CTG

Question 1

What is the normal range for FHR baseline?

Answer 1

110-160

Question 2

What is variability?

Answer 2

6 to 25 bpm above or below baseline?

Question 3

What makes an accelerations?

Answer 3

15 bpm above baseline for 15 seconds

Question 4

What makes a deceleration?

Answer 4

15 bpm below the baseline

Question 5

What is an early deceleration?

Answer 5

A deceleration that;
- Occurs usually between 4 to 8 cm
- with contractions
- Sleep phase
- Head compression (intracranial pressure)

Question 6

What is a variable deceleration?

Answer 6

A deceleration that;
- Due to cord compression
- Usually V shaped
- Vary in regularity and depth

Question 7

What makes a variable deceleration a complicated variable deceleration?

Answer 7

Variable + abnormality
- Rising baseline
- Reduced/absent baseline variability
- Slow return to baseline after contraction
- Post deceleration smooth overshoots
- Hyperstimulation

Question 8

What is a prolonged deceleration? Actions?

Answer 8

• 90 second to 5 minutes
• Environmental
• Action = move mother, turn syntocinon off and call for help.

Question 9

What is a Brady? Actions?

Answer 9

• Decelerations for more than 5 minutes
• Environmental
• Actions = call for help, stop synotcinon.

Question 10

What are late decelerations? Actions?

Answer 10

• Lates have mates
• Indicates hypoxia
• Action = call a code

Question 11

What is a sinusoidal trace?

Answer 11

• Oscillating pattern that is smooth and regular
• Typically reflective of severe anaemia

Question 12

What is tachysystole?

Answer 12

5 active contractions in 10 minutes without FHR abnormalities

Question 13

What is uterine hypertonus?

Answer 13

Contractions lasting more than 2 minutes (or) contractions occurring within 60 seconds of each other

Question 14

What is hyperstimulation?

Answer 14

Either tachysystole or uterine hypertonus WITH the presence of FHR abnormalities

Question 15

What are the antenatal indications for CTG monitoring?

Answer 15

• Abnormalities of maternal serum screening associated with an increased risk of poor perinatal outcomes
  e.g. low PAPP-A <0.4MoM.
• Antepartum haemorrhage
• Breech presentation
• Decreased fetal movements
• Diabetes where medication is indicated or poorly controlled, or with fetal macrosomia
• Essential hypertension or pre-eclampsia
• Known fetal abnormality which requires monitoring
• Maternal age greater than or equal to 42
• Multiple pregnancy
• Oligohydramnios or polyhydramnios
• Other current or previous obstetric or medical conditions which constitute a significant risk of fetal
  compromise e.g. cholestasis, isoimmunisation, substance abuse
• Prior uterine scar / caesarean section
• Prolonged pregnancy >42 weeks gestation
• Prolonged rupture of membranes (>24 hours)
• Suspected or confirmed intrauterine growth restriction

Question 16

What are the intrapartum indications for CTG monitoring?

Answer 16

• Induction of labour with prostaglandin / oxytocin
• Abnormal auscultation or CTG
• Oxytocin augmentation
• Regional analgesia e.g. epidural or spinal, paracervical block*
• Abnormal vaginal bleeding in labour
• Maternal pyrexia greater than or equal to 38°C
• Meconium or blood stained liquor
• Absent liquor following amniotomy
• Active first stage of labour >12 hours (i.e. after diagnosis of labour)
• Active second stage (i.e. pushing) >1 hour where birth is not imminent
• Preterm labour less than 37 completed weeks1
• Tachysystole
• Uterine hypertonus
  fetal heart rate changes
• Uterine hyperstimulation