In hemodialysis, a machine filters waste, salts and fluids from the blood when the kidneys are no longer healthy enough to do this job properly. Hemodialysis (he-moe-die-AL-uh-sis) is a way to treat advanced kidney failure and can help you lead an active life despite your kidney failure.
With hemodialysis, you will:
- Follow a rigorous treatment program.
- take medicine regularly
- Make changes to your diet
Hemodialysis is a serious responsibility, but you don't have to shoulder it alone. You will work closely with your healthcare team, including a kidney specialist and other professionals experienced in managing hemodialysis. You can do hemodialysis at home.
How the kidneys work
One of the important jobs of the kidneys is to clean the blood. As blood moves through the body, it picks up extra fluids, chemicals, and waste. The kidneys separate this material from the blood. It is eliminated from the body in the urine. If the kidneys cannot do this and the condition is not treated, serious health problems, with eventual loss of life, will result.
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Your doctor will help you determine when you should start hemodialysis based on several factors, including:
- general health
- kidney function
- signs and symptoms
- Quality of life
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You may notice signs and symptoms of kidney failure (uremia), such as nausea, vomiting, swelling, or fatigue. Your doctor uses your estimated glomerular filtration rate (eGFR) to measure your level of kidney function. Your eGFR is calculated using your blood creatinine test results, gender, age, and other factors. A normal value varies with age. This measure of your kidney function can help plan your treatment, including when to start hemodialysis.
Hemodialysis can help your body control your blood pressure and maintain the proper balance of fluids and various minerals, such as potassium and sodium, in your body. Hemodialysis usually starts long before your kidneys shut down to the point of causing life-threatening complications.
Common causes of kidney failure include:
- High blood pressure (hypertension)
- Kidney inflammation (glomerulonephritis)
- Kidney cysts (polycystic kidney disease)
- hereditary kidney diseases
- Prolonged use of nonsteroidal anti-inflammatory drugs or other medications that can damage the kidneys
However, your kidneys may suddenly stop working (acute kidney injury) after a serious illness, complicated surgery, heart attack, or other serious problem. Certain medications can also cause kidney damage.
Some people with severe, long-term (chronic) kidney failure may decide not to start dialysis and choose a different route. Instead, they may choose maximum medical therapy, also called maximum conservative treatment or palliative care. This therapy involves active management of complications of advanced chronic kidney disease, such as fluid overload, high blood pressure, and anemia, with a focus on supportive management of symptoms that affect quality of life.
Other people may be candidates for a preventative kidney transplant rather than starting dialysis. Ask your healthcare team for more information about your options. This is an individualized decision because the benefits of dialysis may vary depending on your specific health conditions.
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Most people who need hemodialysis have a variety of health problems. Hemodialysis prolongs the lives of many people, but the life expectancy of those who need it is still lower than that of the general population.
While hemodialysis treatment can be effective in replacing some of the lost kidney function, you may experience some of the related conditions listed below, although not everyone will experience all of these problems. Your dialysis team can help you deal with them.
- Low blood pressure (hypotension).A drop in blood pressure is a common side effect of hemodialysis. Low blood pressure may be accompanied by shortness of breath, abdominal cramps, muscle cramps, nausea or vomiting.
- Cãibras musculares.Although the cause is unclear, muscle cramps during hemodialysis are common. Sometimes cramping can be relieved by adjusting your hemodialysis prescription. Adjusting fluid and sodium intake between hemodialysis treatments can also help prevent symptoms during treatments.
- Itch.Many people on hemodialysis have itchy skin, which often gets worse during or shortly after the procedure.
- Sleeping problems.People on hemodialysis often have trouble sleeping, sometimes due to interruptions in breathing during sleep (sleep apnea) or leg pain, discomfort, or restlessness.
- Anemia.Not having enough red blood cells (anemia) is a common complication of kidney failure and hemodialysis. Kidney failure reduces the production of a hormone called erythropoietin (uh-rith-roe-POI-uh-tin), which stimulates the formation of red blood cells. Dietary restrictions, iron malabsorption, frequent blood tests, or removal of iron and vitamins through hemodialysis can also contribute to anemia.
- Bone diseases.If your damaged kidneys can no longer process vitamin D, which helps absorb calcium, your bones can become weak. In addition, overproduction of parathyroid hormone, a common complication of kidney failure, can release calcium from the bones. Hemodialysis can make these conditions worse by removing too much or too little calcium.
- High blood pressure (hypertension).If you eat too much salt or drink too much fluid, your high blood pressure is likely to get worse and lead to heart problems or stroke.
- Fluid overload.Because fluid is removed from your body during hemodialysis, drinking more fluid than recommended between hemodialysis treatments can cause life-threatening complications, such as heart failure or fluid buildup in your lungs (pulmonary oedema).
- Inflammation of the membrane surrounding the heart (pericarditis).Insufficient hemodialysis can cause inflammation of the membrane surrounding the heart, which can interfere with the heart's ability to pump blood to the rest of the body.
- High potassium levels (hyperkalemia) or low potassium levels (hypokalemia).Hemodialysis removes excess potassium, which is a mineral that is normally removed from the body by the kidneys. If too much or too little potassium is removed during dialysis, your heart may beat irregularly or stop.
- Access site complications.Potentially dangerous complications, such as infection, narrowing or dilation of the blood vessel wall (aneurysm), or blockage, can affect the quality of your hemodialysis. Follow your dialysis team's instructions on how to look for changes in your access site that might indicate a problem.
