Chapman ch 9. FHR Assessment

Question 1

Three requirements for fetal heart rate interpretation

Answer 1

Baseline. Interpretation of episodic and periodic changes of fetal heart rate. Interpretation of uterine activity.

Question 2

IUPC

Answer 2

Intrauterine pressure catheter.

Question 3

Causes of decreased fetal oxygen supply

Answer 3

Reduction of blood flow through maternal vessels/hypertension, PIH

Reduction of oxygen via maternal blood such as the mom holding the breath, baby lying on vena cava.

Alterations in fetal circulation such as baby on cord, decreased blood flow to the placenta, hemorrhage, deterioration of the placenta

Reduction in blood flow to the placenta

Question 4

Reassuring FHR Pattern

Answer 4

Baseline should be 120 - 160. Accelerations with fetal movement. Should have moderate variability.

Question 5

Normal uterine activity in labor

Answer 5

Contractions every 2 to 5 minutes, lasting less than 90 seconds, intensity less than 80, relaxation 20 or less, the average pressure is 50 to 85

Question 6

Fetal compromise

Answer 6

Associated with fetal hypoxemia. Can lead to fetal hypoxia.

Question 7

Hypoxemia

Answer 7

Deficiency of oxygen

Question 8

Hypoxia

Answer 8

In adequate oxygen

Causes a release of epinephrine and norepinephrine to increase fetal heart rate and blood pressure

Question 9

Nonreassuring fetal heart rate patterns

Answer 9

Progressive increase or decrease in the baseline

Tachycardia/above 160

Decrease in variability

Severe variable deceleration’s equals less than 60, and lasting longer than 30 to 60 seconds

Late decelerations/not good with repetition or uncorrectable

Absence of variability/no movement

Prolonged deceleration/greater than 60 to 90 seconds

Severe bradycardia/less than 70

Question 10

Intermittent auscultation

Answer 10

Done with an ultrasound fetoscope, stethoscope, it DeLee/Hills fetoscope

Question 11

Leopold’s maneuvers

Answer 11

Know how to spell

Assesses fetal position to get the best PMI/point of maximum impulse

Question 12

Procedure for auscultation

Answer 12

Leopold’s maneuver’s
Place listening device over PMI
Palpate abdomen between contractions
Count maternal pulse while listening to fetal heart rate
Count fetal heart rate for 30 to 60 seconds
Auscultate fetal heart rate during contraction and 30 seconds afterwards to see how baby is responding

Question 13

Internal fetal monitoring

Answer 13

Membranes must be ruptured
Cervix sufficiently dilated about 2 cm
Presenting Part low enough to place electrodes

Question 14

Fetal tachycardia

Answer 14

Baseline above 160 that lasts for at least 10 minutes
Moderate =161-180
Marked 180+
Early sign of fetal hypoxemia
If heart rate persists from 200 to 220 fetal death may occur

Causes on the fetal side could be infection, drugs, chronic hypoxemia, Stimulation, compensation for hypoxemia, cardiac abnormalities, anemia.
Causes from the maternal side could be a anemia, hyperthyroidism, dehydration, fever, ChorioAmnionitis (infection uterus), anxiety, medications, drugs

Question 15

Bradycardia

Answer 15

Baseline below 110 that lasts at least 10 minutes
Less than 100 is a later sign of hypoxia
Occurs before fetal death
May be tolerated if it remains about 80 with variability
Moderate 110-119
Marked 100-

A decreased fetal heart rate leads to decreased cardiac output causes a decrease in umbilical bloodflow leads to decreased oxygen to the fetus causing hypoxia

Bradycardia with variability maybe benign. Bradycardia with a loss of variability or late decelerations is associated with impending hypoxia

Question 16

Maternal supine hypotensive syndrome

Answer 16

Caused by uterine pressure on the vena cava, decreases bloodflow return to heart, reduces cardiac output and blood pressure, decreases fetal heart rate causing bradycardia.

Treat by turning the mom on the right side, and rise slowly.

Question 17

Variability of fetal heart rate

Answer 17

One of the most reliable indicators of fetal health and oxygenation, confirms no metabolic acidosis. Shows irregular fluctuations in the baseline, short-term is Beat to beat. long-term is rhythmic waves or cycles from the baseline.

