Possible Shunt Components; Tube Systems; Surgical Procedure - MIETHKE DUALSWITCH VALVE Instrucciones De Manejo

| INSTRUCTIONS FOR USE
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Fig. 6 Possible codes (top picture) and an X-ray image
of the DUALSWITCH VALVE (pressure ratings 13/30)
In case of questions or problems concerning
the valve functionality, please contact the me-
dical products advisors at Christoph Miethke
GmbH & CO. KG.

POSSIBLE SHUNT COMPONENTS

The DSV is available with different shunt acces-
sories. These variants are comprised of a vari-
ety of components, which are described briefly
introduced below:
The Borehole Reservoir is positioned in the
cranial borehole. It allows measuring the in-
traventricular pressure, injecting drugs and
extracting CSF. Its solid titanium base is highly
puncture-resistant. All reservoirs are available
with integrated catheters or connectors. A spe-
cial Borehole Reservoir is the SPRUNG RESER-
VOIR. As additional new feature of this reservoir
CSF can be flushed towards the valve because
of a one-way valve in the bottom of the reser-
voir. By this mechanism a flow in the direction
of the ventricular catheter is avoided during the
pumping procedure. The opening pressure of
the shunt system is not increased by the im-
plantation of the SPRUNG RESERVOIR.
The prechamber is positioned on the craniu m.
It allows measuring the intraventricular pressu-
re, injecting drugs, extracting CSF and perfor-
ming a palpatory ventricle inspection. Its solid
titanium base is highly puncture-resistant. A
puncture of the Prechamber or the CONTROL
RESERVOIR should be performed as perpendi-
cular to the reservoir surface as possible with
a cannula of max. 0,9 mm. 30 times of punc-
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tures are able without any restrictions. A special
Prechamber is the CONTROL RESERVOIR. As
an additional new feature of this reservoir, CSF
can be flushed towards the valve because of a
one-way valve in the proximal inlet of the reser-
voir. By this mechanism a flow in the direction
of the ventricular catheter is avoided during the
pumping procedure. The opening pressure of
the shunt system is not increased by the im-
plantation of the CONTROL RESERVOIR.
Warning note: Frequent pumping can lead
to overdrainage and thus to unphysiological
pressure conditions. The patient should be
informed about the risk.

TUBE SYSTEMS

The DSV has been designed to ensure the
optimal ventricular pressure. It is available
as a shunt system or as individual valve units
with or without an integrated distal catheter
(internal diameter 1.2 mm, external diame-
ter 2.5 mm). Individual valve units should be
used with catheters of approx. 1.2 mm inter-
nal diameter and approx. 2.5 mm external
diameter. The connector on the valve allows
using catheters of 1.0 mm to 1.5 mm inter-
nal diameter. The external diameter of the
catheter should be about double the internal
diameter. This rule does not apply where the
valve is used for lumboperitoneal drainage. In
this case, a lumbar catheter can be connected
to the valve or the reservoir, respectively. In any
case, the catheters must be carefully fixed, with
a ligature, to the valve connectors. Kinks in the
catheter have to be avoided. The provided ca-
theters have virtually no effect on the pressure-
flow characteristics.

SURGICAL PROCEDURE

Positioning the ventricular catheter
Several surgical techniques are available for po-
sitioning the ventricular catheter. The necessary
skin incision should be carried out, preferably,
in the shape of a lobule pedicled towards the
draining catheter or as a straight skin incision.
To avoid CSF leakage, care should be taken
that the dura opening is kept as small as possi-
ble after applying the borehole. The ventricular
catheter is stiffened by the introducing stylet
supplied with the product.
The DSV is available in different shunt variants:
When using a DSV SHUNTSYSTEM with Bo-
rehole Reservoir or SPRUNG RESERVOIR, the
ventricular catheter is implanted first. Once the
introducing stylet has been removed, the pa-
tency of the ventricular catheter can be tested
by checking if CSF is dripping out. The cathe-
ter is shortened and the Borehole Reservoir is
connected, with the connection secured with a
ligature. The skin incision should not be located
directly above the reservoir.
The DSV SHUNTSYSTEM with prechamber
or CONTROL RESERVOIR comes with a de-
flector. This deflector is used for adjusting the
position of deflection before implantation of the
ventricular catheter. The catheter is deflected;
the prechamber is put into place. The position
of the ventricular catheter should be inspected
again by postoperative CT or MR imaging.
Positioning a lumbar catheter
Presently, a lumbar catheter is not part of the
product range of Christoph Miethke GmbH &
CO. KG. The relevant manufacturer's instruc-
tions must be observed when using a lumbar
catheter.
Positioning the DSV
The mode of operation of the DUALSWITCH
VALVE depends on the body position of the pa-
tient. Therefore, care must be taken to ensure
that the connector axis is implanted parallel to
the body axis, as far as possible.
The implantation is performed subcutaneously,
either supraclavicular or just infraclavicular. The
valve is marked with an arrow pointing distally
(downward) to indicate the flow direction. The
valve is implanted flat in a subcutaneous po-
cket; the orientation of the labeling (towards
the skin or towards the ribs) does not affect the
valve functionality.
INSTRUCTIONS FOR USE |
Following the incision and the tunneling under
the skin, the catheter is either pushed from the
borehole to the chosen valve implantation site
or the other way round, depending on which
system is used. For lumboperitoneal drainage,
we recommend choosing the arcus costalis as
the implant position.
Warning note: The adjustable unit must
be placed over a hard boney surface and
should not be implanted within an area,
which makes finding and feeling the valve
more difficult (e. g. under a scar).
Frequent pumping can lead to overdrainage
and thus to unphysiological pressure condi-
tions. The patient should be informed about
the risk.
Positioning the peritoneal catheter
The access site for the peritoneal catheter is left
to the surgeon's discretion. It can be applied
e. g. para-umbilically in a horizontal direction
or transrectally at the height of the epigastrium.
Likewise, various surgical techniques are
available for positioning the peritoneal catheter.
We recommend pulling through the peritoneal
catheter, using a subcutaneous tunneling tool
and perhaps with an auxiliary incision, from the
shunt to intended position of the catheter.
The peritoneal catheter, which is usually secure-
ly attached to the DSV, has an open distal end,
but no wall slits. Following the exposure of, and
the entry into, the peritoneum by means of a
trocar, the peritoneal catheter (shortened, if ne-
cessary) is pushed forward into the open space
in the abdominal cavity.
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