Fetal Heartrate Monitoring (Moulton) Flashcards
Between external and internal monitoring, which will provide the most accurate tracings?
Internal
With an uncomplicated pregnancy, continuous external monitor should be done every ____ minutes in the active phase of first stage of labor.
Monitor every ____ minutes in second stage of labor.
1) 30
2) 15
With a complicated pregnancy, continuous external monitor should be done every ____ minutes in the active phase of first stage of labor.
Monitor every ____ minutes in second stage of labor.
1) 15
2) 5
With external electronic fetal monitoring, ____ is placed on maternal abdomen overlying the fetal heart and it records reflected sound waves from the fetal
heart back to the transducer.
Doppler ultrasound transducer
With external electronic fetal monitoring, a pressure sensitive tocodynamometer transducer detects and records frequency of __1__.
It does NOT measure the __2__.
1) Contractions
2) Strength of contraction
Rate is computed from the R wave peaks of
the fetal echocardiogram with what internal electronic fetal monitoring device?
Fetal scalp electrode
Fetal scalp electrode should be avoided in patients with?
HIV
What internal electronic fetal monitoring device gives precise measurement of the intensity of the uterine contractions in millimeters of mercury?
Intrauterine pressure catheter
Fetal Heart rate is determined by the?
Atrial pacemaker
Modulation of the rate occurs physiologically through innervation of the heart by the __1__ (decelerator) and __2__ (accelerator) nerves.
1) Vagus
2) Sympathetic
A fetus whose oxygen supply is marginal cannot tolerate the stress of ____ and will become hypoxic.
Contractions
Hypoxia, when severe, will result in anaerobic metabolism, resulting in the accumulation of pyruvic and lactic acid resulting in fetal __1__.
pH of fetal scalp blood normally is between __2__.
pH < __3__ is considered abnormal.
1) Acidosis
2) 7.25-7.30
3) 7.20 (fetal acidosis)
With each contraction, blood flow from the mother to the baby initially ceases as the ____ are compressed.
Uterine myometrial vessels (arteries and veins)
With a fetal monitoring strip, the upper tracing monitors?
The lower tracing measures?
Each small box equals how many seconds?
Dark line to dark line equals?
1) FHR
2) Uterine contractions
3) 10 seconds
4) 1 minute
Normal uterine activity is characterized by __1__ contractions or less in __2__ minutes, averaged over a 30 minute window.
If there are more contractions than this in the same time period it is termed __3__?
1) 5
2) 10
3) Tachysystole
With a fetal monitoring strip contractions can be measured from?
Peak to peak
What are Montevideo units?
What should they be at for a 2 hour period?
1) Sum of the contractions in a 10 minute period
2) Greater than 200
__1__ are calculated from readings of intrauterine pressure catheter by subtracting baseline from peak contraction for each contraction during a 10-minute window and adding the pressures.
The uterine contraction pattern should exceed __2__ units for at least 2 hours.
1) Montevideo units
2) 200 Montevideo
What is the range for a normal FHR?
Tachycardia is defined as?
Bradycardia is defined as?
1) 110-160 bpm
2) > 160 bpm
3) < 110 bpm
What is a late sign of hypoxia?
What is an early sign of hypoxia?
1) Bradycardia
2) Tachycardia
Maternal hypotension will result in?
Maternal fever will result in?
1) Bradycardia
2) Tachycardia
What is the most common cause of fetal tachycardia?
Chorioamnionitis
__1__ produce tachycardia in response to hypoxia.
__2__ influence FHR via the vagus n. in response to changes in fetal blood pressure.
1) Chemoreceptors
2) Baroreceptors
Baseline variability is due to fluctuations in the baseline FHR that are irregular in amplitude and frequency. Variability is visually quantified as the amplitude of __1__ in bpm of change in baseline rate.
Absent variability is when the amplitude range is __2__.
Minimal variability is when the amplitude range is __3__.
Moderate (normal) variability is when the amplitude range is __4__.
• Marked variability is when the amplitude range is __5__.
1) Peak-to-trough
2) Undetected
3) <5 bpm
4) 6-25 bpm
5) > 25 bpm
1) Decreased variability is an indicator of?
It is associated with __2__ and __3__.