- Amilose.Dialysis-related amyloidosis (am-uh-loi-DO-sis) develops when proteins in the blood are deposited in joints and tendons, causing pain, stiffness, and fluid in the joints. The condition is more common in people who have had hemodialysis for several years.
- Depression.Mood swings are common in people with kidney failure. If you experience depression or anxiety after starting hemodialysis, talk to your healthcare team about effective treatment options.
how do you prepare
Preparation for hemodialysis begins several weeks or months before the first procedure. To facilitate access to the bloodstream, the surgeon will create a vascular access. Access provides a mechanism for a small amount of blood to be safely removed from your circulation and then returned to you for the hemodialysis process to work. Surgical access needs time to heal before starting hemodialysis treatments.
There are three types of access:
- Arteriovenous (AV) fistula.A surgically created AV fistula is a connection between an artery and a vein, usually in the arm that you use less often. This is the type of privileged access due to its efficiency and security.
- OF graft.If your blood vessels are too small to form an AV fistula, your surgeon can create a path between an artery and a vein using a flexible synthetic tube called a graft.
- Central venous catheter.If you need emergency hemodialysis, a plastic tube (catheter) may be inserted into a large vein in your neck. The catheter is temporary.
It is extremely important to take care of the access site to reduce the possibility of infection and other complications. Follow your healthcare team's instructions on how to care for your access site.
what can you expect
You can receive hemodialysis at a dialysis center, at home or in a hospital. The frequency of treatment varies, depending on your situation:
- Hemodialysis in center.Many people receive hemodialysis three times a week in sessions of 3 to 5 hours each.
- daily hemodialysis.This involves more frequent but shorter sessions, usually done at home, six to seven days a week, for about two hours at a time.
Simpler hemodialysis machines have made home hemodialysis less complicated, so with special training and someone to help you, you can do hemodialysis at home. You may even be able to do the procedure at night while you sleep.
There are dialysis centers located throughout the United States and a few other countries, so you can travel to many areas and still receive your hemodialysis on time. Your dialysis team can help you make appointments in other locations or you can contact your destination dialysis center directly. Plan ahead to ensure that space is available and that proper arrangements can be made.
During treatments, you sit or recline in a chair while blood flows through the dialyzer, a filter that acts like an artificial kidney to clean the blood. You can use the time to watch TV or a movie, read, take a nap or maybe chat with your "neighbours" downtown. If you receive hemodialysis at night, you will be able to sleep during the procedure.
- Preparation.Your weight, blood pressure, pulse, and temperature are checked. The skin over the access site, the point where blood leaves and re-enters the body during treatment, is cleaned.
- From.During hemodialysis, two needles are inserted into the arm through the access site and taped to secure them. Each needle is connected to a flexible plastic tube that connects to a dialyzer. Through a tube, the dialyzer filters your blood a few ounces at a time, allowing waste and extra fluid to pass from your blood into a cleaning fluid called a dialysate. The filtered blood returns to your body through the second tube.
- Symptoms.You may experience nausea and abdominal cramps as excess fluid is removed from your body, especially if you have gained a significant amount of fluid between dialysis sessions. If you feel uncomfortable during the procedure, ask your care team about minimizing side effects through measures such as adjusting the rate of your hemodialysis, your medication or your hemodialysis fluids.
- Supervision.Como sua pressão arterial e frequência cardíaca podem flutuar à medida que o excesso de líquido é removido de seu corpo, sua pressão arterial e frequência cardíaca serão verificadas várias vezes durante cada tratamento.
- Refinement.When hemodialysis is complete, the needles are removed from the access site and a pressure bandage is applied to the site to prevent bleeding. Your weight can be re-registered. Then you can continue with your normal activities until the next session.
If you have had sudden (acute) kidney injury, you may only need hemodialysis for a short time until your kidneys heal. If you had reduced kidney function prior to sudden kidney injury, your chances of fully recovering and becoming independent of hemodialysis again are slim.
While in-center hemodialysis three times a week is more common, some research suggests that home dialysis is linked to:
- Better quality of life
- greater well-being
- Reduced symptoms and less cramps, headaches and nausea.
- Better sleep patterns and energy level.
Your hemodialysis treatment team monitors your treatment to ensure that you are receiving the right amount of hemodialysis to remove enough waste from your blood. Your weight and blood pressure are closely monitored before, during and after treatment. About once a month you will receive these tests:
- Blood tests to measure your urea reduction rate (URR) and total urea clearance (Kt/V) to see how well your hemodialysis is removing waste from your body
- Assessment of blood chemistry and evaluation of blood count.
- Measurements of blood flow through your access site during hemodialysis
Your care team may adjust the intensity and frequency of your hemodialysis based, in part, on your test results.
Between hemodialysis treatments, you can help get the best possible results from your hemodialysis by:
- Eat the right foods.Eating right can improve your hemodialysis results and your overall health. During hemodialysis, you will need to carefully monitor your fluid, protein, sodium, potassium and phosphorus intake. A registered dietitian can help you develop an individualized eating plan based on your weight, personal preferences, remaining kidney function, and other medical conditions such as diabetes or high blood pressure.
- Take your medications as prescribed.Carefully follow the instructions of your healthcare team.
- Let your team help you by discussing your concerns.Your healthcare team can provide you with options and help you deal with any concerns.
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