Most facilities have two shifts per day and some also offer an evening shift for patients who work during the day. Every effort is made to schedule your treatment according to your specific needs. The hemodialysis center also provides patients with the opportunity to meet and talk with other dialysis patients and many patients enjoy this social aspect of incenter hemodialysis.
Home hemodialysis is a growing treatment option in which you and a trained partner can perform your hemodialysis treatments in the comfort of your own home and when it is convenient for you. Home hemodialysis requires that you and your partner (usually a family member or close friend) complete a training course. During training, you and your partner will learn how to do the treatments in the clinic while working with your training staff. The length of training will vary for each patient. Training is customized to your needs and to the type of equipment your dialysis provider uses for home hemodialysis.
The training program will teach you and your partner all the necessary skills to dialyze safely and effectively at home. You will learn how to troubleshoot problems and how to properly manage emergencies. You will also be taught how to order your supplies and maintain your equipment and water. The equipment and supplies are delivered directly to you. Support is available to you by phone 24 hours a day.
Home hemodialysis treatments allow for flexibility in the time of day you complete your treatment. Often home hemodialysis patients dialyze more frequently and the additional dialysis allows for better fluid management and removal of toxins and waste. Patients can also take their hemodialysis machine when traveling.
You will still need to travel to your clinic at least once a month for your care team to assess your condition and the effectiveness of your treatment. During your clinic visit you will have blood work drawn, may receive some medications and can have your questions and concerns addressed.
Nocturnal dialysis is a treatment option for patients who choose to dialyze at night. Instead of dialyzing during the day, patients receive their treatment over a time period of about eight hours while they sleep. The treatment is usually prescribed three times a week. Because nocturnal dialysis is performed over a longer period of time and at a slower blood flow rate, patients do not usually experience complications such as low blood pressure and muscle cramping. This option is currently available in selected areas and may be available as a home hemodialysis option. If you are interested in this option, consult with your physician.
Daily Hemodialysis (5-6 treatments/week)
If you and your nephrologist determine that daily hemodialysis is best for you, either incenter or at home, you may experience additional benefits. The additional time on dialysis provides patients with better fluid and waste removal which often results in patients feeling better. Patients can often have more liberalized diet and fluid intake. Some patients may even be able to decrease or discontinue some of their medication. The same benefits are also often achieved with nocturnal dialysis because of the additional dialysis time patients receive. Treatment length will vary based on patient needs and the specific technology used.
What are the Possible Risks of Hemodialysis?
- Blood loss
- Decrease of blood pressure which can lead to the loss of consciousness and access complications
- Allergic reaction to the dialyzer material
- Air entering the bloodstream (air embolism)
- Muscle cramping
- Pain, bruising, and swelling at the places where the needles are placed (infiltration)
- Clotting of the vascular access
In order to perform any type of hemodialysis treatment a vascular access is required. The vascular access is so important that it is sometimes referred to as your "lifeline". The access is the site on your body where blood is removed and returned during dialysis. The dialysis access provides a way for blood to flow from your body to the dialyzer for cleaning and then back to your body. To maximize the amount of blood cleansed during hemodialysis treatments, the vascular access should allow your blood to flow at the rate ordered by your doctor. Ideally, a vascular access should be placed weeks or months before you start dialysis. The early placement of the vascular access will allow sufficient time for the access to heal and mature. The three basic kinds of vascular access for hemodialysis are an arteriovenous (AV) fistula, an arteriovenous (AV) graft, and a venous catheter.
Arteriovenous or AV Fistula (Figure 3)
A surgeon creates an AV fistula by connecting an artery directly to a vein, usually in the wrist or forearm. It is preferred that the fistula be placed in the arm you use the least. Connecting the artery to the vein causes more blood to flow into the vein. An AV fistula requires advance planning because a fistula takes a while after surgery to develop--usually from two to six months. A properly formed fistula is less likely than other kinds of vascular accesses to form clots or become infected. Also, properly formed fistulas tend to last years longer than any other kind of vascular access.
