MIETHKE proGAV 2.0 Mode D'emploi page 20

| INSTRUCTIONS FOR USE
GB
of the instrument. The desired pressure setting
must point on the scale in direction of the in-
let connector and the ventricular catheter. By
applying light pressure the rotorbrake will be
released and the pressure of the proGAV 2.0
can be changed.
a)
b)
Fig. 12: a) and b)
Adjustment with the proGAV 2.0 Adjustment Tool
The proGAV 2.0 is equipped with a feedback-
mechanism. When using the proGAV 2.0 Ad-
justment Tool, pressure on the housing of the
valve is created and a resulting acoustic signal
(a clicking sound) is produced due to the unique
construction of the valve housing. This clicking
sound indicates that the rotorbrake is released.
Now the rotor can rotate freely. Once the pres-
sure on the valve is released, a clicking sound is
heard and the rotorbrake is again locked safely
so that the valve is safe against spontaneous
re-adjustments.
The clicking sound is well recognizable before
implantation. However after implantation, once
the valve is filled up, depending on place and
texture of the surrounding area of the implant,
the acoustic signal could be considerably mut-
ed. The clicking sound should generally be au-
dible by the patient itself or via a stethoscope.
20
Caution: The new opening pressure set-
ting of the valve must not differ from the
measured opening pressure by more than
8 cmH O in any one setting (see chapter 4
2
"verifying the adjustment").
Example: Opening pressure is to be changed
from 3 to 18 cmH
O. With only one adjustment
2
procedure the rotor would turn in the wrong
direction (short way) and would stop at the po-
sition 0 cmH O. The correct adjustment is in 2
2
steps: Adjustment from 3 to 11, and from 11 to
18 cmH O. The rotor turns correctly.
2
3
0
18
a)
Fig. 13: Rotor rotation during adjustment
a) false b) correct
Caution: From proGAV 2.0 Adjust-
ment Tool a magnetic field ema-
nates. Metallic objects and magnetic
media storages should have a sufficient
safety margin.
4.Verifying the adjustment
After adjusting the valve by using the proGAV
2.0 Adjustment Tool, it must be verified using
the proGAV 2.0 Compass as described in step
2. If the measured pressure now differs from the
intended pressure level, the adjustment proce-
dure has to be repeated from step 3.
Due to postoperative swelling of the skin the
adjustment of the valve setting may be difficult
within the first few days.
If the pressure configuration of the valve cannot
be determined with complete certainly by the
proGAV 2.0 Compass, the use of imaging tech-
niques is recommended.
proGAV 2.0
3
0
18
b)