When a patient’s kidney function declines to the point where the need for dialysis seems likely, it is important to start planning ahead. One of the first steps is the vein mapping test. Hemodialysis requires a way to connect a person’s blood stream to the dialysis machine. The blood flow through the dialysis machine is so high that the typical vein would not work for this. There are only 3 ways that adequate blood flow for this kind of dialysis can be achieved.
1. The arteriovenous fistula (AVF) is the most favored option. A surgeon creates an AVF by connecting one of the arteries in the arm to a nearby vein. With time, the vein enlarges and thickens to the point where needles can be placed during the dialysis treatment to allow for cleaning of the blood, and the vein can handle the high blood flow needed. There are only a few sites in each arm where an AVF can be placed. Not everyone has veins that are adequate for use with creation of an AVF. The vein mapping test determines if a fistula can be placed and can roughly tell how long it would take until the fistula can be used. Fistulas generally take several months to develop.
2. For those patient approaching dialysis who cannot have an AVF, the next best option is The AV graft (AVG). This involves placing an artificial blood vessel (or graft) under the skin that connects an artery to a vein. Needles for dialysis are placed through the skin into the graft for dialysis treatments. Grafts can be placed in the arms, thighs and occasionally the chest wall and are possible in many patients who cannot have AVFs. AVGs are typically ready for use in 2-3 weeks.
3. If a patient develops kidney failure suddenly and does not have time to plan ahead, options for hemodialysis are limited to one of several different types of dialysis catheters. Catheters can be used immediately after they are placed and are commonly used in hospitals when patients develop acute or sudden kidney failure. A special type of catheter is designed for outpatient use. These catheters (sometimes called permcaths even though they are by no means permanent) are placed in a vein in the neck or groin and tunneled a short distance under the skin to help prevent bleeding, infection or the catheter accidentally falling out. Catheters are ready for immediate dialysis, but have several disadvantages. Disadvantages include the possibility of damaging the veins in the shoulder or chest as well as an increased risk of severe blood stream infection. They should be used only as a temporary measure.
Vein mapping is your doctor’s best way to minimize the chance that a dialysis catheter will be needed and maximize the chance that a fistula will be ready to use by the time dialysis is required. This has been shown to help patients avoid complications and live longer as they transition to needing hemodialysis.
Vein mapping is performed by a nephrologist at the Azura Surgery Center on Columbiana Road in Homewood, AL. When you arrive for the test, you will meet your nurse who will prepare you for the mapping. The nephrologist will explain the test and discuss among other things which arm to study. Typically the non-dominant arm is chosen first, but the presence of past surgeries or certain types of pacemakers may alter this. An IV is placed in a vein in the selected arm and the patient is taken to the procedure room. A small amount of x-ray dye is used to take x-ray pictures of the veins in the arm and shoulder. An ultrasound is then used to check the flow in arteries in the arm as well as take measurements of potential target fistula veins. The actual test takes around 5 minutes. A report is generated and the results are discussed with the patient. An appointment with the appropriate surgeon can be made at this point or delayed until after the patient has a chance to see their nephrologist in clinic.
Which access is best varies by patient. Your nephrologist will recommend 1-2 options to you and help you find the best one for your particular situation.
AVF - Advantages
AVF - Disadvantages
AVG - Advantages
AVG - Disadvantages
Dialysis Catheter - Advantages
Dialysis Catheter - Disadvantages
Your kidneys are bean-shaped organs, each about the size of your fist. They are located near the middle of your back, just below the rib cage. The kidneys are sophisticated trash collectors. Every day, your kidneys process about 200 quarts of blood to sift out about 2 quarts of waste products and extra water. The waste and extra water become urine, which flows to your bladder through tubes called ureters. Your bladder stores urine until you go to the bathroom.
The wastes in your blood come from the normal breakdown of active muscle and from the food you eat. Your body uses the food for energy and self-repair. After your body has taken what it needs from the food, waste is sent to the blood. If your kidneys did not remove these wastes, the wastes would build up in the blood and damage your body.
For more information, please download this extensively detailed PDF.
The kidneys are the master chemists of the body. They filter and remove waste products from the blood, remove extra water from the body, adjust levels of minerals and chemicals in your body and produce hormones that help control your blood pressure and help make red blood cells.
There are a number of ways you can protect your kidneys and slow the progression of CKD.
Good blood pressure control, diet modifications, smoking cessation and if you are a diabetic, keeping your blood sugar in a safe range are all ways you can positively affect your kidney function. In addition, keep informed about your test results, ask questions, and be involved in your treatment plan.
You are the most important member of your health care team.
