Hemodialysis

Dialysis is a method of treatment of terminal renal failure. When the kidneys are no longer working effectively, waste products (toxins) and fluid builds up in the body. Dialysis takes over the functions of the kidneys are failing and removes waste products and fluid.

Dialysis is usually required when the lost 90 percent or more of kidney function. This behavior usually occurs several months or years after the diagnosis of chronic kidney disease. At the beginning of kidney disease used other types of therapies that help maintain kidney function and delay the need for renal replacement therapy.

What type DIALYSIS BEST? - When dialysis becomes necessary, the patient (with the doctors) examine the pros and cons of the two types of dialysis:

Hemodialysis (in the center or at home)
Peritoneal Dialysis
The choice between hemodialysis and hemodialysis peritonumske influenced by many factors such as availability, convenience, underlying medical problems, the situation in the home and age. This decision is best made after discussion with your doctor about the risks and benefits of both types of dialysis.

When you start dialysis - Together with the doctor, the patient decides on the time of starting dialysis, according to the kidney failure. The decision affect renal function (as measured by blood tests and urine tests), overall health, nutritional status, symptoms, quality of life, personal preferences and other factors. Doctors recommend that dialysis begin much before the kidney disease has progressed so much that can be life-threatening complications.

Many patients have to start dialysis when renal function is 8 to 12 percent of normal, even though it varies from patient to patient.

In some situations, dialysis must immediately begin. If the blood tests suggest that this is a very poor kidney function or non-existent, or if there are symptoms such as confusion or bleeding associated with kidney disease, the application of dialysis should be started immediately.

Preparation for hemodialysis - Preparation for hemodialysis should be made at least a few months before it becomes necessary. In particular, the procedures needed "vascular access" (described below) for a few weeks or months before treatment.

Vascular access - Vascular access to collect blood from the bodies of patients, its treatment in the dialysis machine and back into the body of the patient. There are three main types of vascular access: primary AV fistula, synthetic AV grafts and central venous catheter. Other names for access to the fistula or shunt.

The approach needs to be made before the start of dialysis because of the time needed for its "maturity". Consultation on Access to begin even earlier, because he has to avoid injury to the vessels that will be used for it. Intravenous infusion or frequent blood sampling from the arm that will be used to create vascular access can damage veins, which subsequently makes it impossible to use those for vascular access. Access is usually on the right hand that is not dominant; lefthanded people will have access to the left hand.

After the formation of vascular access is very important to monitor it and take care of him.

Primary AV fistula - Primary AV fistula is the most common type of vascular access. Requires a surgical procedure that makes a direct connection between arteries and veins. This is often done on the forearm, but it can on the upper arm. Sometimes, the veins that normally would not be useful for creating AV fistulas may be moved so that it is accessible and this can often be performed on the upper arm.

Regardless of the position or the way in which it is made, access under the skin. During dialysis, the approach introduces two pins. Through a needle of blood out of the body, passes through the dialysis machine and back into the body through another needle.

Primary AV fistulae usually makes two to four months before they will be used for dialysis. During this time, the wound will heal and access will be fully developed and "mature."

Synthetic graft - Sometimes the veins in the hand of the patient are not suitable for the creation of the fistula. In this case, the surgeon can use a flexible rubber tube in order to make a path between arteries and veins. This is called a synthetic graft. Graft under the skin and is used in the same way as the fistula.

Graft heals faster than fistulas can often be used for two weeks after installation. However, complications such as narrowing of the blood vessels and infection occur more frequently than in the case of graft AV fistula.

Central venous catheter - Central venous catheter using a thin flexible tube that is inserted into a large vein (usually a door). Recommended if dialysis must immediately begin, and the patient does not have a functioning AV fistula or graft. This type of approach is usually used only temporarily. In some cases, however, there may be problems with the maintenance of AV fistula or graft, and central venous catheter permanent access.

Catheters have the highest risk of infection and the worst position in comparison with other approaches; should be used only if the primary fistula or synthetic graft can not be sustained.

Changes in diet - Some patients, especially those made in the dialysis center, it will have to make changes in your diet before and during treatment. These changes are provided to prevent overloading and liquids to enter a balanced amount of protein, calories, vitamins and minerals.

Can you recommend a diet low in sodium, potassium and phosphorus, and fluids (drinks and food) may be limited. A dietitian can help patients when choosing foods that are compatible with dialysis treatment.

LOCATION hemodialysis treatment - hemodialysis can be performed at home or in the center.

