1. Fetal Health Surveillance (FHS): Part 1 - Introduction
Maternal Newborn Orientation Learning Module
Reproductive Care Program of Nova Scotia
Revised July, 2013

2. Objectives Review physiology influencing the fetal heart rate
Describe tools for fetal surveillance
Doppler
The electronic fetal monitor (EFM)
Review Intermittent Auscultation (IA) of the FHR

3. References:

4. Physiology related to the FHR
Intrinsic and extrinsic factors
Homeostatic mechanisms

5. Internal mechanisms of FHR control
Intrinsic Factors
Internal mechanisms of FHR control
Central Nervous System
Medulla oblongata – controls HR, BP
Mid-brain to cortex – controls FHR and changes that occur in response to fetal states and activity
Autonomic Nervous System
Sympathetic -  FHR, strength of cardiac contractions
Parasympathetic -  FHR via vagus nerve

6. Intrinsic factors Hormones - catecholamines Epinephrine
 HR, BP, stroke volume and cardiac output
Norepinephrine
 blood flow to vital organs during hypoxemia
Angiotensin, aldosterone
potent vasoconstrictors acting in response to hemorrhage or hypoxemia

7. Intrinsic factors Baroreceptors Chemoreceptors
‘pressure receptors’ located in aortic arch and carotid
respond to changes in BP to  or  the FHR
Chemoreceptors
located in aortic arch, carotid, and medulla oblongata
respond to changes in pO2 and pCO2 to  or  the FHR

8. Intrinsic factors Fetal behavioral states and development
Quiet/active sleep, awake
Advancing gestation
Used with permission, 2013 NCAST
University of Washington

9. Extrinsic factors
Factors in the fetal environment that affect oxygen availability, fetal well-being, and the FHR
Maternal health
Placenta
Umbilical cord

10. Extrinsic factors Maternal influences:
pO2 – respiratory status, smoking
O2 carrying capacity – Hgb, blood volume
Uterine blood flow – circulation, venous return
Uterine contractions – normal, tachysystole, hypertonus

11. Extrinsic factors - placenta
Maternal arterioles

12. Extrinsic factors
Normal placenta
Calcified placenta

13. Extrinsic factors

14. Umbilical Cord Abnormalities
Nuchal cord
True knot

15. Extrinsic factors
Umbilical cord influences

16. Homeostatic Mechanisms
Regulating mechanisms that allow the fetus to adapt to the stresses of labour and birth
Reflex responses
Normal responses
Compensatory responses
Protect fetal integrity
Dependent on fetal reserve
Decompensation

17. Methods and tools for FHS
William’s Obstetrics

18. 1 2
Leopold’s Maneuver -
an essential skill 4 3
William’s Obstetrics

19. Fetal Health Surveillance - Principles
SOGC advises: (2007) ‘The normal, healthy fetus is well-equipped to withstand the repeated, transient hypoxia associated with labour contractions.’ ‘Intermittent auscultation (IA) is the preferred method of fetal surveillance for healthy women without risk factors for adverse outcomes’.

20. Decisions around methods of FHS
Always consider a woman’s choice
Use of EFM supported for pregnancies with complications
Hypertension  Postmaturity >42 weeks
 IUGR  Prematurity
Multiple pregnancies
Continuous EFM for augmentation / ‘mostly continuous’ for induction

21. Auscultation
Auscultate the FHR q 15 minutes in active labour, q 5 minutes during second stage once active pushing has begun

22. Auscultation procedure
60-second count ‘results in greatest accuracy’
Baseline rate is assessed between contractions.
Check maternal pulse to confirm FHR
Record rate, rhythm (regular or irregular), and accelerations (abrupt increases) and/or decelerations (gradual or abrupt)

23. Ausculation classification
Normal FHR:
FHR 110 to 160
Regular rhythm
Accelerations
Abnormal FHR:
Outside normal range
Decelerations

24. Documentation – NS Partogram (RCP)

25. If the FHR is abnormal on auscultation….
‘Auscultate the FHR after the next contraction to confirm the characteristics’ (SOGC)
Assess potential causes – attempt to eliminate or reduce the effect
Recheck maternal pulse, V/S
Initiate EFM

26. Part 2… Analysis and interpretation of EFM tracings
Interventions recommended in the event of atypical or abnormal tracings

27. Thank you!
We welcome your feedback. Please take a few moments to complete a short evaluation:
If you have any questions, please contact the RCP office at or