http://nephron.com/fkg.html
by Stephen Z. Fadem, MD
FACP
Medical Director, Houston Kidney Center
Integrated Service Network
Dialysis is a therapy which eliminates the toxic wastes from the body
when the kidney fails, and cannot do its job of eliminating these toxic wastes.
There are two types, hemodialysis
and
peritoneal dialysis.
In hemodialysis blood is pumped from the body to a filter made of tiny
plastic capillaries. The blood is purified when the waste products diffuse from
the blood across the membrane of these tiny capillaries. Purified blood is then
returned to the arm.
- Hemodialysis is performed in
a dialysis center for 4 hours three times a week.
- Dialysis is performed through
an arteriovenous access (a
v access)
- Advantages: No patient
training is required.
- Disadvantages: Dialysis graft
failure, lack of freedom
In peritoneal dialysis the bodies own membrane is used as a filter, and the
fluid drained in and out of the abdomen replaces the kidneys in getting rid of
the body poisons.
- It can be done at home, but
requires careful technique.
- Its advantage is more freedom
and less needle sticks.
- The disadvantages are
peritonitis and membrane failure.
Example of fluid draining in
Example of fluid draining out
- Creatinine clearance less
than 10 cc per minute in non diabetics who have adequate nutrition - make
sure access is functioning by then, and can be started as an outpatient is
the absence of severe anemia, acidosis, high potassium or uremic symptoms.
- Creatinine clearance less
than 15 cc per minute in diabetic patients, depending upon nutrition status
(Justified at even higher clearances if malnourished or in heart failure).
- Elderly and debilitated
patients may have low creatinines due to decreased muscle mass - GFR equates
to average of urea clearance and creatinine clearance.
- H2 blockers such as
cimedidine (Tagamet) impair the secretion of creatinine and give us a more
accurate reflection of clearance. Use with a six hour collection
- Erythropoietin - Control of
anemia is very important to protect the heart, and to maximize energy.
- Dialysis Adequacy - The
better the quality of your dialysis, the more waste products are removed,
and the better you feel. Dialysis adequacy is measurable. Know your number.
- Albumin - This is a marker of
nutrition, but if low can also signified that you are not adequately
dialyzed.
- Blood pressure control -
Start early to control your blood pressure. High blood pressure damages your
heart.
- Exercise - It is important
for dialysis patients to exercise as much as possible.
- Acidosis - This mineral may
build up in your blood, and can be controlled with medication.
- Access Pressures - A high
pressure in your graft arm may mean that the vessel leading from your graft
is narrowed, and that repair is needed to help protect your graft.
- Biocompatibility - Some
filters are more compatible than others. Check with your health provider.
- Peritoneal Dialysis Adequacy
- like in hemodialysis, you need sufficient amounts of peritoneal dialysis
in order to feel well.
- Cardiovascular abnormalities
- Heart attacks are common in kidney patients. Keep your cholesterol under
control.
- Infection - This is common in
dialysis patients. Keep your graft site clean, and note any sign of fever,
chills, sweats or weakness.