The artificial kidney should try to
mimic normal renal function as
much as possible. The main function
of the kidneys is the even maintenance of
the internal milieu, homeostasis, not only
the removal of urea. We should strive to
maintain normal electrolyte and acid-base
balance and normal fluid volumes in the
body. This is achieved with long, daily,
smooth dialysis. The removal of urea is
one, and not the most important, of many
kidney functions, yet we dialyze as if the
only renal function was urea removal.
Chronic hemodialysis in the USA has
been a quantitative triumph and a qualitative
failure. From a handful of people being
dialyzed at the end of the 1960s, an enormous
organization has been built up that
accepts over 100,000 patients annually —
1 every 5 minutes — and cares for over a
quarter of a million people. It is an impressive
story, and one should be proud to
have participated in it.
The success of chronic hemodialysis
as measured in survival, morbidity, and
quality of life, is another, sadder story. Data
from the early European Dialysis
Transplant Association (EDTA) Registry
indicated that the 1-year crude mortality
rate fell from about 50% in the 1960s to
10% in the early 1970s. The US National
Dialysis Triangle Registry reported a cumulative
1-year mortality in 1970 of only 10%.
Since that time mortality almost tripled to
25% in 1990, and has since shown a modest
decline to about 23%. It is better to
develop cancer of the breast or prostate
than to need chronic dialysis in the USA in
the year 2000! The increasing death rate is
unprecedented. In all other diseases
employing high technology medicine, such
as coronary bypass, HIV, hypertension, and
diabetes, mortality rates have improved.
One explanation for the rising mortality in
the USA has been that older patients with
more comorbidity and worse diagnoses are
accepted. The same is true for Japan, second
to the USA in accepting patients for
dialysis, but their mortality rate, which
bottomed out at 9%, has only recently
risen to 10%. All other high technology
treatments are also accepting older and
sicker patients, such as those with dia-betes;
still, the results have improved.
Dialysis is unique in experiencing a wors-ening
mortality. I believe the major reason
for the miserable results of chronic dialysis
is that we dialyze in an increasingly unphysiologic
fashion.
If one considers the reasons for these
awful statistics in the USA, they can be
divided into patient problems that limit
survival and problems with the hemodialysis
procedure that should be improved.
Advanced age and many comorbid conditions
limit survival, but when the patient
comes for dialysis, we can do nothing
about these. With hemodialysis there are
four areas where improvement can be
achieved: higher small molecular removal
(higher Kt/V), more-physiologic dialysis,
better middle molecule removal, and better
biocompatibility. The best clinical studies
indicate that the last two are of lesser
importance, and that more-physiological
dialysis is the best way to improve mortality.
A higher Kt/V is the second most important
factor.
Dialysis has become increasingly
unphysiologic. The early hemodialyses
were long affairs, 8 –12 hours. In the USA,
because of commercial pressures, and in
other countries because of budget constraints,
dialysis was increasingly shortened
to the current 2 1/2 – 3 1/2 hours,
only one fourth as long. Because of the
preoccupation with dose (Kt/V), it was
erroneously assumed that as long as the
result of the numerator, K x t, was maintained,
all was well. This assumption is
wrong. A greater K cannot compensate a
short t. A long t is necessary for fluid and
sodium removal, and thus, blood-pressure
control. Short, ultrafast dialysis can never
maintain the homeostasis necessary for
extended survival and decreased morbidity.
In Japan, as in the USA, short dialysis is
dangerous. Overall, Japanese patients have
only one third the risk of dying in a given
time period compared to USA patients;
however, the Japanese patients who dialyze
as short and fast as USA patients, have the
same awful death rate as in the USA. In the
Tassin, France, clinic with the world’s best
survival, patients are still dialyzed 8 hours.
Practically none of the patients is on medications
for high blood pressure, compared
to some 70% of all USA hemodialysis
patients. Homeostasis cannot be maintained
with short, fast dialysis. Just as
speed on the road kills, so it does in
hemodialysis.
Short, fast dialysis also started a
vicious cycle. Short, fast dialysis leads to
more troubles than long, slow dialysis.
