Urologic Diseases

Hemodialysis

​Introduction:

Hemodialysis is a medical procedure that purifies the blood from wastes, when the two kidneys no longer function properly. Hemodialysis is a treatment for severe (or end-stage) renal failure, so that the patient can perform the daily activities. In hemodialysis, a dialysis machine and a special filter called an artificial kidney, or a dialyzer, are used to clean (or filter) the patient's blood. To get the blood into the dialyzer, the doctor needs to make an access, or entrance, into the patient's blood vessels. This is done with minor surgery. The blood flows out of the body, passes through the dialyzer, before it is returned to the body, clean.

Other names:
Hemodialysis, blood dialysis, blood purification through an artificial kidney, dialyzing

Hemodialysis duration:
The patient with renal failure usually undergoes hemodialysis three times per week, four hours each. They may be increased or decreased according to the doctor's instructions. 

Advantages of hemodialysis:
  • Conducted in a dialysis center by experienced healthcare professionals, under medical supervision; 
  • Conducted for only some days per week, allowing the patient some freedom, to perform his daily activities normally during the other days;
  • Less susceptible to infection than peritoneal dialysis.

Disadvantages of hemodialysis:
  • The patient has to head to the hemodialysis center several times every week;
  • The patient should follow a specific diet, and limit the intake of fluids;
  • The patient is pricked more often;
  • Hemodialysis affects the shape of the arm in which the arteriovenous (AV) fistula is connected;
  • Travel is more complex, requiring advance planning and arrangements, as well as searching for hemodialysis centers.

How does hemodialysis work?
The blood flows out of the body, and then is returned to it, through two tubes connected to needles: one takes the blood out of the body, and the other returns it to the body, after purification by the dialyzer.

Preparing for hemodialysis: 
Preparation for hemodialysis starts several weeks to months before your first procedure. To allow for easy access to your bloodstream, a surgeon will create a vascular access. The access provides a mechanism accessing the needle through which the blood flows during a dialysis procedure. There are three types of accesses:
  • Arteriovenous (AV) fistula: A connection between an artery and a vein, usually in the arm. This type of access is more common, because of effectiveness and safety.
  • AV graft: If your blood vessels are too small to form an AV fistula, the surgeon may instead 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 tube (catheter) may be inserted into a large vein in your neck or near your groin. The catheter is temporary, and is more susceptible to infection and forming clots. 

Side effects:
  • Infection: Bacterial infection may occur in the access.
  • Complications potentially occurring during a hemodialysis procedure, including: low or high blood pressure, vomiting, cramps (especially of the abdomen and leg muscles), itching, etc. These complications are temporary, and easy to treat.

When to see a doctor?
  • Access bleeding;
  • Shortness of breath;
  • Chest pain;
  • Fever (body temperature is 38°C or higher);
  • Bloody urine or stool; 
  • Severe headache, or cramps;
  • Signs of infection on the catheter, including: 
o Discharge (oozing) from the catheter;
o Redness of the surrounding area;
o Fever;
o General weakness.

Caring for AV fistula or AV graft:
It is extremely important to take care of your access site to reduce the possibility of infection, and to preserve it for as long as possible. In addition to the instructions provided the healthcare provider, the following tips should be followed:
  • Avoid measuring blood pressure on the arm to which an AV graft or fistula is connected, or withdraw blood from it (for blood tests).
  • Avoid clothes with tight sleeves, or watches, and be careful when dressing and undressing.
  • Don’t sleep on the access area. 
  • Be cautious when using objects.
  • Keep your arm clean.
  • Make sure the fistula is working.

Caring for the catheter during bathing:
  • Avoid swimming, or spillage of water on the catheter.
  • Cover the catheter before bathing.
  • Make sure it is not wet.
  • It can be cleaned by wiping it with water and soup.

General tips:
  • Follow the diet prescribed by the healthcare provider.
  • Take the medications as prescribed by the doctor.
  • Limit the intake of fluids to the level prescribed by the doctor.
  • Plan and arrange for traveling in advance, and make sure that hemodialysis centers are available.
  • Don’t leave the hemodialysis center until the procedure is complete.
  • Be committed to the hemodialysis schedule, and the procedure duration.
  • Keep the catheter clean, dry and covered.
FAQ 
During hemodialysis, is it required to add blood products?
No, blood products may only be added when the need arises, as prescribed by the doctor.
Can hemodialysis be conducted at home?
Yes, under medical supervision.
Can the hemodialysis patient travel?
Yes, in coordination with the hemodialysis center.
What do Kt/v and URR refer to? Should the patient be aware of them, and monitor them?
They are two indicators for measuring the dialysis efficiency. And yes, the patient should be familiar with them, as well as all the other performance indicators (by asking the doctor).

Myths & Realities:
Hemodialysis is ineffective.
Reality: Not true. Hemodialysis, on the contrary, is very effective.
Hemodialysis is painful.
Reality: It is not, but it may cause cramps, which are easy to treat.
Hemodialysis is a curing treatment for renal failure.
Reality: No, hemodialysis is a substitution therapy.​




Last Update : 21 September 2021 10:24 PM
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