Foetal monitoring

Question 1

How would you monitor the foetus of a low risk mother?

Answer 1

Intermittent auscultation (sonicaid/doppler)

monitor baby’s heart rate after every contraction (if mother is low risk)

Question 2

How would you monitor the foetus of a high-risk mother in labour?

Answer 2

Continuous monitoring eg. CTG cardiotocograph

Bottom probe picks up heart rate (top trace)

Top probe picks up contractions (bottom trace)

Every time a woman feel foetal movement, presses a button

Question 3

What are some examples of high-risk situations in which you might use CTG cartiotocography?

Answer 3

Any pregnancy which is not low risk eg.

Oxytocin infusion

Meconium stained liquor

Multiple pregnancy

Intra-uterine growth restriction (IUGR)

Abnormality on intermittent auscultation

Question 4

When might you use a foetal scalp electrode over an abdominal transducer?

Answer 4

Poor contact with abdo transducer

High BMI

Twins (can’t decipher between babies)

Baby is too active

Abdo scarring (sound waves don’t go through very well)

Question 5

What is the baseline foetal heart rate?

Answer 5

100-160 bpm

Question 6

What is an acceleration - is that a good or a bad thing?

Answer 6

Rise of >15bpm for 15 seconds

good - indicates movement

Question 7

What is a deceleration - is this a good or a bad thing?

Answer 7

drop of >15bpm for 15 seconds

bad (if late). Not concerning if early

Question 8

What are the benefits of CTG?

Answer 8

reduced rate of neonatal seizures

increases intervention rate

Question 9

What are the limits/drawbacks of CTG?

Answer 9

No clear benefit of cerebral palsy and perinatal death

Question 10

What should you do if you are worried about a CTG?

Answer 10

Change maternal position (to left lateral)

Give fluids - ?dehydrated (less perfusion to baby)

Fetal scalp stimulation

Foetal blood sample (if concerned and delivery is not imminent)

Deliver

Question 11

How many centimetres dilated must someone be before foetal blood sample can be taken?

Answer 11

3cm

Question 12

Why are foetal blood samples useful?

Answer 12

Immediate and accurate result re. baby’s welfare

Measures foetal pH (indicative of hypoxaemia)

Question 13

What doe foetal blood samples measure?

Answer 13

Foetal pH (indicative of hypoxaemia)

Question 14

What does a foetal pH of >7.25 indicate?

Answer 14

normal - baby is not hypoxaemic

Question 15

What does a foetal pH of 7.20-7.25 indicate?

Answer 15

borderline ?hypxoaemic

Question 16

What does a foetal pH <7.20 indicate that you should do?

Answer 16

DELIVER

Question 17

What is the mnemonic for interpreting CTGs?

Answer 17

DR C BRAVADO

DR: determine risk - why is woman on CTG?

C: contractions

BR: baseline rate

A: accelerations

VA: variability

D: decelerations

O: Overall impression eg. normal/reassuring, non-reassuring/abnormal

Question 18

What should happen to the baby’s heart rate when it moves in the womb?

Answer 18

HR should increase (acceleration)

Question 19

How are contractions classified?

Answer 19

per 10 minutes

Question 20

How do contractions present on CTG?

Answer 20

Peaks

Question 21

What is the desired rate of contractions on a CTG during labour?

Answer 21

4-5:10

Question 22

How do you measure the intensity of contractions?

Answer 22

Mother will tell you

palpate

Question 23

Why is a flat trace a concern in a CTG?

Answer 23

shows no variability (therefore shows damage to PONS and lack of sympathetic/parasympathetic competition)

Question 24

What is the ideal variability on a CTG?

Answer 24

> 5bpm or more

Question 25

What do accelerations show?

Answer 25

Foetal movement

Question 26

What is a deceleration on a CTG?

Answer 26

>15 beats for >15 seconds

Question 27

What can decelerations indicate?

Answer 27

placental insufficiency

Question 28

When do LATE decelerations occur?

Answer 28

have to occur after contraction BUT HAVE TO ALL BE EXACTLY THE SAME TIME AFTERWARDS TO BE CLASSED AS LATE

Question 29

What is a typical variable deceleration?

Answer 29

deceleration of <60 beats for <60 seconds

Question 30

What is an atypical variable deceleration?

Answer 30

deceleration of >60 beats for >60 seconds (profound and broad drops)

Question 31

What is the problem with the false-positive rate in CTG?

Answer 31

can mean that some interventions occur unnecessarily and can cause distress for a mother that was otherwise not needed

Question 32

Why is Left lateral position the best position for a mother?

Answer 32

takes pressure of IVC, therefore allows better blood supply to baby

Question 33

What is a more accurate test of baby's hypoxia level than a CTG?

Answer 33

Foetal blood sample

Question 34

What can cause an increase in heart rate in a baby? (other than foetal movements)

Answer 34

foetal distress infection maternal dehydration (less blood volume going to baby)

Question 35

How can an epidural effect foetal heart rate? What should you do about this?

Answer 35

tachycardia/bradycardia - any changes to CTG because: Maternal BP drops Less blood to baby baby becomes distressed First thing to do: Left lateral position 1L of fluids STAT.

Question 36

What foetal heart rate is needed to maintain cerebral perfusion?

Answer 36

100 for 50% of time