Full text of DOI:10.1093/ndt/15.1.5

Nephrol Dial Transplant (2000) 15: Editorial Comments
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Nephrol Dial Transplant (2000) 15: 5–8
Haemodialyser reuse: facts and fiction
Jose´ Vinhas and Joao Pinto dos Santos
˜
Division of Nephrology, Hospital de S. Bernardo, Setu´bal and CHL Centro de Hemodia´lise do Lumiar, Lisboa, Portugal
with high-flux dialysers increased from 0.2% in 1993, to
8.1% in 1998. The present use of high-flux membranes
is 40% in Germany (Dr Bommer, oral communication),
20% in Holland (Dr Leunissen, oral communication),
10% in UK (Dr Hoenich, oral communication), 20% in
Spain (Dr Valderrabano, oral communication), and
20% in Italy [5].
High-flux high-price dialysis: is everybody using it?
Since the advent of haemodialysis, the number of
patients on haemodialysis has been growing constantly
and is now increasing by 7–9% annually. Simul-
taneously, over the years, there has been a trend towards
the use of high-flux dialysers which are much more
expensive than cellulosic low-flux dialysers, albeit at
different rates in different countries. In the US, the
number of patients treated by high-flux dialysis,
increased from 5% in 1987 to 31% in 1994. In 1994, the
proportion of patients treated by high-efficiency/high-
flux dialysis was 57% [1]. In 1996, in Japan, 43.5% of
the patients were treated with high-flux dialysis [2]. In
Australia, there has also been a movement towards
more biocompatible membranes. In 1997, the most
common membrane was hemophanB, used by 35% of
the patients and only 6% of the patients were treated
with high-efficiency/high-flux dialysers, mostly cellulose
triacetate [3]. What about Europe? Data from the 1993
EDTA Registry showed that 6.8% of patients in the
European Economic Community (EEC) were on high-
flux techniques [4]. However, great differences were
observed between countries, ranging from 0% in
Denmark, Finland, Ireland and Luxembourg, to 21%
in Italy. However, these figures probably do not reflect
the present use of high-flux dialysers in Europe. For
example, in Portugal, the number of patients treated
Reuse: a solution for the 1990s?
As the resources devoted to health care do not increase
at the same rate as the cost, strategies to reduce costs
are needed. Dialyser reuse has been one possible solu-
tion. In the US, because of a payment reimbursement
freeze since 1982, the movement towards high-flux
dialysis has been the rationale for a continued growth
in reuse, which in 1996 was practised by more than
81% of centres [6]. In Australia, in 1987, 35% of the
patients were treated with reprocessed dialysers [9],
but more recent data are not available. Whatever the
reason, Europe has shown quite a different trend.
According to 1992 EDTA–ERA Registry data [7], 9%
of the patients were treated with reprocessed dialysers,
but there were huge differences in the prevalence of
dialyser reuse. Dialyser reuse was not performed in
Austria, Denmark, Finland, the Netherlands and
Sweden. But reuse averaged 3% in Spain, 5% in
Germany, 6% in France, 10% in the UK, and 22% in
Belgium. The highest figures were in Portugal (77%),
Poland (88%), and Bulgaria (100%). However, since
then, three countries (Portugal, France and Spain)
have prohibited the practice of reuse, and in the EEC
Correspondence and offprint requests to: Jose´ Vinhas, MD, ChS,
Division of Nephrology, Hospital de S. Bernardo, R. Camilo Castelo
Branco, 2910–446 Setu´bal, Portugal.
E-mail: j.vinhas@mail.telepac.pt.

