Hemodialysis: Understanding dialysis

Doing the Job

The process in dialysis is to clean the blood of waste products, restore the proper balance of electrolytes and remove extra fluid.  

Blood passes through a filter called a dialyzer which is part of the hemodialysis machine. For most patients, the treatment takes 4 hours, three times a week. 

In-visit Treatments

Patients have their dialysis in the hospital as an out-patient and monitored by nephrologists, nurses and other key staff members.

Dietitians are also a key component for dialysis patients to ensure they are eating dialysis-friendly foods. In addition, to the unit Pharmacist will monitor medications and side effects that may occur with dialysis.

How a hemodialysis machine

works for you!

1.   Access Site

Two tubes are connect to your hemodialysis  access port.  Blood flows from your body into the machine through one of the tubes. 

2.  Dirty Blood

If additional medications are required during dialysis it will be added as part of your treatment.

3.  Pressure Pump

A pressure monitor and pump work together in keeping the flow at the correct rate.

4.  Dialysate Enters

Your blood enters the dialyzer which acts as an artificial kidney where the blood is filtered.

That part of a mixture that passes through a dialyzing membrane; the material that does not pass through is referred to as the retentate.

5.  Dialyzer

Dialysate solution enters  the dialyzer and it draws the waste out of your blood.

7.  Air Trap Check

Your blood goes through another pressure monitor and an air trap to ensure it is safe to go back into your body.

6.  Used Dialysate Discarded

Used dialysate solution is pumped out of the machine and discarded.

8.  Blood Returned

Your cleaned blood returns to your body through the second tube, attached to your access site.  

Vascular Access for Hemodialysis

Arteriosclerosis (AV) Fistula

An arteriosclerosis (AV) fistula is a surgical connection between a vein and an artery created by a vascular specialist.

An AV fistula is normally inserted in the arm, and if necessary, it can be placed into the leg.

Forearm and hand showing vein and artery connected by stitches. Arrow shows blood flow going from artery to vein.

Arteriosclerosis (AV) fistula

Venous Catheter

A venous catheter is a tube inserted into a vein in the neck, chest, or leg near the groin, usually only for short-term hemodialysis.

The tube splits in two after the tube exits the body. The two tubes have caps designed to connect to the line that carries blood to the dialyzer and the line that carries blood from the dialyzer back to the patient.

Venous catheter

Arteriovenous (AV) Graft

Arteriovenous (AV) graft Is created through a surgical procedure in which the surgeon connects an artery to a vein using a small tube.

Arteriovenous (AV) Graft

Arteriovenous (AV) graft

The two sides of Hemodialysis


  • Relieves symptoms of uremia
  • Requires at least three treatments a week, for approximately four hours
  • Vascular access for hemodialysis

Keep in Mind

No matter the choice in your dialysis treatment, it is paramount that you keep the communications open with your medical support team. It is natural to feel overwhelmed and scared. 

Though it is easy for one to say, however, if you can stay calm, stay positive and keep the channels open in expressing your feelings and concerns, you will feel a whole lot better and have better treatment outcomes.


  • Permanent access point
  • You will have to take medications
  • You will need to learn new food choices
  • You will need to prevent the catheter from getting wet - no swimming or full body showering
  • You must plan your week around your hemodialysis schedule (although with home hemodialysis, you can plan your treatment schedule around your week)
  • You may need to travel some distance to the hemodialysis unit.
  • Some people do not have suitable blood vessels for establishing an access site.

Taking additional care of your access

Do not allow anyone to take a blood pressure reading on the same arm with the access.

While sleeping avoid placing pressure on the arm where the access is located.

Avoid placing pressure on the arm when you are lifting heavy items.

Do not allow any blood to be drawn from the arm.

Do not wear tight clothing around the access site or on the arm.

Do not use creams or lotions over the access site

2 Common Fruits That Can Have Deadly Consequences

Star Fruit


Research has shown that starfruit contains a nerve toxin that can cause confusion, agitation, and in some cases death.  Starfruit also known as Caramobla can be life threatening for those on dialysis.



If you do eat grapefruit or drink grapefruit juice, check with your doctor to make sure it is not harming you.  Grapefruit and grapefruit juice, can interact with many medications.

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