New Guidelines for Fetal Heart Rate Monitoring: How to Adopt Them

Mary E. D’Alton, MDWillard C. Rappleye Professor

Chair, Department of Obstetrics and Gynecology

Columbia University College of Physicians and Surgeons

New York, New York

All the possibilities of modern medicine

Intrapartum FHR monitoring is the single most common obstetric procedure in the US, impacting the lives of almost 4 million mothers and babies every year

Background

Identified “poor communication of abnormal FHR patterns” as a leading risk factor for preventable perinatal injury

Recommended that hospitals educate nurses, residents, nurse midwives, and physicians to use standardized terminology to communicate abnormal fetal heart rate tracings.

The commission further recommended that healthcare organizations develop clear guidelines for interpretation of FHR patterns…

Joint CommissionSentinel Event Alert: Issue 30 –July 21, 2004

The purpose of the National Institutes of Health research planning workshops is to assess the research status of clinically important areas. This article reports on a workshop whose meetings were held between May 1995 and November 1996 in Bethesda, Maryland, and Chicago, Illinois. Its specific purpose was to develop standardized and unambiguous definitions for fetal heart rate tracings. The recommendations for interpreting fetal heart rate patterns are being published here and simulatneously by the Journal of Obstetric, Gynecologic, and Neonatal Nursing. (Am J Obstet Gynecol 1997; 177:1385-90).

Efficacy: Cochrane Review

12 clinical trials (n=37,000), 2 of high quality No “non monitoring” studies Most are dated

Continuous EFM compared to intermittent auscultation

Alfirevic et al. Cochrane 2006 (3) #CD006066

N (trials) RR 95% CIPerinatal Death 33,513 (11) 0.85 0.59-1.23Neonatal Seizures 32,386 (9) 0.50 0.31-0.80Cerebral Palsy 13,252 (2) 1.74 0.97-3.11Cesarean Delivery 18,761 (10) 1.66 1.30-2.13Operative VD 18,151 (9) 1.16 1.01-1.32

No reduction in cerebral palsyDramatic increase in cesarean delivery

0

5

10

15

20

25

30

35

1970 1975 1980 1985 1990 1995 2000 2005

Cesarean

US Preventive Task Force Grade: D• No evidence of benefit• Evidence of harm

66% 85%

Cesarean delivery rate

%

Intrapartum Monitoring

% of US women with cEFM in labor

Continuous Intrapartum Fetal Heart Rate Monitoring

Why EFM does not seem to be efficacious:1. Use of an outcome measure that is not related to

variant FHR patterns2. Lack of standardized interpretation3. Disagreement regarding algorithms for intervention4. Inability to demonstrate reliability, validity, and ability

of FHR monitoring to allow timely intervention

Intrapartum FHR monitoring is not a failed technology

It is a success on at least three fronts: Its introduction coincided with the virtual

elimination of intrapartum fetal death It is at least as effective as intensive

intermittent auscultation, the only alternative that has been studied in prospective trials

While not a reliable DIAGNOSTIC test, it is an exceptional SCREENING test

The other side…

Sponsored by: NICHD

ACOG

SMFM Additional groups represented:

ACNM AWHONN

AAP RCOG

SOGC National Cardiovascular

Center - Japan

‘The RCOG System – 2001’

‘The use and interpretation of cardiotocography in intrapartum fetal surveillance’

RCOG Evidence-based Clinical Guideline No 8

Adopted by National Institute of Clinical Excellence (NICE)

Published for May 2001

For this Workshop focus on terminology used in EFM

Courtesy of Dr. David James

Four arguments for development of EFM Guidelines:

1. Intrapartum hypoxia

1% of all labors

10% perinatal deaths(Confidential Enquiry into Stillbirths and Deaths in Infancy [CESDI])

Intrapartum hypoxic death rate: 0.8 in1000 births

10% CP cases

Intrapartum hypoxic CP rate: 0.1 in 1000 births

Courtesy of Dr. David James

2. EFM use 239/248 (96.4%) maternity units in UK

use EFM 26% did not have an EFM Guideline

(30% in units > 3000 deliveries) Fetal blood sampling used in 88%

Courtesy of Dr. David James

Four arguments for development of EFM Guidelines:

