Intrapartum Care - Cardiotocography (CTG)

Question 1

What is Cardiotocography?

Answer 1

Electronic foetal monitoring - measuring the foetal heart rate and uterine contractions.

Question 2

How are CTGs recorded?

Answer 2

2 Doppler US Transducers placed on the abdomen : one above the foetal heart (foetal heartbeat) and one near the uterine fundus (tension - uterine contractions).

Question 3

Indications of Continuous CTG Monitoring (8).

Answer 3

1. Sepsis.
2. Maternal Tachycardia (>120).
3. Significant Meconium.
4. PET.
5. Fresh APH.
6. Delay in Labour.
7. Use of Oxytocin.
8. Disproportionate Maternal Pain.

Question 4

Key Features of a CTG (5).

Answer 4

1. Contractions (Uterine Contractions in 10 Minutes).
2. Baseline Foetal Heart Rate.
3. Variability (Foetal Heart Rate).
4. Accelerations (Spikes of Foetal Heart Rate).
5. Decelerations (Drops of Foetal Heart Rate).

Question 5

What do Contractions indicate? (2)

Answer 5

Activity of labour :

1. Too Few - Failure to Progress.
2. Too Many - Uterine Hyperstimulation : Foetal Compromise.

Question 6

What do Accelerations indicate?

Answer 6

Healthy foetus.

Question 7

What are the 3 Types of Baseline Foetal Heart Rate?

Answer 7

1. Reassuring : 110-160.
2. Non-Reassuring : 100-109 or 161-180.
3. Abnormal : Below 100 or Above 180.

Question 8

Aetiology of Baseline Bradycardia.

Answer 8

1. Increased Foetal Vagal Tone.

2. Maternal B-Blocker Use.

Question 9

Aetiology of Baseline Tachycardia.

Answer 9

1. Maternal Pyrexia.
2. Chorioamnionitis.
3. Hypoxia.
4. Prematurity.

Question 10

Aetiology of Loss of Variability.

Answer 10

1. Prematurity.

2. Hypoxia.

Question 11

What are the 3 Types of Variability of Foetal Heart Rate?

Answer 11

1. Reassuring : 5-25.
2. Non-Reassuring : Less than 5 for 30-50 Minutes or More than 25 for 15-25 Minutes.
3. Abnormal : Less than 5 for 50 Minutes or More than 25 for over 25 Minutes.

Question 12

What do Decelerations indicate?

Answer 12

Foetal Heart Rate drops in response to hypoxia.

Question 13

What are the 4 Types of Decelerations?

Answer 13

1. Early.
2. Late.
3. Variable.
4. Prolonged.

Question 14

What are Early Decelerations? (2)

Answer 14

1. Gradual dips and recovering in HR that correspond with uterine contractions.
2. Lowest Point of Deceleration corresponds to peak of contraction.

Question 15

Aetiology of Early Decelerations.

Answer 15

Normal - not pathological - uterus compresses head of foetus which stimulates vagus nerve to slow HR.

Question 16

What are Late Decelerations? (3)

Answer 16

1. Gradual falls in HR that start after uterine contractions begin.
2. Delay (more than 30 seconds) between uterine contractions and deceleration.
3. Lowest point of Deceleration occurs after peak of contraction.

Question 17

Aetiology of Late Decelerations (3).

Answer 17

Hypoxia in the foetus :

1. Excessive Uterine Contractions.
2. Maternal Hypotension.
3. Maternal Hypoxia.

Question 18

What are Variable Decelerations? (3)

Answer 18

1. Abrupt Decelerations unrelated to uterine contractions.
2. Fall of more than 15BPM from baseline.
3. Lowest point of Deceleration occurs within 30 seconds and lasts less than 2 minutes.

Question 19

Aetiology of Variable Decelerations.

Answer 19

Intermittent compression of the umbilical cord, causing foetal hypoxia.

Question 20

What can make Variable Decelerations more reassuring?

Answer 20

Brief accelerations before and after the deceleration - ‘shoulders’.

Question 21

What are Prolonged Decelerations? (2)

Answer 21

1. Decelerations lasting between 2 minutes and 10 minutes.

2. Drop of more than 15BPM from baseline.

Question 22

Aetiology of Prolonged Decelerations.

Answer 22

Compression of the umbilical cord - foetal hypoxia.

Question 23

What can make Deceleration findings reassuring? (3)

Answer 23

1. No Decelerations.
2. Early Decelerations.
3. Less than 90 Minutes of Variable Decelerations with no Concering Features.

Question 24

What can make Deceleration findings non-reassuring? (2)

Answer 24

1. Regular Variable Decelerations.

2. Late Decelerations.

Question 25

What can make Deceleration findings abnormal?

Answer 25

Prolonged Decelerations.

Question 26

What are the 4 Categories of a CTG?

Answer 26

1. Normal.
2. Suspicious (Single Non-reassuring Feature).
3. Pathological : 2 Non-Reassuring Features or 1 Abnormal Feature.
4. Need for Urgent Intervention : Acute Bradycardia or Prolonged Deceleration of More than 3 Minutes.

Question 27

What are CTGs categorised on? (3)

Answer 27

1. Baseline Rate.
2. Variability.
3. Decelerations.

Question 28

Management Options for Adverse CTG.

Answer 28

1. Escalation.
2. Further Assessment for Causes.
3. Conservative Interventions e.g. Reposition Mother, IV Fluids (Hypotension).
4. Foetal Scalp Stimulation (Acceleration in response is reassuring).
5. Foetal Scalp Blood Sampling (Foetal Acidosis).
6. Delivery (Instrumental or C-Section).

Question 29

Management of Foetal Bradycardia (4).

Answer 29

Rule of 3s :

1. 3 Minutes - Call for Help.
2. 6 Minutes - Move to Theatre.
3. 9 Minutes - Prepare for Delivery.
4. 12 Minutes - Deliver the Baby by 15 Minutes.

Question 30

What is a Sinusoidal CTG?

Answer 30

A rare pattern indicating severe foetal compromise (similar to a sine wave, with smooth regular waves up and down with an amplitude of 5-15 BPM).

Question 31

Aetiology of Sinusoidal CTG.

Answer 31

Severe foetal anaemia e.g. Vasa Praevia.

Question 32

What is DR C BRAVADO?

Answer 32

1. DR - Define Risk (based on Individual Woman and Pregnancy).
2. C - Contractions.
3. B RA - Baseline RAte.
4. V - Variability.
5. A - Accelerations.
6. D - Decelerations.
7. O - Overall Impression.