QUESTIONS & A+ GRADED ANSWERS
1. If fetal arterial preceding a vari- able deceleration is
pressure caused by:
begins to fall
below nor- mal
levels:
2. Which of the
fol- lowing is
an ex- trinsic
influence on
the FHR?
3. Fetal heart
rate vaiability
is definded as
fluc- tuations
in the baseline
that are
irregular in
4. The most
high- ly
oxygenated
blood in fetal
cir-
culation is
carried by:
5. An increase in
the fetal heart
rate
immediately
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, AWHONN Intermediate Fetal Monitoring Exam
QUESTIONS & A+ GRADED ANSWERS
A. BARORECEPTORS CAUSE n
VASOCONSTRICTION AND
INCREASE THE FHR
An increase in arterial blood
pressure produces vessel
distension and causes AMPLITUDE and FREQUENCY
arterial baroreceptors to
send neuronal messages to
the cardioinhibitory center,
which in turn causes rapid
slowing of the fetal heart rate
via the parasympathetic
vagus nerve. A decrease in Ductus venosus
arterial pressure results in
an increased heart rate.
Source:
https://per
Occlusion of the umbilical vein
igen.com/
The etiology of variable decelerations is likely related to umbilical
what- venous and arterial occlusion. Initially, with occlusion of the thin-walled
umbilical vein, venous return to the fetal right atrium is reduced, producing a
regulates-
reflex tachycardia. This pattern often is observed as a shoulder on the
fetal- FHR monitor strip immediately before the abrupt variable FHR
deceleration
heart-rate/
Fetal-
placental
circulatio
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