3. Suboptimal EFM use CESDI reported that 70% of intrapartum

deaths have suboptimal care Majority of examples relate to EFM

Failure to recognize Failure to act Communication failure

Courtesy of Dr. David James

Four arguments for development of EFM Guidelines:

4. Medicolegal issues

> $800 million estimate of NHS medicolegal costs currently

> 60% are obstetric cases

Majority of obstetric cases relate to fetal monitoring in labor

Courtesy of Dr. David James

Four arguments for development of EFM Guidelines:

Courtesy of Dr. David James

Courtesy of Dr. David James

Courtesy of Dr. David James

RCOG Management Recommendations

In cases where the CTG falls into the suspicious category, conservative measures should be used

In cases where the CTG falls into the pathological category, conservative measures should be used Fetal blood sampling should be used where

appropriate and feasible In situations where fetal blood sampling is not

possible or appropriate, delivery should be expedited

Risk of acidemia, evolution of FHR patterns to more serious risk, and recommended action

Variable Risk of acidemiaRisk of evolution

Action

Green 0 Very low None

Blue 0 LowConservative techniques &

begin preparation

Yellow 0 ModerateConservative techniques &

increased surveillance

OrangeBorderline/acceptably low

HighConservative techniques & prepare for urgent delivery

Red Unacceptably highNot a consideration

Deliver

Am J Obstet Gynecol 2007; 26.e3

Risk categories for fetal acidemia related to FHR variability, baseline rate and presence of recurrent decelerations.MODERATE (NORMAL) VARIABILITY

No Early Mild VD Mod VD Sev VD Mild LD Mod LD Sev LD Mild PD Mod PD Sev PD

Tachy B B B Y O Y Y O Y Y O

Normal G G G B Y B Y Y Y Y O

Mild Brd Y Y Y Y O Y Y O Y Y O

Mod Brd Y Y O O O O

Sev Brd O O O O O

MINIMAL VARIABILITY

No Early Mild VD Mod VD Sev VD Mild LD Mod LD Sev LD Mild PD Mod PD Sev PD

Tachy B Y Y O O O O R O O O

Normal B B Y O O O O R O O R

Mild Brd O O R R R R R R R R R

Mod Brd O O R R R R

Sev Brd R R R R R

ABSENT VARIABILITY

No Early Mild VD Mod VD Sev VD Mild LD Mod LD Sev LD Mild PD Mod PD Sev PD

Tachy R R R R R R R R R R R

Normal O R R R R R R R R R R

Mild Brd R R R R R R R R R R R

Mod Brd R R R R R R

Sev Brd R R R R R

Sinusoidal R

Marked Variability Y

VD, Variable decelerations; LD, Late decelerations; PD, Prolonged decelerations; Brd, Bradycardia; Tachy, Tachycardia

G, Green; B, Blue; Y, Yellow; O, Orange

The “Miller Method” of EFM Interpretation

www.SOGC.org

Normal tracingPreviously “Reassuring”

Atypical TracingPreviously “Non-reassuring”

Abnormal TracingPreviously “Non-reassuring”

BASELINE 110-160 bpm Bradycardia 100-110 bpm Tachycardia > 160 for 30-80 min Rising baseline

Bradycardia < 100 bpm Tachycardia > 160 for < 80 min. Erratic baseline

VARIABILITY 6-25 bpm ≤ 5 bpm for < 40 min. ≤ 5 bpm for 40-80 min.

≤ 5 bpm for > 80 min. ≥ 25 bpm for > 10 min. Sinusoidal

DECELERATIONS

None Occasional uncomplicated

variables Occasional early

decelerations

Repetitive (≥ 3) uncomplicated variable decelerations

Occasional late decelerations Single prolonged deceleration

lasting > 2 min. but < 3 min.

Repetitive (≥ 3) complicated variables

ACCELERATIONS

Spontaneous accelerations present

Accelerations present with fetal scalp stimulation

Absence of acceleration with fetal scalp stimulation Usually absent

ACTION

EFM may be interrupted for periods up to 30 min if maternal-fetal condition stable and/or oxytocin infusion rate stable

Further vigilant assessment required, especially when combined features present.

