Renal dialysis Flashcards
What is renal dialysis?
Process by which the solute composition of a solution “A” is altered by exposing it
to a second solution “B” through a semi permeable membrane.
Think osmosis - A solute dissolved in a solution will travel from an area of high concentration to an area of low concentration via a semi permeable membrane. So, if the concentration of e.g. salt (sodium) in the
patient is high and the concentration of the second fluid is low in sodium, the sodium will travel across
the membrane and can be excreted providing we can bring these two fluids close enough together.
What are the two types of dialysis?
Haemodialysis
Peritoneal dialysis
What are the requirements for haemodialysis and peritoneal dialysis?
The requirements are the same for both:
1)Semi permeable membrane.
2)Anticoagulation.
3)knowing how much solute and fluid to remove.
How is haemodialysis done?
An arteriovenous (AV) fistula is interred into the patient, usually in the forearm. This provides permanent access points.
Using one fistula access point blood is
transferred, at a low flow rate, from
the body to the machine. Heparin is
then added to the blood to prevent
clotting, and the blood is passed into
the dialyser where the waste products
and toxins are removed. The cleaned
blood is then returned to the body via
the second fistula access point.
How is peritoneal dialysis done?
Peritoneal dialysis takes advantage of the
peritoneal membrane surrounding the
intestine being a natural semi-permeable membrane.
Dialysis fluid is introduced to
the abdominal cavity, where waste products transfer through the peritoneal
membrane into the fluid, thus doing the
work normally done by the kidneys.
On draining the abdomen, the waste is
removed.
What is AV fistula bleeding and how can it be stopped in both minor and major incidents?
Bleeding of the AV fistula.
Minor- careful direct pressure over the site and elevate. Assess for infections, swelling ect.
Major- direct pressure over the site and elevate limb. Use a lid of a plastic bottle to create direct pressure over AVF site. Indirect pressure above and below the fistula site.
What is a common problem of peritoneal dialysis?
Almost half of all PD patients will experience an EXIT SITE INFECTION within one year. Patients are made aware of all the warning signs and often self present to clinic.
Also PERITONITIS.
