Biomedical Engineering Reference
In-Depth Information
1.4.2
Plasma separation
Although successful treatment of, for example, Goodpastures syndrome with
plasma separation had been reported in the 1970s and plasma separation for
removal of larger toxins from human blood has been practised since at least the
1980s, it is still not a widespread and widely accepted treatment method. This is
mainly due to the absence of large controlled, randomised studies that prove the
effectiveness of plasma separation procedures. Although there are many smaller
studies and case reports that suggest that plasma separation can be an effective
treatment for a variety of diseases, there is still a lack of evidence.
33
Without
such evidence, reimbursement for these therapies can be achieved only in rare
cases, which limits plasma separation to a last resort treatment when all other
options have failed.
The potential cost for the payers, if plasma separation and treatment were
more widespread, is considerable. A bare plasma separation process was reim-
bursed in 2007 in the USA at US$720, therapies involving further separation
steps at more than US$1500.
34
Healthcare providers and payers are therefore in
a chicken-and-egg situation: as there is hardly any reimbursement, it is virtually
impossible to collect the evidence needed to support more widespread applica-
tion of blood plasma treatment. Without evidence-based recommendations and
good practice guidelines an approval for more liberal reimbursement cannot be
achieved, even if therapies based on plasma separation may in the end save
money due to their selectivity and efficiency. Without rising numbers of treat-
ments, the cost per procedure will remain high, which will again make payers
cautious to more liberally grant reimbursement. The reports about successful
treatments are increasing and medical societies and healthcare authorities around
the world are discussing plasma separation treatments more often. Before
systematic approvals can be given, however, medical professionals, societies
and providers have a long way to go.
1.5
Future trends
Perspectives for blood oxygenation membranes in cardiac surgery are rather flat:
cardiac surgery with the aid of an oxygenator is established as the gold standard
with excellent outcomes. Major changes to the procedure as such, to the
oxygenator or the oxygenation membrane, are not expected. Devices will
continue to become smaller with less priming volume and less surface area,
improved blood flows and better biocompatibility through optimised shear rates
and haemocompatible coatings. The basic principle of a microporous hydro-
phobic membrane in plastic housing is no matter of debate. Alternative treat-
ment methods have been established, such as off-pump cardiac surgery or
developments such as catheter interventions for heart valve replacement. The
decrease due to this competition has for some years already been compensated