ACTION REQUIRED: Review overall clinical situation, obtain scalp pH if appropriate; prepare for delivery

SOGC EFM Classification System:

SOGC Normal Tracing

Baseline: 110-160 bpm Variability: 6-25 bpm or < 5 bpm or < 40 min Decelerations:

Frequency: None or occasional Type: Uncomplicated variables or early

Accelerations: Spontaneous accelerations present

OR accelerations with scalp stimulation > 15 bpm for > 15 sec at > 32 weeks > 10 bpm for > 10 sec at < 32 weeks

Action: EFM may be interrupted for periods < 30 min IF maternal condition and oxytocin infusion rate is stable

SOGC Atypical Tracing

Baseline: 100-110 bpm or > 160 bpm for >30

and < 80 min OR rising baseline Variability: < 5 bpm for 40-80 min Decelerations:

Repetitive (>3) uncomplicated variables Occasional late decelerations Single prolonged deceleration > 2 min but < 3 min

Accelerations absent with scalp stimulation Action: Further vigilant assessment required,

especially if multiple features present

SOGC Abnormal Tracing

Baseline: Bradycardia (< 100 bpm), tachycardia (> 160

for < 80 min), OR erratic baseline Variability: < 5 bpm for > 80 min, > 25 bpm for > 10

min, OR sinusoidal

Decelerations: Repetitive (>3) COMPLICATED variables Deceleration to < 70 bpm for > 60 sec or single

prolonged deceleration > 3 min but < 10 min Loss of variability in trough Overshoots Slow return to baseline Late decelerations > 50% of contractions

Accelerations usually absent Action: Review clinical situtation, obtain scalp pH if

appropriate, and prepare for delivery

Summary of EFM Interpretation Systems

1997 NICHD: 2 tier RCOG: 3 tier

Extensive vetting and peer review National implementation, 50% drop in intrapartum death rate

SOGC: 3 tier Extensive vetting and peer review

Parer: 5 tier Applied knowledge, interdisciplinary Variability driven

Miller: 3 tier Least stringent Common sense approach Definition, interpretation, management

NICHD Workshop: Objectives

Update definitions System needs to be SIMPLE and evidence

based Need consistency of FHR description across

the country Develop research agenda

NICHD: Assumptions

The definitions were developed for visual interpretation of FHR patterns

FHR pattern features: baseline, episodic and periodic

No distinction is made between short term and long term variability

FHR tracings should be evaluated in context of clinical conditions (GA, medications, maternal medical conditions, fetal conditions)

An EFM requires QUALITATIVE and QUANTITATIVE description of all of the following components: Uterine contractions Baseline FH rate Baseline FHR variability Presence of accelerations Periodic or episodic decelerations Changes or trends of FHR patterns over time

NICHD:Description of FHT Components

Number of uterine contractions per 10 minute window

Averaged over 30 min Normal: ≤ 5 contractions in 10 min Tachysystole: > 5 contractions in 10 min

Presence or absence of decelerations Spontaneous and stimulated labor The terms “hyperstimulation” and

“hypercontractility” are to be abandoned

NICHD:Description of Contractions

NICHD: Describing FHR Baseline

Rounded to 5 bpm Assembled from segments of baseline totaling

at least 2 min with in a 10 min window Excludes periods of accelerations,

decelerations and hypervariability Bradycardia is < 110 bpm Tachycardia is > 160 bpm

FHR Baseline

NICHD: Describing FHR Variability

FHR Variability

Excludes accelerations, decelerations Quantitated as peak-to-trough Absent variability: amplitude undetectable Minimal variability: amplitude detectable but

≤ 5 bpm Moderate variability: amplitude 6-25 bpm Marked variability: amplitude > 25 bpm

Absent Variability Minimal Variability

Marked VariabilityModerate Variability

NICHD: Describing Accelerations

Abrupt increase in FHR Onset to peak < 30 seconds

Peak: ≥ 15 bpm lasting 15 seconds from onset to return to baseline

Prolonged acceleration: ≥ 2 min but < 10 min Acceleration > 10 min = baseline change

