Fetal Heart Rate Assessment (Ch.9) Flashcards
What does assessing a fetal heart rate (FHR) tell the nurse?
-Fetal oxygenation
What does acceleration mean?
Increase in FHR above baseline (>15 bpm over baseline for 15 seconds for 2 minutes)
What does deceleration mean?
Decrease from baseline
Can be periodic or intermittent
What is a late deceleration?
Gradual decrease of FHR taking more than 30 seconds
- Lowest point is at the peak of contraction
- Always periodic
What is prolonged deceleration?
Decrease FHR that is >15 bpm lasting > 2minutes but < 10 minutes
-Can be periodic or intermittent
What is a normal heart rate?
110-160
FHR tachycardia
> 160 lasting 10 minutes or longer
FHR bradycardia
<110 bpm lasting 10 minutes or longer
What is contraindicated with internal fetal monitoring on quiz
- Active genital herpes
- Positive group B streptococcus
- Placenta previa
- Undiagnosed vaginal bleeding
- Chorioamnionitis
How does internal electronic uterine monitor work?
Catheter is placed in the uterine cavity to directly measure uterine contractions
-Membranes must be ruptured
What is a tocodynamometer?
External electronic devices for monitoring and recording uterine contractions during labor
-Cannot measure intensity
What are some reasons you would use internal monitoring versus external?
- Maternal Obesity
- Lack of progress in labor
- Treat a worsening Category 2 tracing via amnioinfusion
How do you know if the strength of the uterine contraction is good?
At least 200 MVUs every 10 minutes for 2 hours
What does the top grid of monitor paper tell you?
FHR
What does the lower grid of monitor paper tell you?
Uterine contraction
What is an issue with external monitoring?
It can pick up the maternal HR instead of the fetus and will show a low HR
How does the parasympathetic nervous system effect the baby?
Slows FHR and helps maintain variability
What does the FHR look like if they have a little hypoxia and are able to deal with it?
Variable decelerations
What hormonal regulations occur when the fetus is hypoxic?
Release of epinephrine and nor-epinephrine that increase FHR and BP
What are the three types of fetal responses that?
No hypoxia = Accelerations
Compensating = Variable deceleration
Decompensation = Late deceleration
What is a category 3 predictive of?
Abnormal fetal acid base balance and require promote evaluation
Which of the following FHR patterns indicated a normal FHR? A. Category 1 B. Category 2 C. Category 3 D. None of the above
A. Category 1
Intrauterine Resuscitation Interventions if goal is to Promote Fetal Oxygenation
~Administer oxygen at 10 L/min via nonrebreather face mask (DC ASAP based on fetal response)
~Lateral positioning (L or R side)
~IV Fluid bolus of ≤ 500 mL LR solution
~DC oxytocin, remove dinoprostone insert, or withhold next dose of misoprostol
~Alter pushing to every other contraction or temporarily stop pushing (during second stage of labor)
Intrauterine Resuscitation Interventions if goal is to Reduce Uterine Activity
~DC oxytocin, remove dinoprostone insert, or withhold next dose of misoprostol
~IV Fluid bolus of ≤ 500 mL LR solution
~Lateral positioning (L or R side)
~If no response, consider administration of 0.25 mg SQ terbutaline
Intrauterine Resuscitation Interventions if goal is to Alleviate Umbilical Cord Compression
~Repositioning
~Amnioinfusion (during first-stage labor)
~Alter pushing to every other contraction or temporarily stop pushing (during second stage of labor)
~Umbilical cord prolapse, elevate the presenting fetal part while preparations are made for an expected birth
Intrauterine Resuscitation Interventions if goal is to Correct Maternal Hypotension
~Lateral positioning (L or R side)
~IV Fluid bolus of ≤ 500 mL LR solution
~If no response, consider ephedrine 5-10 mg IV push
What can Fetal tachycardia be a sign of?
Early fetal hypoxemia especially with decreased variability and deceleration
What are some maternal causes of fetal tachycardia?
