1. Fetal Monitoring Basics Expanded
NUR 231
M. Johnston, RN-BC, M.Ed.
Cindy Irwin , RNC, MN

2. Types of Monitoring
Auscultation- listen to fetal heart rate (FHR) Electronic Fetal Monitoring – use of instruments to record FHR and uterine contractions(U/Cs)

3. Auscultation
Doppler - ultrasound converts sounds waves to signals of fetal heart
Fetoscope - Like stethoscope, open end pressed on abdomen, used less frequently

4. Electronic Fetal Monitoring
Measures response of FHR to uterine contractions (U/Cs)
Intermittent or Continuous
External
Ultrasound transducer
Tocotransducer
Internal
Fetal Scalp Electrode
Intrauterine Pressure Catheter

5. Fetal Monitoring Setup

6. Fetal Heart Rate Characteristics
Evaluate to determine fetal status
NICHD terminology
Baseline Rate
Baseline Variability
Accelerations (present or absent)
Decelerations (present or absent)
Changes or trends over time

7. Baseline (BL) Normal range 110-160 bpm
Measure between U/Cs for at least 2 min. period during 10 minute segment
Tachycardia - >160 bpm for >10 minutes
Bradycardia - <110 bpm for >10 minutes

8. Baseline

9. Classifications of FHR Variability
Fluctuations in FHR, irregular in frequency and amplitude
Absent bpm
Minimal >2 <6 bpm
Moderate bpm
Marked >25 bpm

10. Absent Variabilty

11. Minimal Variability

12. Moderate Variability

13. Marked Variability

14. Periodic/Episodic Changes Periodic with uterine contractions Episodic without uterine contractions

15. Accelerations Abrupt increase in FHR above BL Present or Absent
< 32 wks gestation
Peak ≥ 10 bpm above BL for at least 10 sec.
>32 wks gestation
Peak ≥ 15 bpm above BL for at least 15 sec.
Accel ≥ 10 min. is defined as BL change

16. Accelerations Abrupt increase in FHR above BL
Peak ≥ 15 bpm above BL for at least 15 sec.
Increase in FHR with fetal activity, just like adult HR increases with exercise
At times, fetus moves in response to U/Cs
A sign of fetal well-being

17. Recognition Criteria for Fetal Heart Rate Accelerations
Transient increase in the Fetal Heart Rate
> 32 weeks acceleration stays 15 beats above the baseline for at least 15 seconds
< 32 weeks acceleration stays 10 beats above the baseline for at least 10 seconds

18. Types of Decelerations
Early – Gradual decrease and return to BL, mirrors the U/C
Variable – Abrupt (<30 sec) decrease (≥15 sec down, lasting ≥ 15 sec and <2 min from onset to return to BL)
Late – Gradual decrease (≥30 sec) and gradual return to BL; delayed timing nadir occurs after peak of U/C
Prolonged – Decrease in FHR below BL ≥15 sec, lasting ≥ 2 min. but <10 min.

19. Early Deceleration
Gradual decrease and return to BL
Mirrors the U/C

20. Early Deceleration

21. Early Decelerations Usually benign
May be associated with descent of fetus
Monitor to assure fetal well-being, no evidence of worsening condition

22. Variable Deceleration
Abrupt (<30 sec) decrease (≥ 15 sec down, lasting ≥ 15 sec and < 2 min. from onset to return to BL)

23. Variable Decelerations

24. Variable Deceleration- Cause and Treatment
Umbilical cord compression resulting in baroreceptor stimulation
Treatment-
Assess baseline variability, rate
Reposition mother
Notify provider
Check for cord prolapse
Apply internal monitors
 or turn off oxytocin
Administer O2 by mask
Prepare for possible amnioinfusion
Document interventions/FHR response

25. Late Deceleration Gradual decrease (≥ 30 sec) and gradual return to BL
Delayed timing, nadir occurs after peak of U/C

26. Late deceleration

27. Late decelerations - Cause and Treatment
Cause- Placental insufficiency
Treatment
Assess baseline variability, rate, accelerations
Reposition mother on side
 IV fluids
 or turn off oxytocin
Notify provider
Administer O2 by mask
Apply internal monitors
Evaluate scalp stimulation
Document interventions/FHR response
Exit plan

