FETAL MONITORING

GOALS

1. To have standardized terminology and approach in interpretation of CTG

2. To identify abnormal CTG and appropriate intervention

3. Risk management and documentation

MODALITIES IN SGH…

Intermittent auscultation (Pinard stetoscope)

Electronic FHR monitoring (Daptone)

Cardiotocograph (CTG)- external or internal

Fetal scalp blood sampling (pH testing)

1. FETAL STETHOSCOPE…

• 17th century - 1818 Francis-Isaac• Professor John Ferguson described fetal heart sound in 1827

Hohl fetal stethoscope Depaul fetal stethoscope

FREQUENCY OF AUSCULTATION

2.DAPTONE..

Doppler principle to produce excellent external traces

FREQUENCY OF AUSCULTATION

3. CTG…

DEFINITION (CTG) is a technical means of recording (-graphy) the fetal heartbeat (cardio-) and the uterine contractions (-toco-) during pregnancy

The machine used to perform the monitoring is called a cardiotocograph (CTG), more commonly known as an electronic fetal monitor (EFM)

Ultrasound Doppler technology has produce excellent quality external traces

Corometric 170 series

Avalon FM 20

Oxford-Sonicaid Meridian fetal monitor

ADVANTAGES FHR & contraction can

be monitored & recorded at the same time

Reduce rates of seizure in newborn

DISADVANTAGES Prevent mother from moving Unable to change position Increase interventions

(instrumental deliveris or C-sec)

TYPESEXTERNAL CTG An ultrasound

transducer over the abdomen that will pick up the baby's heartbeat. The heartbeat will be recorded continuously on a paper strip.

Tocogram- a pressure gauge that measures the frequency of your contractions.

INTERNAL CTG This method can only

be used if membranes (fore-waters) and your cervix have ruptured either spontaneously or artificially.

An electrode is placed on the baby’s scalp to directly monitor the fetal heart rate. An electrode is called a fetal scalp electrode (FSE)

The length of the CTG strip depends on the paper speed. In the UK it is usually 1cm/min.

Each vertical division on the paper is 1cm and therefore 1 min.

SALSO 2015

ELECTRICAL FETAL MONITORING: TERMINOLOGY

A=Fetal heart rateB=Movement by motherC=Fetal movementD=Contraction

Twin 1

Twin 2

Tocogram

DR DEFINE RISKC CONTRACTIONBR BASELINE HEART

RATEA ACCELARATIONVA VARIABILITYD DECELARATIONO OVERALL

INTERPRETATION OF CTG: DR C BR A VA DO

The process of birth is the most dangerous journey any individual undertakes

Assess from the history and examination either low risk or high risk pregnancy

Admission CTG performed, then intermittent ascultation vs continuous monitoring

1. DR = DEFINE RISK

*ALL ANTENATAL PATIENT CAME TO LABOUR ROOM WILL HAVE AN ADMISSION CTG AT LEAST 20 MINS TRACINGRISK CTG MONITORINGLOW - Intermittent tracing 2-4hly

- Continous CTG is unnecessary

MODERATE - Intermittent CTG trace to be decide by registra or specialist

- Frequency & length of CTG tracing depends on individual case & previous trace

HIGH - Intermittent CTG trace to be decide by registrar or specialist

- Continous CTG may be needed

Assess contraction pain from the tocogram- quantifying the number of contractions present in a 10-minute window

There are several factors used in assessing uterine activity. Frequency Duration

Normal- less than or equal to 5 contractions in 10 minutes, averaged over a 30-minute window

Tachysystole- more than 5 contractions in 10 minutes, averaged over a 30-minute window

2. C = CONTRACTION

SALSO 2015

CONTRACTIONS

Level of the fetal heart rate when this stable with accelerations and decelerations excluded. Determined over a period of 5 or 10 min and expressed in bpm.

Normal range is 100-160bpm.

3. BR = BASELINE FETAL HEART RATE

BASELINE (BEATS/MIN)

Normal/reassuring

Non-reassuring

Abnormal

100-160 161-180 >180 or <100

Is it fetal or maternal?

Always use the fetal stethoscope before applying the machine

Tachycardia – is a baseline heart rate of > 160bpm

Causes?

Bradycardia- baseline fetal heart rate < 100bpm

* A stable basline fetal heart rate between 90-99 bpm with normal baseline variability may be a normal variation

Transient increase in heart rate of 15bpm or more and lasting 15s or more.

The recording of at least 2 accelerations in a 20 min period is considered a reactive trace

Accelerations are the hallmark of fetal health.

