
22
Unstable fetal heart rate display
a. Fetus is too young. Wait a few weeks before trying the test
(
Elite
200, 200R).
trying the test again, or try a manual method for determining heart
rate.
b. Fetus is moving. Wait a few minutes to see if the fetus
settles down.
c. Excessive static. Some probe movement patterns may
cause erroneous heart rate displays. Refer to the above
section on static for recommendations.
d. Probe is detecting blood flow sounds. Reposition the probe.
Inaccurate fetal heart rate display
a. The detected signal is maternal or maternal mixed with fetal sounds.
A (
Elite
200, 200R).
maternal sound, usually one half of the fetal sound, may produce
harmonics which are in the fetal range. Reposition the probe to
detect only fetal sounds.
b. Excessive static. Some probe movement patterns may cause
erroneous heart rate displays. Refer to the above section on static
for recommendations.
c. Fetal heart rate is out of the display range. Harmonics may cause
doubling of the displayed fetal heart rate.
Audible hum or feedback with
a. Replace or recharge battery.
no signal present.