Fetal Monitoring and Fetal Assessment

A few new techniques and protocols!

IA= Intermittent Auscultation

• At the start of the 20th Century, IA of the FHR during labor was the predominant method of assessment.

• IA is the practice of using a device that allows one to listen to the fetal heart sounds over time.

• Examples would be placing the ear over the pregnant abdomen, using a fetoscope, or using a Doppler.

EFM= Electronic Fetal Monitoring

• Research in Randomized Clinical Trials on Low-risk pregnancies has demonstrated that (Anderson, 1994) – “The use of EFM as compared with IA has not been

shown to reduce neonatal morbidity or mortality rates but has been associated with increased rates of cesarean section and maternal infection” (p. 165).

EFM= Electronic Fetal Monitoring

• This research is a cause for concern as we look at research-based practice and the fact that we are doing “stuff” that has not been necessarily supported by research!

• Something to think about and ponder! • The future practice of EFM may change if

agencies choose to practice based on clinical research findings.

Clinical Decision-making Based on Auscultation Findings

Auscultate FHR

Interpretation

Reassuring FHR Pattern?•Baseline rate 110-160•Regular rhythm•Absence of decrease from baseline

Continue IndividualizedAssessment and Care

• Assess with IA & palpation per pt/care provider preferences, guidelines, & availability (1:1 nurse to fetus ratio)• Promote maternal comfort & continued fetal oxygenation(position change; anxiety reduction measures• Notify midwife or MD when a problem exists or is resolved

Yes

No

Non-Reassuring FHR Pattern•Baseline <110 pbm•Baseline >160 bpm (unexplained persistent tachycardia for > 3 contractions or > 10-15 minutes•Irregular rhythmFHR during & 30 seconds after contractions•Gradual or abrupt change in FHR

Intervention/Management frequency of IA to clarify FHR charracteristicsAssess potential cause of FHR characteristicsAttempt to remove problem(s)/causeIntervene to promote 5 physiologic goals:

Improve uterine blood flowImprove umbilical blood flowImprove oxygenation uterine activity (e.g. position change, hydration)

Problem Solved??

YES—Return to Continued Individualized Assessment & Care

FHR Pattern Persists?Continue interventionsApply EFM to clarify pattern interpretation, assess variability, to further assess fetal statusNotify midwife or MDConsider additional assessments (e.g. fetal scalp stimulation; fetal acoustic stimulation)

No

Goals of Physiologic Interventions

Improve Uterine Blood FlowMaternal position changeHydrationAnxiety reductionMedication

Improve OxygenationMaternal position changeMaternal oxygenMaternal breathing techniques

Improve Umbilical CirculationMaternal position change Vaginal manipulationAmnioinfusion

Reduce Uterine ActivityMaternal position change HydrationModified pushingMedication (e.g. discontinue or rate of labor-stimulating drug infusion

Definitions of Fetal Heart Rate Patterns National Institute of Child Health

and Human Development (NICHD) PATTERN DEFINITION

Baseline •The mean FHR rounded to increments of 5 bpm during a 10 min. segment, excluding:

- Periodic or episodic changes

- Segments of baseline that differ by more than 25 bpm

•The baseline must be for a minimum of 2 min. in any 10 min. segment

PATTERN DEFINITION

Baseline Variability

•Fluctuations in the FHR of two cycles per min or greater

•Variability is visually quantitated as the amplitude of peak-to-trough in bpm- -Absent—amplitude range undetectable- -Minimal—amplitude range detectable but 5 bpm or fewer- -Moderate (normal)—amplitude range 6-25 bpm-

-Marked—amplitude range greater than 25 bpm

PATTERN DEFINITION

Acceleration •A visually apparent increase (onset to peak less than 30 sec.) in the FHR from the most recently calculated baseline

•The duration of an acceleration is defined as the time from the initial change in FHR from baseline to the return of the FHR to baseline

•At 32 weeks of gestation and beyond, an acceleration has an acme of 15 bpm or more above baseline, with a duration of 15 sec. or more but less than 2 min.

•Before 32 weeks gestation an acceleration has an acme of 10 bpm or more above baseline, with a duration of 10 sec. or more but less than 2 min.

•If an acceleration lasts 10 min. or longer it is a baseline change

PATTERN DEFINITIONBradycardia

Early deceleration

•Baseline FHR less than 110 bpm

•In association with a uterine contraction, a visually apparent, gradual (onset to nadir 30 sec. or more) decrease in FHR with return to baseline*Nadir of the deceleration occurs at the same time as the peak of the contraction

PATTERN DEFINITIONLate deceleration

Tachycardia

•In association with a uterine contraction, a visually apparent, gradual (onset to nadir 30 sec. or more) decrease in FHR with return to baseline

•Onset, nadir, and recovery of the deceleration occur after the beginning, peak, and end of the contraction, respectively

•Baseline > 160 bpm

PATTERN DEFINITIONVariable Deceleration

Prolonged Deceleration

•An abrupt (onset to nadir less than 30 sec), visually apparent decrease in the FHR below the baseline

•The decrease in FHR is 15 bpm or more, with a duration of 15 seconds or more, but < 2 minutes

•Visually apparent decrease in FHR below the baseline

•Deceleration is 15 bpm or more, lasting 2 minutes or more but less than 10 minutes from onset to return to baseline.

That’s it for now!!

• Have fun learning more about the Fetal Heart Monitor on the clinical unit!

• Technology is really going places in fetal surveillance, so who knows what will be next!!