Home treatment - treatment for pets is essential that the patient and members of his / her family educated and constant support physicians experienced in the treatment of patients on home hemodialysis. This usually means nephrologist (kidney specialist) and too specialized nurse.

Patients treated with hemodialysis at home usually can lead an independent life and often have longer survival compared to patients treated in a dialysis center. This is partly due to the fact that patients on home hemodialysis have more frequent and longer dialysis treatments of patients at the center.

Home hemodialysis is generally performed three to seven times a week and lasts between three and ten hours after treatment. Hemodialysis, which is done during the day usually takes three to four hours a day, four to seven times a week. Hemodialysis, which is done at night (nocturnal hemodialysis takzvana) is usually performed three to seven times a week while the patient sleeps. Preparation and cleaning needed more time.

Home dialysis can be done at a time that suits the patient. Usually require the participation of another person (family member, friend or technician) who helps the patient before, during and after dialysis.The doctor has to be a phone available in case of problems or issues; daily (or nightly) dialysis schedule provides additional benefit compared to treatment at the center, which is done three times a week. More frequent dialysis results in a significant increase in health, reduce symptoms during and between dialysis and improves the quality of žifvota. Home dialysis can improve quality of life as to download more responsibilities related to care of themselves and to staying in the comfort of the apartment during the treatment. In addition, patients who use home hemodialysis can usually keep their job.

Equipment - For home dialysis is necessary that the patient has a dialysis machine at home. In addition, the system is required for the preparation of water for hemodialysis (reverse osmosis), dialyzers, dialysis solutions, disinfectants, syringes, needles, drugs, blood lines and sets to test the waters. Some devices need electrical and plumbing modifications of the house in which dialysis is performed. Currently available equipment for the size of night-table.

Treatment center for dialysis - Dialysis can be performed in a hospital, clinic associated with a hospital or an independent clinic. The centers employ doctors, nurses and carers and all involved in the care.Generally, the dialysis center takes between three and five hours (an average of three and a half to four hours) and is performed three times a week. During treatment the patient can sleep or read and usually has access to a television. The HD unit consumption of food and beverages, as well as visits are usually limited.

Travel Tools - Dialysis centers are located all over the world. Patients who need dialysis, but who want to travel scheduling consultations in the center of the village in which they want to travel (temporary center). Many dialysis centers have an employee, nurse or social worker, to help in organizing the visit; planning should be done six to eight weeks prior to travel to ensure a place.

Dialysis center where the patient has regular treatments temporary center must provide the patient's medical history, including the results of recent tests and information about treatment, list of medications, insurance information, and any other necessary information.

Patients with chronic medical problems, including those requiring dialysis, the trip must be carefully planned.

Monitoring the quality HEMODIALYSIS

In patients treated with hemodialysis are regularly doing lab tests to check the quality or adequacy of hemodialysis. Modern dialysis machines have all the modules during dialysis showed the same quality.Based on the results of these tests are set conditions hemodialysis (blood flow velocity, length of dialysis, type of dialysis filter, etc.).. Numerous clinical studies have shown that the efficiency and adequacy of hemodialysis affect survival of patients as well as in the quality of life. Assessing the adequacy of dialysis should be done at least once a month.

Monitoring body weight - After failing kidneys that can not remove the required amount of fluid from the body, the task must be performed dialysis. Accumulation of fluid between two hemodialysis treatments can lead to complications. Most patients measure the weight before and after dialysis and are looking for an everyday weight control at home. If the patient's weight between the two treatments increased more than normal, he must contact his or her doctor.

Care Access - It is very important to take care of vascular access in order to prevent complications.Complications can occur even when the patient is alert, but less if you take certain precautions:

Access daily washing with soap and water, and always before starting. The patient should not be slate or removes scabs.
Every day check whether there are symptoms of infection such as redness or to the temperature.
Daily check to see if there is access to the blood flow. You need to feel the vibrations through access.Tell your doctor if there is none, or change. Blood flow is sometimes controlled by ultrasound (Doppler). Monitoring the flow and velocity of blood flow through the access during treatment.
Hand with approach must not be violated; patient should not wear tight clothes, jewelry, or heavy things to sleep on that arm. You should not allow blood tests or blood pressure in the arm.

Unwanted effects on hemodialysis - Most patients well tolerated hemodialysis. However, I can report adverse events. Low blood pressure is the most common complication and may be accompanied by dizziness, shortness of breath, abdominal cramps and muscle pain, nausea and vomiting.

For any inconvenience that may occur during hemodialysis, treatments and preventive measures.Many side effects are associated with excess salt and fluid accumulation between treatments, which is minimized by carefully monitoring the amount of salt and fluid enters the patient between two dialysis.

