Revision D 170 Series Monitor 5-5
2003023-001
Fetal Heart Rate Monitoring: Fetal Heart Rate Offset
Fetal Heart Rate Offset
The Model 172 monitors twins using dual ultrasound. The Model 173 (with only
one ultrasound channel) monitors twins using FECG and ultrasound. The Model 174
(with a combi-connector) can monitor twins using FECG/ultrasound or dual
ultrasound. When monitoring twins, overlapping fetal heart rate traces may be
difficult to interpret. Models 172, 173, and 174 provide a +20 BPM shift for the
secondary FHR trend to alleviate this problem.
Enabling/Disabling the Fetal Heart Rate Offset Mode
The fetal heart rate offset mode can be enabled/disabled from a service setup mode.
Refer to the “170 Series Service Manual” for more information.
NOTE: Enabled and active do not
mean the same thing. When the option
is enabled via the service mode, you
then have the capability to activate and
de-activate the function as needed.
The fetal heart rate offset mode has three settings:
disabled: users cannot activate the function.
enabled/on: users can activate/de-activate the function.
enabled/auto-revert: users can activate/de-activate the function; in addition, the
shifted trend automatically returns to the unshifted position after ten minutes.
Figure 5-2. Fetal Heart Rate Offset Example (Model 172 shown)
FHR
US2 + 20