Hemodialysis

What is Hemodialysis?

This is a form of kidney replacement therapy that uses a filter to remove toxins and excess fluid from the patient’s blood.

When is Hemodialysis done?

This is done when the degree of kidney failure is severe enough that the patient’s overall health and well-being is affected.  Dialysis is used as a replacement of kidney function in either Acute Kidney Failure or Chronic Kidney Disease.  It does not help with the recovery of kidney function.

In the case of AKI, dialysis may be required temporarily until the kidney function improves.  In cases of advanced CKD, dialysis is often required life-long or until a kidney transplant is done.

How Hemodiaysis is done

1. Creation of vascular access: can be via a dialysis catheter, arteriovenous fistula (AVF), or a arteriovenous graft (AVG)
2. Removal of blood from the patient via the arterial line
3. Blood pumped through a dialysis filter. The following processes occur through the filter:
   • Toxin removal
   • Certain substances replaced (ex. Bicarbonate)
   • Fluid removal
4. Return of this cleaned blood to the patient via the venous line

Complications of Hemodialysis

Complications of hemodialysis include those associated with vascular access (discussed in section on vascular access) and with the procedure of dialysis itself.

During and after dialysis, blood pressure changes can result in various symptoms:

• Leg cramps – usually with a drop in blood pressure
• Lightheadedness – usually due to fluid removal and lower blood pressure
• Abdominal discomfort, nausea/vomiting
• Fatigue

Rarely, patients may have seizures or may experience arrythmias of the heart.  Some patients may experience reactions to the dialyzer. 

Most complications can managed by adjusting the dialysis parameters, with use of certain medications or stopping the session.