Answers Explained
Ifzfetalzarterialzpressurezbeginsztozfallzbelowznormalzlevels:z-zCORRECTzANSWER-
A.zBARORECEPTORSzCAUSEzVASOCONSTRICTIONzANDzINCREASEzTHEzFHR
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atezviazthezparasympatheticzvagusznerve.zAzdecreasezinzarterialzpressurezresultszinzanzincreasedzheartzrate
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Source:zhttps://perigen.com/what-regulates-fetal-heart-rate/
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placentalzcirculation
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Anzincreasezinzthezfetalzheartzratezimmediatelyzprecedingzazvariablezdecelerationziszcausedzby:z-
zCORRECTzANSWER-Occlusionzofzthezumbilicalzvein
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hiszpatternzoftenziszobservedzaszazshoulderzonzthezFHRzmonitorzstripzimmediatelyzbeforezthezabruptzvaria
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Source:zhttps://www.glowm.com/section-
view/heading/Intrapartum%20Fetal%20Monitoring/item/202#
WhenzassessingzazFHRztracing,zthezfirstzstepzisztoz-zCORRECTzANSWER-Estabilishzthezbaselinezrate