The June 2023 RCOG paper provides an algorithm on how to manage this obstetric emergency.
- Anticipation of IFH is important where there are clinical features including a low position of the fetal head, the malposition of the fetal head (for example the baby is in a “back to back” position), advanced cervical dilatation and a failed assisted vaginal birth.
- If IFH is anticipated then clinical staff can prepare for the caesarean section in a better way so that it’s ensured senior and experienced staff are present, attempts to move the fetal head are made pre making an incision and the anaesthetist has GTN spray ready to reduce uterine contractions.
- Diagnosis of impacted fetal head.
- Declaration of an emergency ensures clear communication and calmer consideration of how to manage a stressful emergency situation.
- Neonatal staff can be called ready for neonatal resuscitation if required.
When impacted fetal head is identified, there are a number of ways to manage it.
What is abdominal cephalic disimpaction?
This is when the obstetrician places their hand into the abdominal incision to access the fetal head by cusping the fetal head anteriorly against the maternal pubic symphysis bone. This is a very skilled technique whereby the surgeon needs to achieve the safe flexion of the fetal head to elevate the head sufficient to enable delivery. If this fails then the ‘push technique’ should be attempted:
What is the push technique in impacted fetal head?
If on caesarean section the head cannot be delivered abdominally the obstetrician or midwife can attempt to delivery the fetal head by placing their hand into the vagina to gently attempt to disengage the head from the pelvis and push the impacted fetal head up into the uterus to allow for caesarean delivery.
This in itself is quite high-risk procedure and requires excellent communication between the surgeon and the medic pushing on the fetal head. There is a risk of not only excessive pressure causing skull injury to the fetus but also the risk of worsening the impaction by causing the head to become more deflexed and embedded.
What is a Reverse Breech extraction?
Having considered inverted T or J incision of the abdomen, a reverse breech extraction involves the obstetrician inserting their hand into the upper section of the uterus in order to grasp the fetal foot or feet – this is followed by steady traction of the fetal feet towards the mother’s feet to flex the fetal waist and deliver first the legs and then buttocks, followed by the fetal head.
What is the reverse Patwardhan technique?
This is a modification of the reverse breech extraction, where the arms rather than the feet are delivered first. This is not a recommended technique in the UK.