A nephrologist is a doctor who treats patients with kidney problems and related hypertension or high blood pressure. Once you have been diagnosed with kidney disease, early referral to a nephrologist is important in preserving and protecting your kidney function. As a specialist in kidney disease, your nephrologist has the knowledge and skill to work with you in developing a plan of care specific to your needs.
One way to preserve your kidney function is to modify your diet. Proper nutrition can reduce the workload of the kidneys and preserve or delay further progression of your kidney disease. A renal dietitian can help you make good choices with the foods you normally eat and make suggestions on foods to add and foods to moderate in your diet. The dietitian is an important part of your healthcare team and can assist you in living well with chronic kidney disease.
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Diabetes is the most common cause of chronic kidney disease (CKD) in the United States. High blood sugar levels can damage the blood vessels and affect the filtering ability of the kidney. Controlling your blood sugar can help slow the progress of your kidney disease.
High blood pressure damages the blood vessels and reduces blood supply to the kidney. High blood pressure can cause kidney problems and kidney problems can cause high blood pressure. Uncontrolled high blood pressure can cause a decrease in kidney function and irreversible kidney damage.
Anemia is a decrease in red blood cells. Red blood cells carry oxygen throughout the body and a decrease in red blood cells can result in fatigue, shortness of breath, depression, poor appetite and heart disease.
The kidneys make a hormone called erythropoietin which helps form red blood cells. With CKD there is a decrease in the production of this hormone and thus a decrease in red blood cells. The treatment for anemia related to CKD is injections with the man-made form of the hormone erythropoietin and with iron pills or iron infusions (intravenous iron).
CKD is chronic kidney disease. CKD is defined as a decreased level of kidney function or the evidence of kidney damage for greater than three months. Individuals at risk for developing kidney disease are those with diabetes, high blood pressure or a family history of kidney disease.
Once CKD is diagnosed it is important to determine the level of kidney function. The National Kidney Foundation has identified 5 stages of chronic kidney disease. Each stage represents a level of kidney function as defined by a creatinine clearance.
The 5 stages are:
Common medications to avoid are NSAIDS (anti-inflammatory medications), enemas and laxatives — unless ordered by the nephrologists, any “cure-all” remedies and various food supplements, herbal medicines and vitamins. It is a good idea to check with your nephrologist prior to starting any new over the counter or prescription medications.
Blood Tests – Serum creatinine, Electrolytes, & BUN
Urine Tests – Microalbumin, Glomerular Filtration Rate (GFR)
Imaging Tests – A renal ultrasound may be recommended to assess the size, shape and anatomy of your kidney. In addition, a CT scan, MRI or MRA may be recommended to determine possible reasons for your kidney disease.
Kidney Biopsy – A kidney biopsy is a test where a small piece of kidney tissue is removed by a needle. The tissue is examined under a microscope to determine the cause of kidney disease.
Hemodialysis, peritoneal dialysis and kidney transplant are all treatment options. Kidney transplantation surgically places a healthy kidney from another person into your body. The donated kidney does the work that your failed kidneys used to do. One additional option is to refuse or withdraw from treatment.
For many people dialysis and transplantation extend and improve quality of life. For others these treatment options may seem a burden and only to prolong suffering. You have the right to refuse or withdraw dialysis if you feel there is no hope of improving your quality of life or a life with dignity and meaning.
Dialysis is a process that cleans and filters your blood. There are three types of dialysis, in-center hemodialysis, home hemodialysis and home peritoneal dialysis.
In-Center Hemodialysis – Hemodialysis cleans your blood using a machine with a special filter called a dialyzer. During a hemodialysis treatment blood travels from your body through tubes to the dialyzer which filters out wastes and extra water. The cleaned blood flows through another set of tubes back into your body.
Home Hemodialysis – Home hemodialysis uses the same process as in-center hemodialysis, except that you and a care partner are trained to do your treatment at home.
Home Peritoneal Dialysis – Peritoneal dialysis removes wastes and extra water from your body using the lining of your abdomen (peritoneum) to filter your blood. A special solution travels through a soft tube into your abdomen. The solution draws wastes and extra water from tiny blood vessels in your peritoneum back into the solution which is then drained from your abdomen through the soft tube. This is the most common type of home dialysis.
For hemodialysis it is necessary to create a vascular access or pathway to your blood. The access is usually created in your arm during a short surgery. One type of access is a fistula, another type of access is a graft. In some cases an external catheter may be inserted into a vein in your chest or neck. A catheter is usually temporary and replaced by a fistula or graft.
High blood pressure may be controlled with a combination of weight loss, exercise, changes in diet, stress reduction and smoking cessation. If these steps do not control your blood pressure then medications, often a combination of medications is recommended. Each type of blood pressure medication you take provides a different benefit for controlling your blood pressure and slowing the progression of kidney disease.
Existing patients may use the Patient Portal.