Once the AV Fistula has been created and matures you will be able to feel the vibration or pulse of the blood flowing through your access. This feeling is called a thrill. Your healthcare professional will also listen for the blood flowing in your access with a stethoscope. The "whoosh" sound that is heard through the stethoscope is called a bruit (pronounced brew-ee). You will become familiar with how to check your access daily to make sure it is working properly. The high blood flow from the artery through the vein helps the access grow larger and stronger, making needle insertions for hemodialysis treatments easier. The fistula takes some time to develop. You will need to exercise the arm with the fistula to help it develop. For the surgery, you'll be given a local anesthetic. In most cases, the procedure can be performed on an outpatient basis. Although it is the preferred access, small veins or other conditions could make it difficult for some people to have a successful fistula. Your surgeon may order a test (vessel mapping) to check the size and quality of your veins and blood flow to determine the best access for you. These and other problems with vascular access can be corrected when determined in the early stages. Your healthcare team will monitor your access regularly to help you keep your access healthy and working properly.
Figure 3 AV Fistula
Arteriovenous AV Graft Figure 4
If you have small or weak veins that won't develop properly into a fistula, you can have a vascular access placed that connects an artery to a vein using a synthetic tube, or graft, implanted under the skin in your arm. The AV graft is usually a soft, man-made tube that connects to an artery on one end and to a vein on the other end, allowing blood to flow through it. The artificial graft material is used for needle placement for blood access during hemodialysis. A graft does not need as long to develop as a fistula does, so it can be used sooner after placement, often within two to four weeks. The thrill (vibration felt due to the high blood flow) can also be felt in a graft, and the bruit ("whooshing" noise) can be heard with a stethoscope if the graft is functioning properly. You will become familiar with how to check your access daily to make sure it is working properly. Compared with properly formed fistulas, grafts tend to have more problems with clotting and infection and need replacement sooner. However, a well-cared-for graft can last several years.
Figure 4: AV Graft
Catheters Figure 5
A catheter is a flexible, hollow tube inserted into a large vein in your neck, chest, or leg near the groin which allows the blood to flow into and out of your body. A catheter is most commonly used as a temporary dialysis access. There are several places on your body where a catheter can be placed. The most common are:
- Internal jugular catheter - inserted into the jugular vein on the side of the neck.
- Subclavian catheter - placed into the subclavian vein under the collar bone on the chest.
- Femoral catheter - placed in the large vein in the leg near the groin.
A catheter has two chambers to allow a two-way flow of blood. One chamber allows blood to flow out of the body to be cleaned and the other chamber allows cleaned blood to return to the body. Catheters contain an exit site where the catheter comes out of the skin. This is covered by bandages or other types of dressings. These dressings need to be changed and kept clean and dry at all times. Some catheters require stitches at the exit site where the catheter comes out of your skin to help hold the catheter in place. Some catheters tunnel under the skin and have a small bulged area near the exit site called a "cuff." The cuff remains under the skin and helps to hold the catheter in place and helps to prevent infection.
Figure 5: Dialysis Catheters
Catheters are not the ideal permanent access, but, if your kidney disease has progressed quickly or you are waiting for your permanent access to mature or heal, you may need to have a catheter placed as a temporary access. The type of catheter you have placed usually depends on how long you will need to have the catheter.
Catheters do not usually allow for a large volume of blood to flow to the dialyzer which can result in a less efficient treatment. Catheters can clot, become infected, and can cause narrowing of the veins (stenosis) in which they are placed. However, if you need to start hemodialysis immediately, a catheter will work for several weeks or months while your permanent access develops.
For some people, fistula or graft surgery is unsuccessful, and they will need to use a permanent catheter as their long-term access. Catheters that will be needed for more than about three weeks are designed to be tunneled under the skin to increase comfort and reduce complications. Even tunneled catheters are prone to infection. The catheter will have an exit site which is covered with a protective bandage. These bandages must be changed and kept dry at all times.
Peritoneal dialysis, or PD, is a daily treatment. PD is a procedure that removes wastes, chemicals and extra fluid from your body. This type of dialysis uses the thin, natural lining of your abdomen to filter your blood. The lining is called the peritoneal membrane. The peritoneal membrane surrounds the abdominal cavity, which contains your stomach, spleen, liver and intestines. The peritoneal membrane acts as the artificial kidney. It has many tiny holes, or pores, in it that can be used to filter waste products and other chemicals from your blood.
How does peritoneal dialysis work?