NICHD: Describing Decelerations

Decrease in FHR associated with uterine contraction Gradual decrease: onset to nadir ≥ 30 sec Abrupt decrease: onset to nadir < 30 sec

Recurrent decelerations: Occur with ≥ 50% of contractions

Intermittent decelerations: Occur with < 50% of contractions

NICHD: Classifying Decelerations

Onset Shape Nadir

Early Gradual Symmetrical Matches UC peak

Variable Abrupt Asymmetrical

≥ 15 bpm lasting ≥ 15 sec but < 2 min

Late Gradual Symmetrical After UC peak

NICHD: Deceleration Features NOT Defined

Slow return to baseline Biphasic decelerations ‘Reflex’ tachycardia following variable

decelerations (“shoulders” or “overshoots”) FHR fluctuations in the trough of the deceleration Mild, moderate and severe

NICHD: What to Call the Categories?

Three-tier classification system:

Systems agree on the really good and really bad

Middle group requires ongoing surveillance

“Good”: Normal? Reassuring? Non-pathological?

Middle: Intermediate? Indeterminate? Undetermined significance?

“Bad”: Abnormal? Non-reassuring? Pathological?

After Extensive Discussion…

Initial conference decision: Normal: “reassuring” Equivocal: requires ongoing assessment / evaluation

Abnormal: requires urgent action

Concerns about implied action necessary (e.g. equivocal requires intervention)

Final classification system: Category I Category II Category III

NICHD 3 Tier Interpretation System:Category I

Category I FHR tracings must exhibit ALL of the following features: Baseline rate:110-160 bpm Baseline FHR variability: moderate Late or variable decelerations: absent Early decelerations: present or absent Accelerations: present or absent

Category III FHR tracings include EITHER: Absent FHR variability with any

ONE of the following: Recurrent late decelerations Recurrent variable decelerations Bradycardia

Sinusoidal Pattern for ≥ 20 min

NICHD 3 Tier Interpretation System:Category III

NICHD: Category III

Category II includes all FHR tracings not categorized as Category I or Category III

Represent an appreciable majority of those encountered in clinical care Moderate variability with bradycardia Minimal FHR variability Absent variability with no recurrent decels Recurrent variables with moderate variability Recurrent late decelerations with moderate

variability

NICHD 3 Tier Interpretation System:Category II

NICHD: Category II

NICHD: Category II

NICHD FHR Categories: Meaning and Action

Category I = “normal” Strongly predictive of normal acid base status Follow in a ‘routine manner’

Category III = “abnormal” Predictive of abnormal acid base status Prompt evaluation required Resolve the pattern (corrective measures,

delivery)

Category II: “indeterminate” Not predictive of abnormal acid base

status Inadequate evidence to classify either as

Category I or as Category III Requires continued re-evaluation and

surveillance, consideration of additional testing and non-surgical interventions

NICHD FHR Categories: Meaning and Action

NICHD: Interventions for Category II and III Tracings Acceleration testing:

Fetal scalp sampling Scalp stimulation (digital or Allis clamp) Vibroacoustic stimulation

Stop oxytocin Cervical exam: Cord prolapse? Rapid

dilation? Descent of head?ACOG Practice Bulletin 2009

Change maternal position Assess and treat hypotension Assess for uterine tachysystole

Maternal oxygen Tocolytic therapy

Consider amnioinfusion for recurrent variable decelerations

ACOG Practice Bulletin 2009

NICHD: Interventions for Category II and III Tracings (cont.)

Abnormal despite interventions deliver

NICHD: Persistent Category III

Implementation of 3-tier system:

Recommend starting now Description of contractions Be more descriptive with Category II tracings

(include baseline, variability, accelerations, decelerations, trends over time, and contractions)

Education Multidisciplinary

Research Directions

Observational studies of Category II tracings Correlate to acid base status, and to

perinatal and pediatric outcomes Computerized EFM assessment

Analysis of FOX tracings Education / dissemination

New Guidelines for Fetal Heart Rate Monitoring: How to Adopt Them

Mary E. D’Alton, MDWillard C. Rappleye Professor

Chair, Department of Obstetrics and Gynecology

Columbia University College of Physicians and Surgeons

New York, New York

All the possibilities of modern medicine