1) Possible fetal stress
2) Hypoxia and acidemia
Prematurity, maternal fever, fetal tachycardia, maternal hyperthyroidism, and maternal substance abuse are all potential causes of ____ baseline variability.
Decreased
FHR may vary with uterine contractions by slowing or
accelerating. These responses are categorized as?
No change, acceleration, and deceleration
What type of FHR change is characterized by the FHR maintains the same characteristics as in the preceding baseline FHR?
No change
What type of FHR change is characterized by an abrupt increase in the FHR and is a normal reassuring response?
Acceleration
Acceleration at 32 weeks or greater is defined as heart rate of greater than or equal to __1__ bpm above baseline for __1__ sec or more (but less than 2 minutes).
Acceleration at less than 32 weeks is defined as heart rate of greater than or equal to __1__ bpm above baseline for __1__ sec or more (but less than 2 minutes).
1) 15 bpm
2) 15 seconds
3) 10 bpm
4) 10 seconds
Prolonged acceleration of FHR is defined by these changes lasting greater than?
There is a change in baseline if the acceleration how many minutes or more?
1) 2 minutes
2) 10 minutes
Spontaneous fetal movement, scalp stimulation or vibroacoustic stimulation, and vaginal examination are all causes of?
Acceleration
What type of FHR change is characterized by the FHR decreasing in response to uterine contractions?
These changes may be subclassified as?
1) Decelerations
2) Early, variable, late
Early decelerations are secondary to __1__?
This causes an increase in __2__?
Which then leads to a decrease in __3__.
Causing the activation of the central __4__ nerve.
This activation produces a decrease in __5__.
Recovery occurs as __6__ is relieved.
1) Head compression
2) Increased intracranial pressure
3) Cerebral blood flow
4) Vagus
5) Heart rate
6) Pressure
The __1__ of the deceleration occurs at the same time as the __2__ of the contraction and thus is a “mirror image”.
1) Lowest point
2) Peak
Variable decelerations are secondary to __1__?
The abrupt decrease in FHR can occur before, during, or after __2__ starts.
1) Umbilical cord compressions
2) Contraction
Variable decelerations is characterized by a decrease in FHR of > __1__ bpm lasting >15 sec and lasting < 2 minutes in duration.
1) 15 bpm
2) 15 seconds
If the umbilical cord is only slightly compressed, this will obstruct the __1__ which returns re-oxygenated blood to the fetal heart.
The initial normal fetal response to this is a slight __2__ in fetal heart rate to compensate for the lack of blood return and the slowly diminishing oxygen supplies.
If this slight __2__ in FHR is followed by a major drop in FHR, this phenomenon is called a “__3__.”
1) Umbilical vein (low pressure system)
2) Increase
3) Shoulder
Which deceleration is the most ominous deceleration?
Late decelerations
Late decelerations are caused by?
Uterine placental insufficiency
Repetitive late decelerations usually indicate fetal __1__ and __1__.
The low point of the deceleration occurs __2__ the peak of the contraction.
1) Metabolic acidosis and low arterial pH
2) After
Prolonged decelerations is defined as a decrease in FHR from baseline that is greater than or equal to __1__ bpm lasting more than __2__ minutes but less than 10 min.
1) 15 bpm
2) 2 minutes
Prolonged decelerations is commonly seen during?
Maternal pushing
Smooth, sine wave-like undulating pattern in FHR baseline with a cycle frequency of 3-5 per minute is characteristic of?
It is seen with?
1) Sinusoidal pattern
2) Fetal anemia
Amnioinfusion is the process of instillation of normal saline to alleviate?
This can eliminate what problem?
1) Cord compression
2) Variable decelerations
1) When the scalp is stimulated, if an acceleration of 15 bpm lasting 15 seconds occurs the fetal pH value almost always is?
This is especially useful to differentiate fetal sleep from __2__, when the fetal tracing shows reduced variability but no decelerations.
1) 7.22 or greater
2) Acidosis
The American Academy of Pediatrics (AAP) and the American College of Obstetricians and Gynecologists (ACOG) recommend how long from decision‐to‐incision for emergency caesarean delivery?
30 minutes
Electronic Fetal monitoring does NOT result in reduction of?
Cerebral palsy