4. A = ACCELERATION

NICE GUIDELINES 2014 Acceleration is not a feature to categorise CTG Fetal heart rate accelerations is generally a sign

that unborn baby is healthy Abscence of accelerations in an otherwise normal

CTG does not indicate acidosis If FBS is indicated and sample cannot be

obtained,but scalp stimulation results in fetal heart rate acceleration,decide whether to continue labour or expedite the birth in light of the clinical circumstances and in discussion with the woman

Baseline varies within a particular band width excluding accelerations and decelerations. It indicates the integrity of the autonomic nervous system Silent , 0-

5bpm

Reduced, 5-10bpm

Normal, 10-25bpm

Saltatory, >25bpm

5. VA = VARIABILITY

BASELINE VARIABILITY

Normal/reassuring

Non- reassuring

Abnormal

5 or more <5 for 30-90min <5 for > 90min*Intermittent period of reduced baseline

variability are normal, especially during periods of

“sleep”

Reduced baseline variability:The commonest reasons : sleep phase of the FHR cycle

• Hypoxia• prematurity• tachycardia• drugs (sedatives, antihypertensive acting on CNS, anaesthetics)• Fetal anaemia (Rhesus disease or fetomaternal haemorrhage )• congenital malformations• cardiac arrhythmias• fetal infection

Transient episode of slowing of the heart rate below the baseline level of > 15bpm and lasting 15s or more

6. D = DECELERATION

Early deceleration in 2nd stage of labour

TYPE 1 OR EARLY..

Onset of deceleration consistent with contraction

The onset of deceleration after the contraction. Late deceleration in 2nd stage of labour

TYPE 2 OR LATE….

Vary in shape, size and in timing with respect to each other.

A manifestation of compression of the umbilical cord

VARIABLE

Variable deceleration

Normal/reassuring

Non-reassuring

Abnormal

None or early Variable deceleration dropping from baseline less than 60 beats AND taking less than 60 sec to recover Present over 90minOccuring over 50% of contraction

Non-reassuring variable deceleration Still observed 30min after starting conservative measures

Variable deceleration dropping from baseline >60 bpm OR taking > 60sec to recoverPresent for up to 30minOccuring over 50% of contractions

Bradycardia or single prolonged deceleration lasting 3min or more

Late deceleration present for up to 30minOccuring over 50% of contractions

Late deceleration present for>30 minOccuring over 50% of contractionDo not improve with conservative measures

Decelerations (variable or late) accompanied by fetal tachycardia or reduced baseline variability

Take action sooner than 30min

Normal/Reassuring

Non-reassuring

Abnormal

7. O=OVERALL CATEGORISATION OF FHR TRACE

4 FEATURES OF CTG

1) Acceleration – no longer include

2) Baseline fetal heart rate3) Baseline variability4) Deceleration

Used to categorise CTG

CTG catogories

Normal /reassuring All 3 features are normal

Non-reassuring 1 non-reasuring featureAND 2 normal/reassuring features

• Conservative measures

Abnormal(need for conservative measures AND further testing)

1 abnormal featureOR 2 non-reasuring features

• Conservative measures• Offer FBS or Expedite birth if FBS cannot be obtained and no accelerations are seen as a result of scalp stimulation

Abnormal(need for urgent intervention)

Bradycardia or single prolonged deceleration with baseline below 100bpm persisting 3min or more

• Start Conservative measure

• Prepare for urgent birth• Expedite birth if persist

for 9min• If heart rate recovers

before 9 min, reassess decision to expedite birth in discussion with the woman

OVERALL CARE Do not make any decision about woman’s care in labour on the

basis of CTG findings alone

Make a documented systematic assessment of the condition of woman and the unborn baby hourly or more frequently if there is concern

HOW TO MANAGE??

DEPENDS ON VARIOUS FACTORS 1.Severity of abnormal trace 2.Antenatal risk 3.Patient’s age & parity 4.How advance she is in labour 5.Progress of labour 6.Colour of liquour 7.Patient’s opinion

CTG GOALS DO DON’TRecurrent Type 2 decelerations

Improve placenta perfusion

-Left lateral position-Reducing frequency of uterine contractions

-Administer O2-IV Fluid bolus

Prolonged deceleration or bradycardia

Improve placenta perfusion

-Tocolytic agents

Minimal or absent variability

Improve placenta perfusion

-Lateral position-Fetal stimulation

Hyperstimulation Reduce uterine contractility

-Stop oxytocin-Tocolytic agents

Recurrent variable deceleration

Reduce cord compression

-Maternal position

Amnioinfussion

** In an emergency setting- acceptable time for decision to the delivery of the baby is 30 minutes

SECOND STAGE CTGMost of the time CTG is abnormalEarly deceleration or variable

deceleration is acceptableWhich CTG changes require

interventions? Prolonged bradycardia Reduced variability

4. FETAL SCALP BLOOD SAMPLING

Fetal scalp PH testing is essentially an invasive vaginal procedure performed when a woman is in active labour to determine if the baby is getting enough oxygen

If possible should be performed before a decission of C-Sec is made where the CTG changes are not conclusive or suspicious

RESULT…pH RESULT ACTIONNORMAL 7.25-7.35 REPEAT IF

ABNORMALITY PERSIST

BORDERLINE 7.20-7.25 REPEAT TEST EVERY 30 MINS TILL DELIVERY IF VAGINAL DELIVERY IS EXPECTED SOON

ABNORMAL < 7.20 EXPEDITE DELIVERY

RISKS Bleeding from puncture site Infection Bruising on fetal’s scalp

CONTRAINDICATIONS Infections- hep C or HIV Thrombocytopenia Non cephalic presentation Prematurity <34 weeks

RISK MANAGEMENT

Proper documentation in case notes- date, time, signature

Document paired cord blood gases & accurate Apgar Score

Photocopy the CTG and store properly Frequent training of staff

QUESTIONS??