GE b30, User'S Reference Manual

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B30 Patient Monitor
14-4
Starting with accurate values
Pressure transducers generally produce a small signal even when no pressure is applied to
them. It is necessary to zero the monitor with the transducer to establish an accurate electrical
zero point.
Also, the position of the transducer effects the accuracy of the measurement. An error of 10
mmHg of static pressure is introduced for every 13.6 cm (5.4 inches) difference in height
between the mid-heart and the transducer.
To zero the transducer, open the transducer to air and do one of the following:
•
Press the
Zero Px
module key or the
Zero ALL
side panel key. This starts zeroing
immediately.
NOTE: Selecting Zero ALL does not zero ICP. Zero it separately.
•
Press the
Invasive Pressures
key on the Command Board and select Zero Pressures .
During the zeroing process, the message ‘Zeroing’ is displayed. After the transducer is zeroed,
the message ‘Zeroed’ is displayed in the digit field. After each channel is zeroed, the time of
zeroing is displayed in the menu.
NOTE: Check zero level after power interruptions.
NOTE: Invasive pressures need to be zeroed after reconnecting the pressure
transducer or cable, and whenever the patient’s position is changed. If all channels
have not been zeroed, the message ‘InvBP not zeroed’ appears. However, the alarms
advance to yellow and red levels regardless of zeroing.
Invasive
Pressures