NCC EFM EXAM QUESTIONS AND VERIFIED ANSWERS
EFM paper speed
3cm/ minute
Ultra sound (EFM)
US transducer detects motion through ultrahigh frequency sound waves - it determines
FHR by auto correlation compares successive reflected ultra sound waveforms at many
points
FSE
fetal scalp electrode (ISE) measures interval between R waves
Value of EFM
used as a screen test, not considered diagnostic - normal EFM tracing = grater than
99% chance fetus with not have neurologic injury
Normal FHR pattern detects what?
Intact CNS, oxygenation of the brainstem, ANS and intact heart
sympathetic nervous system
FHR regulation, develops 1st in the fetus.
Release of norepinephrine/ epinephrine = increase in FHR
parasympathetic nervous system
FHR regulation
Release acetylcholine = a decrease in FHR (vagal)
*** responsible for producing variability as the fetus matures
- variability requires a mature neuro system
Baroreceptors
stretch receptors - respond to changes in BP =
-Abrupt decrease in FHR
-abrupt decrease in CO2
, -abrupt decrease in BP
** variable decelerations w/ moderate variability are baroreceptor influenced
Chemoreceptors
Respond to changes in o2,co2, and pH levels
When blood flow is below threshold for normal respiratory gas exchange, increase in
PCO2 stimulates Chemoreceptors to slow FHR
increase in PCO2, Decrease in O2, decrease in pH = vagal response (decrease in HR
in response to hypoxemia)
category 1 tracing
Normal - strongly predictive of normal acid base status at the time of observation
- baseline 110-106
-moderate variability
- absence of late decelerations
- absence of variable decelerations
- early decelerations can be present
Category 2 tracing
indeterminate - not predictive of abnormal acid base status however there are
insufficient data to classify as category 1 or 3.
category 3 tracing
Abnormal - predictive of abnormal acid base3 status at the time of observation
- absent variability AND any of the following
- Recurrent late decelerations
- recurrent variable decelerations
- Bradycardia
-sinusoidal pattern
Intention of FHR monitoring
** TO ASSESS FETAL OXYGENTATION**
EFM paper speed
3cm/ minute
Ultra sound (EFM)
US transducer detects motion through ultrahigh frequency sound waves - it determines
FHR by auto correlation compares successive reflected ultra sound waveforms at many
points
FSE
fetal scalp electrode (ISE) measures interval between R waves
Value of EFM
used as a screen test, not considered diagnostic - normal EFM tracing = grater than
99% chance fetus with not have neurologic injury
Normal FHR pattern detects what?
Intact CNS, oxygenation of the brainstem, ANS and intact heart
sympathetic nervous system
FHR regulation, develops 1st in the fetus.
Release of norepinephrine/ epinephrine = increase in FHR
parasympathetic nervous system
FHR regulation
Release acetylcholine = a decrease in FHR (vagal)
*** responsible for producing variability as the fetus matures
- variability requires a mature neuro system
Baroreceptors
stretch receptors - respond to changes in BP =
-Abrupt decrease in FHR
-abrupt decrease in CO2
, -abrupt decrease in BP
** variable decelerations w/ moderate variability are baroreceptor influenced
Chemoreceptors
Respond to changes in o2,co2, and pH levels
When blood flow is below threshold for normal respiratory gas exchange, increase in
PCO2 stimulates Chemoreceptors to slow FHR
increase in PCO2, Decrease in O2, decrease in pH = vagal response (decrease in HR
in response to hypoxemia)
category 1 tracing
Normal - strongly predictive of normal acid base status at the time of observation
- baseline 110-106
-moderate variability
- absence of late decelerations
- absence of variable decelerations
- early decelerations can be present
Category 2 tracing
indeterminate - not predictive of abnormal acid base status however there are
insufficient data to classify as category 1 or 3.
category 3 tracing
Abnormal - predictive of abnormal acid base3 status at the time of observation
- absent variability AND any of the following
- Recurrent late decelerations
- recurrent variable decelerations
- Bradycardia
-sinusoidal pattern
Intention of FHR monitoring
** TO ASSESS FETAL OXYGENTATION**
