Prolonged deceleration in a freestanding midwife-led birth centre at 41+5 weeks
Ruth is 30 years old, G2P1, and labours at home at 41+5 weeks. She transfers to a freestanding midwife-led birth centre at 5 cm because she wants pain relief and the pool at home is not working. Membranes ruptured spontaneously two hours ago with clear liquor. Intermittent auscultation has been normal. Because progress has slowed, a CTG is started. The trace shows a baseline of 160 beats/min, variability of 5 beats/min, no accelerations, and a deceleration to 70 beats/min that began four minutes ago and has lasted three minutes; it is now recovering to 150 beats/min. Ruth’s pulse is 92 beats/min, blood pressure 110/70 mmHg, temperature 37.4°C. She has not had an epidural or oxytocin. There is no obstetric unit on site; ambulance transfer takes 30–40 minutes.
1. Interpret the CTG using a structured framework and outline your immediate management.
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Structured interpretation (DR C BRAVADO)
- Define risk: prolonged pregnancy at 41+5, first stage at 5 cm, no epidural or oxytocin, clear liquor. She is in a midwife-led unit without onsite obstetric or neonatal support.
- Contractions: not described on the trace; I would document frequency and duration and palpate the uterus.
- Baseline rate: 160 beats/min, which is fetal tachycardia.
- Variability: 5 beats/min, which is reduced.
- Accelerations: absent.
- Decelerations: a single prolonged deceleration to 70 beats/min lasting three minutes, with recovery to 150 beats/min.
- Overall impression: this is not a normal trace. A prolonged deceleration with fetal tachycardia and reduced variability is pathological and requires urgent action.
Immediate management
- Call for help: second midwife, ambulance, and the on-call obstetric team by phone.
- Reposition Ruth to the left lateral position and give her oxygen only if she is hypoxic; do not use oxygen routinely for fetal distress.
- Perform a vaginal examination to exclude cord prolapse and check cervical dilatation. If cord prolapse is present, elevate the presenting part and transfer immediately.
- Check Ruth’s pulse and blood pressure; maternal tachycardia can be mistaken for fetal tachycardia.
- Gain IV access if possible and take bloods, but do not delay transfer.
- Stop any contraction-stimulating drugs - none are running here.
- Document the time of each action and the trace, and keep the CTG printout.
The key reasoning is that a three-minute deceleration is a prolonged deceleration, not a typical variable deceleration, and the combination with tachycardia and reduced variability raises concern about fetal hypoxia.
2. What is your decision about transfer, and how would you communicate it to Ruth and her partner?
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Decision I would arrange immediate transfer to the obstetric unit. The trace is pathological, there is no onsite obstetric or neonatal team, and a recurrence could become an emergency during the 30–40 minute journey. Waiting to see whether the trace normalises would be unsafe in this setting.
Communication
- I would be honest but calm: ‘The baby’s heart rate pattern has changed in a way that worries us. We need to move to the hospital where the obstetric and neonatal teams can care for you and the baby if needed.’
- I would explain that the deceleration recovered, but that the pattern is not normal and the risk of another, longer deceleration is why we cannot stay.
- I would involve her partner in the practical arrangements: ambulance, notes, placenta if delivered, and who will travel with her.
- I would ask about her preferences, such as position for transfer and whether she wants entonox, but I would not offer choices that delay transfer.
- I would document her consent to transfer, her understanding, and any questions she asks.
During transfer I would continue intermittent auscultation or CTG if equipment allows, stay with her, monitor for further decelerations, and pre-alert the receiving unit with the trace findings and estimated arrival time.
3. If a further prolonged deceleration occurs during transfer, what would you do with the resources available?
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I would treat it as an obstetric emergency. I would call ahead to the receiving unit and the ambulance control, state that there is a prolonged deceleration, and ask for the fastest possible arrival. In the ambulance I would:
- Reposition Ruth to the left lateral position and encourage her not to push if she is not fully dilated.
- Check for cord prolapse if membranes are ruptured and a vaginal examination is feasible; if prolapse is found, elevate the presenting part with a hand or fill the bladder if trained and equipped, and continue urgent transfer.
- Give oxygen only if maternal hypoxia is present; routine oxygen for fetal distress is not recommended.
- Maintain IV access if already gained.
- Monitor maternal pulse and blood pressure and observe for signs of shock.
- Keep the CTG record and note the time, duration, and recovery of the deceleration.
I would not attempt fetal blood sampling or tocolysis in a moving ambulance. The priority is rapid transfer with maternal positioning and continuous observation. I would explain to Ruth what is happening and why, and document the events and advice received from the receiving unit.