Question 18

Four ranges of variability

Answer 18

Absent or undetected: the amplitude range is undetectable, looks like a flatline

Minimal: not more than five bpm
Moderate: 6-25 from peak to trough
Marked: greater than 25bpm

If absent, turn mom to right side, Adjust the straps, give ice chips, no longer than 30 minutes. Fetus could be asleep or premature.

Question 19

Nervous system on fetal heart rate

Answer 19

Sympathetic increases it, responsible for long term variability, can be stimulated during hypoxemia.
Parasympathetic decreases it
Head compression stimulates the Vagus nerve causes a decrease.

Question 20

Accelerations

Answer 20

An abrupt increase above baseline
It’s a good thing predictive of good O2.
15 bpm or greater, last 15 seconds or more
Returns to baseline within two minutes from start
Periodic or episodic
Periodic are caused by the sympathetic nervous system or usually a breech presentation
Episodic occur during fetal movement and indicate fetal well-being

Require no interventions.

Question 21

Decelerations

Answer 21

Periodic changes that last from a few seconds to no longer than two minutes.
Caused by the parasympathetic and they are either benign or nonreassuring
Described by relation to onset and the end of contraction and shape
Early, late, or variable
Recurrent occur with at least 50% of the contractions over a 20 minute.
Intermittent are with less than 50% of the contractions over 20 minutes

Question 22

Early decelerations

Answer 22

Gradual decrease and return to baseline during contraction. Caused by head compression. Normal and usually benign. Uniform shape that mirrors contraction. Usually during the first stage while 4 to 7 cm dilated and also during the second stage during pushing
NADIR is the lowest point of deceleration
No intervention is needed

Question 23

Late decelerations

Answer 23

Sign on fetal intolerance to labor. Cause by uteroplacental insufficiency such as a smoker or cocaine user. Also caused if the placental cord is compressed. Gradual decrease and return to baseline usually after a contraction. Nadir is after peak of contraction. Returns after the contraction is over.

Question 24

Indications of late decelerations

Answer 24

Presence of fetal hypoxemia/insufficient placental perfusion. Fetal hypoxemia progressing to hypoxia. Acidemia progressing to acidosis.

*** Ominous when uncorrectable, especially with variability and tachycardia. Turn the mom to the right, place 02 at 10 L, if no change probably go for a Csection

Question 25

Causes of late deceleration

Answer 25

Oxytocin, pregnancy induced hypertension, postterm pregnancy, amnionitis/infection, small for gestational age from smoking, maternal diabetes, placenta previa, abruptio placenta, Anesthesia producing maternal hypotension in which she would need to get an IV bolus, maternal cardiac disease or anemia

Question 26

Variable late deceleration

Answer 26

Visual abrupt decrease below baseline. Most common decelerations. More than 15 bpm. Lasts at least 15 seconds, but less than two minutes. Occurs any time during contraction. Usually caused by cord compression. U, V, W pattern. They have a sudden drop in a rapid return, sometimes returning over baseline (shoulder).

Change positions, oxygen, give IV fluids, amnioinfusion, decrease oxytocin

First stage of labor is a partial, brief compression of the cord.
Second stage of labor is cord compression during fetal descent

Question 27

Prolonged decelerations

Answer 27

Decrease in the heart rate below baseline at least 15 bpm and lasting more than two minutes, but less than 10

Not associated with hypoxemia

Question 28

Benign changes

Answer 28

Pelvic exam, spiral electrode, rapid fetal descent, sustained maternal Valsalva maneuver which is pushing.

Question 29

Less benign causes we may need to worry about

Answer 29

Progressive severe variable deceleration. Sudden cord prolapse. Hypotension caused by spinal or epidural. Paracervical anesthesia. Tetanic contractions which are long. Maternal hypoxia during a seizure or from preeclampsia
Notify Dr. immediately of prolonged decelerations

Question 30

Amnioinfusion

Answer 30

Put in with the IUPC. Saline or LR. Supplements the amount of amniotic fluid or dilutes meconium stained fluid. Reduces severity of variable Decels caused by cord compression. Reduces the risk for meconium aspiration syndrome.
Oligohydramnios -Low amniotic fluid

Risks include uterine over distention, increased uterine tone, uterine rupture. Not recommended for previous C-section mothers

Question 31

Sinusoidal pattern

Answer 31

A deceleration. Having a visually apparent smooth sine-like wave like undulating pattern in fetal heart rate baseline with a cycle frequency of 3 to 5 minutes that last longer than 20 minutes.