To prepare for PD, a surgeon places a permanent tube called a catheter into the lower abdomen to carry solution in and out of the abdomen. The solution is a germ-free mixture of minerals and sugar dissolved in water, called dialysate. You fill your abdomen with the dialysate through the catheter. This is done by connecting the dialysate to the catheter with special tubing. While the solution sits in your abdomen it soaks up wastes, chemicals and extra fluid from your blood. After several hours you will drain the "used" fluid out of your abdomen through the catheter and into an empty bag and dispose of the fluid. Your abdomen is then refilled with fresh dialysate and the cycle is repeated. Each cycle of draining used dialysate and refilling with fresh dialysate is called an exchange. The process goes on continuously so you always have dialysate in your abdomen soaking up wastes and extra fluid. The amount of time the dialysate solution remains in the abdomen for waste and fluid removal is called the dwell time. The amount of fluid, the dwell time and the number of exchanges per day are prescribed by your nephrologist. There are two types of peritoneal dialysis, continuous ambulatory peritoneal dialysis and continuous cycling peritoneal dialysis.
Figure 6: Peritoneal Dialysis
CAPD - Continuous Ambulatory Peritoneal Dialysis
In CAPD the patient fills the abdomen with a fresh bag of dialysate manually, using the force of gravity. After four to six hours of dwell time, the patient empties the solution containing wastes out of the abdomen and into the drain bag. The patient then repeats the cycle with a fresh bag of dialysate at least four times a day. Each exchange takes about 20-40 minutes. The patient can move around and complete normal activities during the dwell time (four to six hours). Many patients find CAPD attractive as a treatment because it allows patients more freedom and independence than most other treatment types. CAPD does not require a machine; the process uses gravity to fill and empty the abdomen. Exchanges can be done in any clean location which makes it very easy to be mobile and to travel.
CCPD - Continuous Cycling Peritoneal Dialysis
CCPD uses a machine called a cycler to fill and empty your abdomen with the dialysate solution while you are sleeping or in a resting position. The cycler fills the peritoneum with dialysate and is programmed to allow the fluid to remain in the abdomen for the prescribed dwell time. The machine then drains the used dialysate into an empty bag. This process is repeated three to five times during the night while you sleep and requires 8+ hours of sleep/rest position time. This method may offer freedom from daytime exchanges and, like CAPD, allows you to eat a less restrictive diet than those who choose hemodialysis.
Some patients may require or benefit from a mix of CAPD and CCPD. Your nephrologist will determine what is best for you.
Peritoneal Dialysis Training
If you choose peritoneal dialysis, you will come to the clinic daily for one to two weeks to learn how to care for yourself at home. You will be taught by a nurse who is experienced in training people to do their own dialysis. You will learn how to troubleshoot problems and how to properly manage emergencies. You will also be taught how to order your supplies and maintain your cycler. Support is available to you by phone 24 hours a day.
You will still need to travel to your clinic at least once at least once a month for your care team to assess your condition and the effectiveness of your treatment. During your clinic visit you will have blood work drawn, may receive some medications and can have your questions and concerns addressed.
Risks of Peritoneal Dialysis
- Dislodged catheter
- Elevated blood glucose
Transplantation is an alternative to hemodialysis or peritoneal dialysis. It is a treatment but not a cure for kidney disease.
The transplantation process has many steps. First, talk with your doctor because transplantation isn't for everyone. You could have a condition that would make transplantation dangerous or unlikely to succeed.
The transplant procedure involves removing a normal functioning kidney from one individual and placing it into someone whose kidneys have failed. If the transplant is successful, the new kidney takes over and you no longer need dialysis. The kidney transplantation involves receiving a healthy kidney from either a living donor or from an individual who has died (deceased donor).
Figure 7: Transplantation
The kidney that you receive must be a good match for your body. The more the new kidney is like you, the less likely your immune system is to reject it. Your immune system protects you from disease by attacking anything that is not recognized as a normal part of your body. Your immune system will attack a kidney that appears to be "foreign." You will take special medications to help trick your immune system so it does not reject the transplanted kidney.
The new kidney is placed in the abdominal cavity (Figure 7) and sewn to the recipient's vein, artery, and bladder by a team of highly specialized transplant surgeons. The transplanted kidney may start working right away or it may take up to a few weeks to make urine. Unless your own kidneys are causing infection or high blood pressure, they are left in place. The average hospital stay is five to ten days after transplant.
What are the advantages and challenges of living donation?
One advantage of receiving a kidney transplant from a living donor is that the average long-term success rates tend to be significantly higher than transplants from nonliving donors. Another advantage is that the operation can be scheduled to suit your needs because it is not necessary to wait the usual two to four years or more for a kidney to become available from a deceased donor. One challenge is that a healthy donor must undergo an operation to remove the kidney to be transplanted into you, the recipient.