What are the various forms of treatment available for a patient with
end-stage kidney failure?
There are 3 methods of renal replacement therapy available: Hemodialysis using the artificial kidney, Peritoneal Dialysis by
introducing a special solution into the abdomen, and Renal Transplant
from a cadaver or a living related donor.
What is dialysis?
Dialysis is a process which separates solutes dissolved through in water
a semipermeable membrane.
What happens in hemodialysis?
In hemodialysis the patient's blood is let out of his body where it is
treated with anticoagulant ( heparin ) to prevent it from clotting and
passed over a semipermeable membrane in the dialyzer ( artificial
kidney ) through which exchange of solutes ( dialysis ) takes place.
The blood returning to the patient after passing through the dialyzer
( artificial kidney ) is almost devoid of toxic substances.
What is vascular access and how is it made possible?
In order to get the patient's blood to flow out and pass through the
artificial kidney machine for cleansing, a vascular access is necessary.
Put simply, the access is a point for entry into the bloodstream so that
the patient can be connected to the machine.
The most common form of vascular access is the arterio-venous (AV)
fistula. The other types of access are the AV shunt and the subclavian
catheter. The AV fistula takes a few weeks to mature while the AV
shunt and the subclavian catheter can be used immediately.
What are the equipment required for hemodialysis?
The patient requires a hemodialysis machine with a built-in system
to monitor the various sets of pumps, the dialyzer or artificial kidney,
lines for letting out and returning blood to the patient, dialysate or
dialysis solution, water treatment unit ( deioniser or reverse osmosis )
and vascular access for the patient ( usually an AV fistula ).
When should a patient be considered for dialysis?
A patient should be considered for dialysis or transplant as soon as it
is clear that he or she has chronic renal failure, usually with a serum creatinine level of about 7 to 8 mg. The doctor would usually suggest an
operation for an AV fistula at this stage.
Dialysis is started when the serum creatinine level is about 12 to 15
mg though occasionally it is started earlier when the patient has
symptoms of renal failure.
How are patients selected for hemodialysis?
Acceptance policies in different countries vary considerably. Some
countries accept any patient wishing treatment while many others select
patients using age, medical, economic and other factors as the criteria
because of financial constraints.
What is home dialysis?
This is the best option for the patient on dialysis. The patient can dialyse himself after office hours at his own convenience with the aid of
his spouse or partner. Employers are happier and such patients are
more productive, compared to those dependent on the centre or self-
dependency dialysis. In Singapore, home dialysis is actually private
dialysis unlike the government-supported self-dependency dialysis. The
set up for home dialysis includes a dialysis machine and a water
treatment unit ( reverse osmosis or deioniser ). Together they cost about
$15,000 to $20,000 with a recurrent monthly expenditure of about $800
for disposables like dialysers, dialysate and blood-lines. It is obvious
that not many can afford to dialyse at home.
What is the effect of hemodialysis on the patient?
Initially, most patients will experience some after-effects with life on hemodialysis. Some may feel unwell at the end of each dialysis, feeling a
bit washed out. During dialysis they may have cramps, vomiting or
hypotension. These effects are caused by the changes occurring in the composition of the body fluids. However most patients get over these
effects after a few weeks. The majority of patients will have the feeling
that they have been given new lives as they no longer suffer from
symptoms of end-stage renal failure, such as nausea, vomiting,
shortness of breath, giddiness and tiredness. Even food tastes better
and everything in their body seems to work well again.