Hemodialysis-patient information

As patients, their families and carers need to know?

Hemodialysis (HD) is the most common form of treatment of patients with terminal renal failure. If you start treatment with hemodialysis, it means that you there is still only 10-15% of normal kidney function. It is not enough to cleanse the body of toxins and keep healthy. At that time you have symptoms such as anemia, nausea, vomiting, fatigue and sweating (especially the palms, feet and ankles).

It is important to know that hemodialysis is not a cure for your sick kidneys. By the time you be healthy transplanted kidney, you will need to be treated with some form of dialysis, sometimes for life.Some patients have lived 35 more years on hemodialysis. They can tell you how important it is to stick to strict schedules of dialysis, medications are prescribed and the child to have a long and productive life as a terminal kidney patient.

How is hemodialysis?

Nearly 90% of patients in terminal renal dialysis centers in 3-5 hours of dialysis three times a week. In most centers this is done on schedule Monday-Wednesday-Friday or Tuesday-Thursday-Saturday, and the time is morning, afternoon or evening. During hemodialysis using a special machine and the filter used for blood purification of patients. This is done by surgically constructed to access the bloodstream, usually on hand, as described earlier.

Dialysis membrane filter is divided into two parts. The first is the blood of patients that leads from the body and cleanses the toxins, and then back into the body. The second is called the dialysate fluids used for Ťispiranjeť. Sewage purposes of substances from the blood such as urea, potassium, creatinine and excess fluid pass through the dialysis membrane and is removed by the dialysate.

The adequacy of hemodialysis

In the initial implementation of chronic hemodialysis (60's and early 70-ies of the 20th century), nephrologists did not know how dialysis takes to keep patients healthy. Once you have learned how to maintain blood values ​​essential substances, eg. potassium, optimal, put the problem in order to maintain long-term patients and healthy living. Patients suffering from complications such as infection and inflammation.

It was found that many of these complications can be reduced or even removed a longer time interval of the dialysis (8-12 hours), and patients to accept in the hope that makes them relatively healthier. Nephrologists have noticed that their patients will not accept a longer time interval of dialysis and began to explore the value or Ťmarkereť that will help them to more accurately determine the amount received adequate dialysis therapy.

"Markers" adequacy of dialysis

Following some of the "markers", doctors have found a more precise way odeđivanja adequacy of dialysis therapy.

- Urea or blood urea nitrogen levels in the blood: Urea is a waste product of protein that we take food to digest and break down and which are normally excreted in urine. Nephrologists found that patients in worse condition that it is the level of urea in the blood higher. Urea is a small molecule that is removed through the dialysis membrane. In dialysis scheme Monday-Wednesday-Friday, the level of urea in the blood is highest on Monday before dialysis, and the lowest on Friday after the last weekly dialysis.

- Kt / V: Two well-known nephrologists have discovered a simple formula for the measurement of dialysis therapy. "K" is the "clearance" of urea in milliliters per minute. TTT has Ťvrijemeť in minutes, a "V" the volume of body water in liters. Since the formula used by the individual volume of each patient's body fluids, resorted to the "standardization", because patients who are equally heavy volume can have different body fluids. Experts have recommended the value of Kt / V of 1.2 or more as optimal for adequate diajlize.

- Urea kinetic model: using the value of Kt / V for the definition and measurement of dialysis therapy.This "marker" is used the level of urea in the blood before and after dialysis, analyzes of protein metabolism and protein shows that the patient currently has in their diet. At first the doctors thought it was better if the patient takes less protein in their diet. Further experiments showed that it is better that the patient consume more, not less protein. Anyway, today is the attitude of medicine such that the part of patients with residual renal function advises restricted protein intake to maintain the healthy function. It is very important that you consult with your nephrologist about the amount of protein in the diet that is most appropriate for you.

- The ratio of urea elimination: elimination of urea, the end result of dialysis, is a measure used to determine the efficiency of elimination Waste products of metabolism from the body. This "marker" is expressed as a percentage. Significant world health authorities recommend 65% or more and is usually measured once a month. The ratio of urea elimination of 65% is equivalent to the value of Kt / V of 1.2.The ratio of urea elimination of 65% and the value of Kt / V of 1.2 as the optimum value of dialysis adequacy. Numerous studies have shown that patients with a permanently lower Kt / V or lower ratio of urea elimination have more health problems and increased risk of death.