Question 32

Palpation of contractions

Answer 32

Measured at the fundus.

Mild 1+ easily dented
Moderate 2+ slightly indent
Strong 3+ no indent

Question 33

Frequency of fetal heart rate assessment

Answer 33

INTERMITTENT
With no risk factors. Latent phase every one hour. Active phase every 5 to 15 minutes second stage every 5 to 15 minutes. Continuous monitoring if there are risk factors present
ELECTRONIC
No risk factors latent phase every hour, active phase every 30 minutes, second stage every 15 minutes. If there are risk factors latent phase every 30 minutes, active phase every 15 minutes, second stage every five minutes.

Question 34

Transfer of oxygen and CO2 between fetal and maternal bloodstream depends on

Answer 34

Adequate uterine bloodflow. Sufficient placental area. Unconstructed umbilical cord

Question 35

Adequate oxygenation to the fetus depends on

Answer 35

Adequate oxygenation of the mother. Adequate blood flow to the placenta. Adequate uteroplacental circulation. Adequate umbilical circulation. Fetuses ability to regulate the fetal heart rate.

Question 36

Other factors that influence fetal oxygenation

Answer 36

Uteroplacental function. Uterine activity. Umbilical cord issues. Maternal physiological function.

Question 37

Category one

Answer 37

Tracings are normal, looks well oxygenated, with normal acid-base balance.
Baseline normal, variability moderate, late or variable deceleration are absent, early decelerations absent or present. Accelerations absent or present

Question 38

Category two

Answer 38

Indeterminate, not predictive, require evaluation and surveillance.
They can include bradycardia, tachycardia, minimal variability, absent variability, Marked variability, absence of induced accelerations after stimulation, prolonged decelerations, Recurrent decelerations, variable deceleration with a slow return to baseline.

Question 39

Category three

Answer 39

Abnormal. Indicate an abnormal acid-base balance, requires prompt evaluation

Absent variability with recurrently decelerations, recurrent variable deceleration’s, or bradycardia
Or
Sinusoidal pattern

Question 40

Interpretation of fetal heart rate baseline

Answer 40

Rate, variability, acceleration, tachycardia, bradycardia, short and long-term variability

Question 41

Interpretation of periodic and episodic changes

Answer 41

Decelerations either early, variable, late, or prolonged

Question 42

Interpretation of uterine activity

Answer 42

Frequency, duration, intensity, resting tone, relaxation time between contractions

Question 43

Ominous patterns

Answer 43

Absent variability with tachycardia bradycardia under 80, recurrent late decelerations, recurrent variable deceleration’s increasing in depth and duration.

Minimal variability with tachycardia with late deceleration, bradycardia with late decelerations, recurrent late decelerations, recurrent variable deceleration’s increasing in depth and duration

Question 44

Treatment for tachycardia

Answer 44

Give antibiotics or antipyretics. Ice packs with a fever, assess hydration, reduce anxiety, position change or oxygen, decrease or discontinue oxytocin.

Question 45

Reasons for bradycardia

Answer 45

Maternal: supine position, dehydration, hypotension, rupture of uterus, placental abruption, anesthetic, maternal cardiopulmonary compromise

Fetal: response to hypoxia, umbilical cord occlusion, hypoxemia, hypothermia, fetal head compression, bradyarrhythmias

Treatment: confirm monitor is placed right, assess fetal movement, assess response to scalp stimulation, check for prolapsed cord, Change positions, discontinue oxytocin, oxygen, stop pushing,

Question 46

Periodic and episodic changes

Answer 46

Periodic is in relation to contractions and persists over time. Includes accelerations and early, variable, late, and prolonged deceleration.

Episodic are accelerations and decelerations not associated with contractions.

Question 47

Contractions

Answer 47

Frequency is The start of one contraction to the start of the next contraction

Duration is from the beginning to the end of a contraction is measured in seconds

Intensity is the strength of the contraction

Resting tone is the pressure between contractions.

Normal is five or fewer contractions a 10 minute.

Tachysystole is more than five in a 10 minute. It needs to be treated because it can result in decreased uteroplacental blood flow. Characteristics include contractions lasting two minutes or longer, contractions occurring within one minute of each other, increasing resting tone, increasing pressure greater than 80.

Hyperstimulation and tetanic