Philips Avalon FM20, Instructions For Use Manual

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Monitoring FHR Using DECG
FM30/50 This chapter describes how to monitor a single fetal heart rate via direct ECG (DECG), using a spiral
fetal scalp electrode in the intrapartum period.
Read and adhere to the instructions that accompany the fetal scalp electrode, the DECG
adapter cable, and the attachment electrode. Pay attention to all the contraindications,
warnings, and for the DECG adapter cable, the cleaning and disinfection procedures.
Before starting to monitor, first define the fetal position, and ensure that it is suitable for DECG
monitoring.
Misidentification of MHR as FHR
Confirm fetal life before monitoring, and continue to confirm that the fetus is the signal source for the
FHR during monitoring. Here are two examples where the MHR can be misidentified as the FHR
when using a fetal scalp electrode:
•
Electrical impulses from the maternal heart can sometimes be transmitted to the fetal monitor
through a recently deceased fetus via the spiral scalp electrode, appearing to be a fetal signal
source.
• The recorded MHR, and any artifact, can be misinterpreted as a FHR especially when it is over 100
bpm.
To reduce the possibility of mistaking the MHR for FHR, it is recommended that you monitor both
maternal and fetal heart rates (see “Monitoring Maternal Heart / Pulse Rate” on page 155). The
monitor's cross-channel verification (CCV) facility can help by automatically detecting when the same
heart rate is being recorded by different transducers.
What You Need
You can measure fetal DECG using the equipment combinations shown in the following illustrations.
WARNING
NEVER attempt to connect the fetal scalp electrode to anything other than the correct DECG adapter
cable.