Home hemodialysis

Several years ago, more and more patients and nephrologists has documented the benefits of implementation of dialysis at home, because if there are opportunities. Several hundred scientific papers published on the subject in the last three decades. Patients can learn to perform hemodialysis three times a week at your own home. Some patients practice daily or nocturnal hemodialysis (6-7 times per week). The data suggest that patients who are dialysis longer time interval several times a week at home, live longer than those who do it three times a week at dialysis centers.

Hemodialysis - dialyzer

Hemodialysis is done so that blood flows out of a special tube and purified, and then distilled back into the body of another tube.

In the process of dialysis are important parts:

dialyzer

device for hemodialysis

Solution for hemodialysis

equipment (needles, tubes)

The most important part of the dialyzer or artificial kidney, which contains a semi-permeable membrane to form capillaries. Through this membrane pass only molecules of certain sizes and water.

Dialyzer is attached to a dialysis machine and changing with each dialysis.

The dialysis solution or dialysate is an electrolyte solution similar to plasma without proteins. The solution maintains the electrolyte balance and participates in the process of purifying the blood.

The device is a dialysis machine that contains the prepared dialysate pump, and pump blood and to maintain a constant temperature of blood and dialysate to their steady flow.

Most patients have dialyis to 3 times a week and the process takes approximately 4 hours.

Vascular access

Patients undergoing hemodialysis should have access to the path of blood in the form of hemodialysis arteriovenous fistula, graft or catheter. When creating a small fistula surgeon procedure under the skin, usually on the wrist connects the artery and vein. If blood vessels are too weak to make a fistula is formed graft (graft blood vessels), and catheters are typically used temporarily, but may be permanent.

When you establish an adequate approach to the patient with two outputs are connected to the device for hemodialysis. Questions are two pins, soft tubes connected part that comes from the arteries leading into the camera, and the part that comes out of the device leads to a vein.

HISTORY OF DIALYSIS

First century. pr. BC: In China records first mentioned organ transplantation under general anesthesia.

13th st: Giugliermo Saliceto in Durities in Renibus: "The pressure in the kidneys ... or can not be treated successfully, or can not be cured."

17th century. William Shakespeare: Henry IV.

Falstaff: "What does the doctor about my water?"

Page: "He says, sir, that water is in itself a good, healthy water, but its owner would have to have a disease which is not conscious."

1861st Thomas Graham introduced the concept of the physical chemistry of making use of selectively permeable dialysis membrane to separate big molecular substances and low molecular substances from solution.

1922nd It was discovered in heparin, but it began as a systemic anticoagulant prescribed only twenty years later. Until then prescribed hirudin, an anticoagulant, which is very uncertain is received from the heads of leeches.

HEMODIALYSIS

1924th Haas George spent the first successful hemodialysis in patients with end-stage renal failure.Dialysis lasted 15 minutes and went without complications.

1944th Willem Kolff in the Netherlands, then under Nazi occupation, constructed the first device for hemodialysis. As a dialysis membrane was used cellophane. Kolff was after the war emigrated to the United States has developed several other hemodialysis machines that were used in the Korean War.

1946th Nils Alwall produced the first hemodialysis machine with controlled ultrafiltration.

1960th Belding Scribner made the first permanent vascular access, thus creating the foundation for the development of chronic hemodialysis. Fistula is composed of two tubes embedded in the blood vessels, which were then merged together with a piece of Teflon placed on a steel plate. A few years later created a simpler version of such a vascular access, so called. "Shunt poor." It consisted of two tubes embedded in the artery and vein and connected teflon loop.

1962nd In Seattle, he began to work the first center for chronic hemodialysis. The first patients were Clyde Shields (died in 1971. In) and Harvey Gentry (died in 1987. In).

1966th Cimino and Brescia were first described subcutaneous arterio-venous fistula, obtained by connecting the radial artery and vein. Such a form of cardiovascular approach used today in patients on chronic hemodialysis.

R. The Hickman and B. H Scribner become effective hemodialysis in children.

Haemofiltration

1966th In the U.S. and Germany conducted the first tests of new membranes for dialysis, propusnijih for midsize molecules.

1977th Kramer is, when setting up a system for haemofiltration, mistakenly punktirao femoral artery instead of vein. Artery blood pressure was sufficient to maintain the extracorporeal blood flow. In this way the first time carried out continuous arterio-venous hemofiltration (CAVH).

1982nd Bischoff puncturing the femoral vein and the addition of blood pumps in vitro bloodstream achieve greater and greater blood flow ultrafiltration. This resulted in continuous veno-venous hemofiltration (CVVH).