28. Prolonged Deceleration
Decrease in FHR below BL ≥ 15 sec, lasting ≥ 2 min. but < 10 min.

29. Causes of Prolonged Decelerations
Uterine hyperstimulation or hypertonus
Abruptio placenta
Acute maternal hypotension
Uterine rupture
Maternal hypoxia
Umbilical cord accidents
Terminal fetal conditions
Vasa previa
Rapid fetal descent
Vagal stimulation or maternal Valsalva

30. Treatment for Prolonged Decelerations
Notify provider
Assess baseline variability, rate, accelerations Reposition mother on side
 IV fluids
 or turn off oxytocin
Administer O2 by mask
Apply internal monitors
Do not attempt scalp stimulation
Document interventions/FHR response
Exit plan

31. Sinusoidal FHR

32. Fetal Heart Rate Patterns
Indeterminate
FHR tracings that do not
meet the criteria for
Normal or Abnormal
Abnormal
Absent baseline variability
and any of the following:
Recurrent late decels
Recurrent variable decels
Bradycardia or
Sinusodial pattern
Normal
ALL required:
Moderate variability
Baseline rate
No late or variable decels
Early decels present or
absent
Accels: present or absent
Category I
Strongly associated with normal acid base status
Category II
Not predictive of abnormal fetal acid base status but inadequate evidence to classify as normal or abnormal
Category III
Predictive of abnormal fetal acid base status

33. Fetal Heart Rate Interpretation System
Category l
Associated with normal acid base balance
Category ll
Inadeq. evidence to classify as normal or abnormal
Category lll
Predictive of abnormal acid base status
Normal
Category l ALL of the following: normal BL, mod variability, accels present or absent, no late or variable decels, may have earlies
Category ll ANY of the following: tachy, brady without abesnt variab. Min variabl. etc Requires continued surveillance and reevaluation
Category lll EITHER sinusoidal pattern or absent variability w/ recurrent lates, recurrent variable decels or bradycardia
Indeterminate
Abnormal

34. FHR Interpretation
Information about fetal oxygenation/placental function
Somewhat subjective
Abnormal patterns may need further testing

35. Monitoring Uterine Contractions
Assess U/C pattern while assessing FHTs
External
Palpation
EFM Toco measures frequency, duration
Noninvasive
Internal
Intrauterine pressure catheter (IUPC)
Measures exact intrauterine pressure
Invasive

36. Why Monitor?
FHR changes in response to oxygenation, gestation, and certain stimuli
EFM provides more objective data than auscultation
Infers information about current and ongoing fetal oxygenation
EFM slightly more objective than Auscultation
Shows fetal response to U/Cs
Auscultation good for low risk; concerns? EFM helps to recognize patterns so need con’t record for interpretation

37. Interventions Abnormal FHR pattern: Notify provider
Change maternal position
Give oxygen via mask
Increase IV fluids
Consider medication to relax uterus

38. Other Fetal Surveillance
Non-Stress Test (NST) - EFM
Contraction Stress Test (CST) - EFM
Biophysical Profile (BPP) - U/S
Doppler Flow Studies/Growth - U/S
Fetal Movement Count-maternal sensation/palpation

39. Intermittent Auscultation
What’s the evidence?
ACOG, AWHONN support the use of auscultation as an appropriate way to evaluate fetal heart rate for the uncomplicated patient
Neonatal outcomes comparable to those with use of EFM based on randomized clinical trials

40. Technique for IA Assess contractions by palpation
Determine fetal position
Determine maternal pulse rate
Place Doppler over fetal back or thorax
Determine baseline FHR by listening between contractions for seconds: differentiate from maternal HR
Count FHR immediately after contraction for seconds
Chart under Intermittent Auscultation- Baseline, Rhythm, Increases, Decreases

42. How often? On admission, obtain 20 minute FM tracing
If Category I tracing, no risk factors present, and provider order for IA:
Document FHR and uterine activity:
Latent phase: As ordered
Active labor: Every minutes
Second stage: Every 5-15 minutes

43. Comparison Model for Palpation of Uterine Activity
PALPATION OF UTERUS FEELS LIKE CONTRACTION INTENSITY
• Easily indented • Tip of nose • Mild
• Can slightly indent • Chin • Moderate
• Cannot indent • Forehead • Strong

44. Limitations
Difficult to hear FHR with if pt obese, has an increased AFI, or with maternal or fetal movement
No tracing to review at a later time
Certain EFM characteristics cannot be measured (sinusoidal pattern)
Requires practice

45. Benefits
Lower C/S and operative delivery rates compared to EFM for patients without risk factors
Allows maternal freedom of movement/ambulation
Increased hands-on contact with patient
Increased patient satisfaction