Mindray PM-9000, Operation Manual

Page: 261 / 378

IBP Monitoring
15-27
15.6.6.2 Troubleshooting
Trouble Cause Solution
When you inject air
to zero and calibrate
the device, the
baseline reappears
with the waveform
displayed. The catheter or tip is cut and
cannot hold zero for a long
time. The readings are unreliable. Remove
the ICT/B and use a spare. The
waveforms will be displayed
correctly.
The monitor
indicates ‘damaged
gauge’ or ‘over
range’. No matter
you inject air or not,
you cannot see the
waveform. Either the tip is ‘wedged’ or
the tip sensor was
over-pressured against the dura
during insertion. Therefore the
monitor detects a transducer
that has a very high initial zero
and finds this zero out of its
range. If the tip is wedged, pull back a few
millimeters to free it. This will allow
the monitor to be zeroed. If the above
action does not help, the transducer
must have been damaged. Remove the
transducer and return it the
manufacturer for repair.
Sometimes raising the scale of the
monitor requires a high zero offset.
Try raising the pressure scale to 90,
120 or 300mmHg and then zero. This
solution may work but the waveform
resolution will be compromised. It is
recommended to return the catheter
for repair when the measurement is
finished.
When everything
runs normally, the
‘damaged gauge’ or
‘over-range’ light
suddenly starts
flashing. Although over-pressured or
wedged, the sensor zero must
have been just within the range
of the monitor. As conditions
changed, the total pressure
(=zero ICP) pushed
the monitor beyond its
measurement range. Try raising the pressure scale to 90,
120 or 300mmHg and then zero.
The transducer can
be zeroed and we
have good pressure
waves, but the ICP
reading always
remains around zero
mmHg. The sensor face must be flat
(planar) against the dura. If its
facing the inner table of the
skull, you will get pressure
waves and be able to zero it
but not obtain actual ICP
readings.
The sensor may be placed
It is important that the transducer face
be placed against an intact section of
dura.
If required, use a contralateral burr
hole.