5. Fetal Assessment Flashcards
Two tools for Hand Held FHR monitoring
- Fetoscope
* Doppler
Two tools for External Electronic Fetal Monitoring
o US transducer –High frequency sound waves
o Tocometer—Measures uterine activity via a pressure sensing device on the abdomen.
Two tools for Internal Electronic Fetal Monitoring
o Scalp elecrode (FSE / ISE)
o Intrauterine pressure catheter (IUPC)
How to assess the “baseline” FHR (2)
- Heartrate assessed between contractions
* Look at a 10 minute strip
Fetal tachycardia (def)
FHR baseline of more than 160 BPM for 10 minutes or longer
Maternal Causes of fetal tachycardia (5)
- Fever, Choriamnitis
- Maternal hyperthyroidism
- Drugs (Tocolytics, etc)
- Dehydration
- Anxiety
Fetal causes of fetal tachycardia (5)
- Early fetal hypoxia
- Asphyxia
- Fetal anemia (Decreased RBCs, Decreased Oxygen)
- Infection
- Prematurity
What is fetal bradycardia a sign of?
Can be a late sign of fetal hypoxia, fetal distress
Causes of fetal bradycardia (5)
- Placental transfer of drugs such as anesthetics
- Prolonged compression of the umbilical cord
- Maternal hypothermia and maternal hypotension
- Maternal supine hypotension syndrome
- These responses in the mother subsequently result in decrease of FHR and ultimately fetal bradycardia.
What causes maternal hypotension syndrome?
• Caused by the weight and pressure of the gravid uterus on the inferior vena cava
What is maternal hypotension syndrome?
• Decreases the return of blood flow which then reduces maternal cardiac output and blood pressure
Fetal Bradycardia (def)
A baseline FHR of less than 110 bpm for a duration of 10 minutes or longer.
Long term v Short Term variability
Long Term variability
• Irregularity of FHR over 10 minutes: Rhythmic waves or cycles from baseline
Short-Term variability
• Fluctuations from beat to beat
Four categories of variability. Which is optimal?
- Absent variability
- Minimal variability
- ** Moderate (avg) variability **
- Marked variability
(Moderate variability is optimal)
Absent variability parameters
VARIABILITY UNDETECTABLE
Minimal variability parameters
Detectable, but less than or = to 5 bpm
Moderate variability parameters
6 to 25 bpm
Marked variability parameters
> 25 bpm
Accelerations (def)
Increase in baseline of 15 bpm for 15 seconds. Indicates fetal well-being.
Decelerations (def)
Decrease in baseline of 15 bpm for 15 seconds.
What do accelerations indicate?
Fetal well-being
What do decelerations indicate?
May be benign or non-reassuring
Periodic changes and what they mean (pneumonic)
VEAL CHOP:
Variable Cord Compressions
Early Head Compressions
Accelerations OK
Late Placental Insufficiency
Characteristics of Early Decelerations • Prognosis • Severity • Pattern, shape • Correlation with contractions
- Prognosis: OK or benign
- Rarely goes more than 30 or 40 below baseline
- Shape is round (like head, the letter U).
- Mirror contractions.
Characteristics of Early Decelerations
• Related to…
• Secondary to…
- Related to vagal nerve stimulation
* Secondary to head compression
Characteristics of Late decelerations
• Shape / pattern
• Related to…
- Slow decrease, slow recovery (shape is rolling hills)
* Related to placental insufficiency
Characteristics of Variable Decelerations
• Related to…
• Correlation with contraction
- Related to Cord compressions
* Late in contraction
Characteristics of Variable Decelerations: Shape / Pattern (3)
- Shape: Looks like a V, U or W.
- Shoulders
- Abrupt decrease with an abrupt return to baseline.
What are shoulders?
Little overcompensations after deceleration. ONLY OCCUR WITH VARIABLE DECELERATIONS.
Early deceleration: Range
Within normal range: 120-160
Late deceleration: Range
Within normal range: 120-130
How often to document FHR assessment during each stage of labor?
• Latent phase
• Active phase
• 2nd stage
- Latent phase: Q1hour
- Active phase: Q15-30 minutes
- 2nd stage: Q5minutes or between contractions
Characteristics of a “reassuring” FHR pattern (4)
- Baseline between 110-116
- No decelerations or changes in baseline
- Accelerations with fetal movement
- Moderate variability
Characteristics of a “non-reassuring” FHR pattern (5)
- Tachycardia
- Bradycardia
- Decreased or absent variability
- Late decelerations
- Severe variable decelerations
What is the first thing you do if there are decelerations
TURN OFF THE PITOCIN
Nursing management of FHR changes (5 - in order)
o If pitocin is infusing, turn off pitocin with decelerations o Position change (left lateral) o Increase IV fluids o O2 (8-10L via face mask) o Notify Provider
Other interventions for FHR changes (4)
o Fetal stimulation
o Amnioinfusion
o Discourage valsalva maneuver
o Change maternal position
Scalp elecrode (FSE / ISE) • What is it • What does it do
- Tiny thing screwed in clockwise
* Takes a fetal ECG and turns it into a fetal HR
Intrauterine pressure catheter (IUPC)
• what does it do?
Measures the pressure inside the uterus