Patients experience cramps, nausea, vomiting,
headaches, and fatigue. Patients then
naturally demand shorter and shorter
dialysis so as not to have this misery prolonged.
It will be necessary to explain to
them that this short and fast dialysis is very
dangerous to their survival, and longer,
gentler dialysis will eliminate these symptoms.
Patients also benefit from higher Kt/V
dialysis than is now given. The Dialysis
Outcomes Quality Initiative (DOQI) guidelines
of a Kt/V of 1.2 – 1.3, three times per
week, is far from optimal. Data from Park
and Keshaviah and from the Japanese dialysis
registry show continued survival
improvement until a Kt/V of 1.6, and the
healthiest dialysis patients are those on
long nocturnal dialysis with weekly Kt/V of
up to 12! These patients need neither
blood pressure medications nor phosphate
binders, and no or much less erythropoietin.
Most of these expensive medications
with unpleasant side effects are required
due to infrequent and insufficient
hemodialysis. Most of the complicated
dialysis equipment with “sodium ramping
or profiling” and hematocrit monitoring to
avoid shock are necessary only because of
dangerous fast dialysis. This is absurd!
It was clear in the first 2 years of
chronic hemodialysis that increasing the
frequency of dialysis was very important.
Dialysis for vital indications and once or
twice weekly dialysis were quickly abandoned
for three-times weekly dialysis, but
the logical conclusion of daily hemodialysis
as the best dialysis was not drawn. The
logistical pressures of a great increase in
the number of patients, budgetary constraints,
and profit motives were the reasons
for this. However, since the early days
of chronic dialysis, there have always been
pioneers, trailblazers, and heroes of dialysis
who have not been satisfied with the
poor results of chronic hemodialysis as
generally practiced. Since that time, close
to 100 articles and abstracts dealing with
daily hemodialysis, from over 30 clinics
and including observations of over 250
patients, have uniformly showed improvement
in hematology, blood pressure,
nutrition, hormone levels, phosphate control,
problems during and between dialysis,
quality of life, hospitalizations, and
rehabilitation.
The world’s best long-term survivals
are those achieved in Tassin, France, with
very long, slow dialysis, and with an average
Kt/V of 1.79. A young patient in Tassin
has only one fourth the risk of dying during
the first 10 years of dialysis, compared
to a young dialysis patient in the USA. The
result for older dialysis patients, particularly
vulnerable to the many side effects of
short, hypereffective dialysis is even more
astounding. A 65-year-old dialysis patient
in the USA has a mortality risk 12 times
greater than a 65-year-old patient in
Tassin. The preliminary data from long,
nightly dialysis, the most effective and
physiological dialysis, show even better
survival. The very preliminary survival
results of shorter, daily hemodialysis
appear to be equal to those in Tassin.
Considering the aggregate of all these
data, it is clear that we are not giving our
patients the best dialysis. Why should we
be satisfied with three dialyses per week
when each added dialysis leads to
improvement? We do not treat hypertension
every other day. We do not stop
insulin on diabetic patients on the weekends;
yet we dialyze, and therefore, treat
the hypertension of dialysis patients only
every other day, and we let patients go
without dialysis for 3 days over the
weekend, when many develop life threatening
fluid overload and hyperkalemia.
Dr. Teschan pointed out in the 1950s that
one should treat these conditions in
patients with acute renal failure before
they became life threatening. The result of
low efficiency CAPD, the most physiologic
dialysis form, teaches the same. Frequent,
long, smooth dialysis is the best dialysis,
but our standard is infrequent, fast, and
insufficient.
It is self evident that daily dialysis, and
particularly long nightly dialysis, should be
the standard rather than the exception.
Absurdly, there are bureaucratic and payment
obstacles in the way of giving the
very best dialysis: payment for any dialysis
sessions over 3-per week has to be justified.
It should be the other way around. If
we do not dialyze our patients daily, some
explanation needs to be given for the substandard
care provided them. While we
should be proud of the fact that the USA
has led the way in liberal and humane
acceptance of dialysis patients — we
have truly been the Statue of Liberty
to them — we must now also strive to
achieve the best survival. 
