Determine the location of the second fetal signal using palpation or a fetoscope.
Attach the buckle of the ultrasound transducer to the belt. Apply aquasonic coupling gel to the face
of the transducer. Place the second ultrasound transducer on the abdomen over fetal site and move
it slowly until the characteristic hoof-beat sound of the fetal heart is heard.
The fetal heart rate value FHR2 will be shown on the screen. At the same time, the ultrasound
wave will be drawn in yellow color on the screen.
CAUTION: Do not mistake the higher maternal heart rate for fetal heart rate
.
4
Monitor Adjustments:
Adjust the position of ultrasound scanner according to the need.
There is only one fetal heart sound can be heard from the speaker, change it by selecting different
channel of fetal heart sound (the first sound channel for FHR1, and the second sound channel for
FHR2)
Readjust the volume setting for the desired loudness.
Note:
The ultrasound transducer measures the FHR; the misuse of it will be result in wrong
measurement or misunderstanding of it. So it requires the doctor pay attention to it:
①
The best quality records will only be obtained if the transducer is placed in the optimum
position.
②
Positions with strong placental sounds (swishing) or fetal cord pulse (indistinct pulse at
fetal rate) should be avoided.
③
If the fetus is in the cephalic position and the mother is supine, the clearest heart sound
will normally be found on the midline below the umbilicus. During monitoring prolonged
lying in the supine position should be avoided owing to the possibility of supine hypotension.
Sitting up or lateral positions are preferable and may be more comfortable to the mother.
④
It is not possible to FHR unless an audible fetal heart signal is present. The fetal pulse can
be distinguished from the maternal pulse by feeling the mother’s pulse during the
examination.
⑤
During the monitoring, the doctor should observe the monitor screen, if the screen break
off frequently, the position of the ultrasound transducer may had out of proper position due
to the moving of the fetus.
⑥
During the monitoring, if the FHR can be heard without steadily sound of the fetal heart,
it may not proper positions. So move it slowly until the proper position is found. But if it is
not found, the doctor should do other examination, to observe if the fetus is normal.
5.1.2 Monitoring Contractions
Operation Procedure:
1
Preparing the Monitor
Turn the monitor on and verify that the normal monitoring screen appears on the display.
Insert the TOCO Transducer into the socket.