~Fever ~Infection (check allergies) ~Dehydration ~Epinephrine, Terbutaline ~Cocaine
What heart rate can cause fetal demise if it persists?
200-220
Nursing actions to fix fetal tachycardia
Treat underlying cause of tachycardia such as antibiotics for infection, antipyretics for fever, and fluids for dehydration
~Assess maternal VS (temp)
~Assess hydration by checking skin turgor, mucous membranes, urine specific gravity, I/O
~Decrease or DC Oxytocin
When is fetal bradycardia considered an emgergency?
Sudden profound bradycardia (less than 80 bpm)
Is fetal bradycardia of >80 with variability (fluctuations) considered good, okay, bad?
Okay needs to be monitored but not horrible
What type of fetal bradycardia is associated with current or impending fetal hypoxia?
Bradycardia with loss of variability or late deceleration
What are some maternal causes to fetal bradycardia?
~Supine position
~Dehydration
~Hypotension
~Placental abruption
What are some fetal causes to fetal bradycardia?
~Fetal response to hypoxia
~Baby is laying on umbilical cord
~Fetal head is compressed
If using external monitoring and the FHR indicates bradycardia, what do you need to check?
Check the mother’s radial pulse because the EFM may be picking up the mother’s heart rate
Nursing actions to fix fetal bradycardia
~Sterile vaginal exam to see fetal response to touching the head
~Vaginal exam for prolapsed cord
~Intrauterine Resuscitation Interventions
What is the most important predictor of adequate fetal oxygenation and fetal reserve during labor
Baseline variability
What is the gold standard for variability (fluctuations)?
Moderate (6-25 bpm) shows well-oxygenated fetus with normal acid-base balance
What are the different types of variability (fluctuations) ?
Absent: looks like flatline
Minimal: undetectable below 5 bpm
Moderate: Amplitude from 6-25 bpm
Marked: Greater than 25 bpm
Maternal causes of minimal or absent variability (fluctuations)
~Supine hypotension
~Cord Compression
~Uterine tachysystole
~Drugs (illicit drugs, alcohol)
How do you confirm minimal or absent variability (fluctuations)?
Artificial rupture of membranes and more invasive internal monitoring with fetal spiral electrode
Nursing actions for minimal or absent variability (fluctuations)
Intrauterine Resuscitation Interventions
What are the four types of deceleration?
- Early
- Variable
- Late
- Prolonged
What are episodic changes?
Accelerations and deceleration patterns not associated with contraction
Most common is accelerations
What are FHR accelerations predictive of?
Adequate oxygenation and require no interventions
What does early decelerations indicate?
Occur with contractions and is a normal response and require no intervention
-Fetal head compression
What is the most common deceleration seen in labor?
Variable deceleration
-caused by umbilical cord compression
Characteristics of normal variable decelerations
- Duration of less than 60 seconds
- Rapid return to baseline
- Normal baseline and variability
Define an “overshoot”
Accelerations at the beginning and end of decelerations
Treatment for abnormal variable decelerations
Intrauterine Resuscitation Interventions
What are late decelerations a sign of for the fetus?
Fetal intolerance to labor
-uteroplacental insufficiency
What is usually the problem with late decelerations?
Placenta
What three things do you look at for uterine activity?
- Frequency (beginning of one to start of next)
- Intensity (strength)
- Duration (beginning to end of same contraction)
What is the normal amount of contractions in a 10 minutes averaged over 30 minute period?
5 or fewer
What is a big concern if the uterus is in tachysystole?
the uterus could rupture
Characteristics of tachysystole of the uterus
~More than 5 UC in 10 minutes
How do you treat tachysystole of the uterus?
DC medication that caused it and Intrauterine Resuscitation Interventions
What does magnesium sulfate do for preterm labor?
Decreases FHR variability and acceleration amplitude in preterm infants
What is the normal type of deceleration?
Early decelerations (FHR is responding to UC)
