XVIVO Perfusion System (XPS
TM
) Instructions for Use
-
8
-
P/N: 9182
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0189 Revision Q
The primary mode of action for
STEEN Solution
™
is its ability to
provide optimal colloid
-
osmotic
pressure (COP), permitting stable
fluid compartment homeostasis for
sufficient time to allow meaningful
functional evaluation of the lung at
37°C. STEEN Solution
TM
therefore
mimics the
in vivo
situation with-
out the risk of edema formation in
the absence of harmful pro
-
inflammatory cytokines and
activated leucocytes associated
with trauma, stress and brain
death. This mode of action is
primarily related to the water
binding properties of albumin and
its distributions across semi
-
permeable membranes between
the intra
-
and extra
-
vascular spac-
es within the lung, and is not
based on any metabolic or
pharmacological action of either
colloid.
1.1 GENERAL OVERVIEW
STEEN Solution
™
is a clear, sterile, non
-
pyrogenic, non
-
toxic physiological
salt solution containing human serum albumin (HSA) and dextran 40. This
solution is an extracellular (low potassium) electrolyte solution with physio-
logical colloid
-
osmotic pressure (COP) designed for use as a temporary con-
tinuous normothermic machine perfusion solution for assessment of initially
unacceptable isolated lungs after removal from the donor in preparation for
eventual transplantation into a recipient.
The composition of STEEN Solution
™
was
designed to simulate the colloid
-
osmotic
pressure (COP) and crystalloid
-
osmotic
properties of human plasma to permit safe,
continuous
ex vivo
lung perfusion at
normothermia for up to 6 hours without the
development of either tissue edema or de-
hydration
-
i.e. the COP and osmotic pres-
sure of the solution were chosen to maintain
optimal water balance between the cellular
and the intra
-
and extra
-
vascular spaces.
The optimal (iso
-
oncotic) COP is provided by
a proprietary combination of human
albumin and dextran 40.
The electrolyte
composition is essentially extra
-
cellular
(low K+) with a phosphate buffer.
STEEN Solution
™
is intended to be used with the XVIVO Perfusion System
(XPS
TM
)
for flushing and temporary continuous normothermic machine
perfusion of initially unacceptable excised donor lungs during which time
the function of the lungs can be reassessed for transplantation. The time
required by the lungs to reverse the negative effects of neurogenic
pulmonary edema and to achieve a normal fluid balance can vary based on
the initial donor environment.
Typically, the duration of normothermic machine perfusion lasts 3
-
5 hours
(per FDA PMA approval) 3
-
6 hours (per FDA Novel Extension Study and CE
approval) to allow the lungs to slowly warm up, normalize fluid balance and
be effectively assessed. In exceptional cases, an additional 1
-
2 hours may
be needed for the lung to be adequately reassessed to allow assessment for
transplantation suitability:
1
STEEN Solution
TM
5 hr (FDA)
6 hr (Novel Extension / CE)
3
-
5hr (FDA)
3
-
5 hr (Novel Extension) / CE
2 hr
1 hr
30
min
2 hr
1 hr
30
min