6
Nephrol Dial Transplant (2000) 15: Editorial Comments
reuse is not performed in 8 out of 15 states. The high-flux), and found that the mortality associated
practice of dialyser reprocessing will be debated in the with reuse practices was not consistently different from
near future by the EEC Commission in order to that associated with no reuse. The authors analysed
standardize legislation across all EEC states, and it is the 1989–1993 period, and showed that the reuse-
possible that a no-reuse policy will be decided for all associated mortality is not a generalized effect but,
EEC members [8]. Likewise, reuse is forbidden in rather, is very specific to provider characteristics and
Japan by health insurance regulations and cultural that the effect is not consistent over time. In the
preferences. Canada maintains an intermediate posi- 1989–1990 period, an adverse effect of peracetic acid
tion [10]: in 1992, 12% of the patients were treated was observed only in freestanding, for-profit dialysis
with reused dialysers. The most common number of units practicing manual reuse. In the 1991–1993 period,
reuses in Europe is 3, 6, or 9 [8], which is considerably the adverse association of peracetic acid was no longer
lower than that practised in the US where the average present. Furthermore, the investigators showed that
number is 16 [11], but sometimes reaching 192 [12]. the for-profit status of dialysis units adversely influ-
Who is heading in the right direction?
ences the outcome. Again, there was no data on dialysis
therapy, nutrition and the correction of anaemia, three
factors known to influence outcome. Recent studies by
National Medical Care [17], and from Dialysis Clinics
Inc [18], published only in abstract form, analysed the
Is dialyser reuse safe?
The safety of reuse has been questioned over the last outcome associated with reuse, adjusted for albumin
20 years with studies that show conflicting results. The levels and dialysis therapy, and found no difference
first report of the long-term impact of dialyser reuse on between reuse and no reuse.
mortality was published in 1987 by Held et al. [13] and
showed that patients treated with dialysers reprocessed
Facts and fiction
with formaldehyde had a 12% lower mortality than
Regarding reuse, some areas are a source of concern.
patients treated with dialysers that were not reprocessed.
No further outcome studies were published until
1994, when Held et al. [14] reported the results of Reuse is associated with an increased incidence of
a study of approximately 66 000 prevalent patients,
using Health Care Financing Administration (HCFA)
information on ESRD patient survival and Centers for
Disease Control and Prevention (CDC) information on
dialysis units’ dialyser reuse practices. This study, in the
main, delineated a 13% increase in mortality in patients
treated with dialysers reprocessed with peracetic acid,
and a 17% increase in mortality in patients treated with
dialysers reprocessed with glutaraldehyde but only in
freestanding units. No increased risk of death was found
for patients treated with dialysers reprocessed with
formaldehyde. Two years later, Feldman et al. reported
similar results. The authors studied a non-concurrent
cohort of 27 938 ESRD incident patients beginning
dialysis in the US in 1986 and 1987, and found a 10%
increase in mortality in freestanding facilities repro-
cessing dialysers with peracetic acid [15]. Nevertheless,
some inconsistencies were observed in these two studies.
Feldman et al. [14] did not find any increased mortality
in hospital units reprocessing dialysers with peracetic
acid or glutaraldehyde, and Held et al. [14], in a
preliminary analysis in hospital-based units, found a
10% decrease in mortality in hospital units reprocessing
dialysers with peracetic acid. These results suggest that
the increased mortality is not related to the type of
germicide used. The limitations of these studies included
the absence of patient-level data, namely, on dialyser
reprocessing, co-morbidity, quality of dialysis, nutrition
and the treatment of anaemia.
pyrogenic reactions
In the US, over the years, units that reprocess dialysers
were more likely to report pyrogenic reactions than
units that did not reprocess dialysers. From a historical
perspective, units that reprocess dialysers manually
had more pyrogenic reactions than those using auto-
mated systems [6,12]. However, CDC investigation
showed that many of these episodes were the result of
inadequate reprocessing procedures, such as the use of
low concentrations of the germicide and use of water
that did not meet the Association for the Advancement
of Medical Instrumentation (AAMI) standards (bac-
terial colony count <200 CFU/ml or bacterial lipo-
polysaccharide concentration <5 endotoxin units/ml)
as a result of design flaws in the water treatment and
delivery system and poor or non-existant monitoring
and maintenance practices [6,19]. Furthermore,
although data supporting the advantage of using more
stringent guidelines than those issued by AAMI are
not available, many believe that this might be neces-
sary. In this regard, the European Pharmacopoeia
guidelines for dialysate water are already more strin-
gent than US standards (bacterial colony count <100
CFU/ml and bacterial lipopolysaccharide levels less
than 0.25 endotoxin units/ml).
Polysulfone membranes reprocessed with bleach
are associated with increased protein loss
The impact of reuse practices and dialysis unit and
patient characteristics on mortality were studied by
Collins et al. [16], who studied a 10% random sample In a recent publication, Kaplan et al. [20] showed that
of period-prevalent haemodialysis patients from units repetitive bleach processing of high-flux polysulfone
practicing conventional dialysis (<25% high-efficiency/ dialysers increased permeability and caused substantial

Nephrol Dial Transplant (2000) 15: Editorial Comments
7
protein losses that were related to the frequency of patient survival. Clearly, this is an area that needs
reuse and were of considerable magnitude after the further investigation.
10th use. Other studies have shown similar results [21].
Is it acceptable to use this technique without limiting
the number of uses?
In summary, dialyser reprocessing is still a controver-
sial practice that is not without risks. Dialysis units
should establish a rigorous quality assurance pro-
gramme that includes the regular monitoring of the
quality of the water. At least, AAMI guidelines should
be followed, but it is possible that more stringent
recommendations will become standard. What will be
the dominant trend in the future? A movement towards
no reuse which is the highest possible safety or a
movement towards a continued growth in reuse under
increasing economic pressure?
The impact of haemodialyser reuse on mortality is
still an area of concern that needs further investigation.
Ironically, it is possible that, in the meantime, there
will be a trend towards no reuse under the pressure of
dialyser manufacturers, which own increasing numbers
of dialysis units.
Total cell volume (TCV) reuse criterion is not a
well-founded practice
Worldwide, the currently accepted standards for the
practice of reuse of dialysers are those issued by the
AAMI. The only quantitative criterion recommended
by AAMI is that the TCV should not fall bellow 80%
of its original value, assuring that the urea clearance
of the dialyser stands within 90–110% of the original
level [22].
Is this a well-substantiated statement? Unfortu-
nately, the answer is no. It is based only on an early
study by Frank Gotch [23], which was made with a
small sample of cellulosic low-flux dialysers, repro-
cessed manually with formaldehyde and operated at
low blood flow rates (Qb 200 ml/min). Moreover, no
rigorous statistical analysis of the confidence intervals
was performed. No other subsequent publication has
presented data establishing the validity of using 80%
of the initial TCV as the criteria for acceptable dialyser
reuse [24]. Is this not an important issue? Does anyone
want to hold the position that the only important issue
is the monthly monitoring of the delivered dose of
dialysis, quantified by the removal of small solutes
(Kt/V or URR)?
References
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surveillance of dialysis associated diseases in the United States—
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2. Shinzato T, Nakai S, Akiba T et al. Report on the annual
statistical survey of the Japanese Society for Dialysis Therapy
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outcomes
Has reuse an effect on middle-sized molecule removal?
Recent studies [25–27] have shown that dialyser repro-
cessing with RenalinB does not restore the original b2-
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