Lifting the Impacted Fetal Head; the Fetal Pillow and Tydeman Tube Trial

An impacted fetal head is a common complication encountered in 11% of all emergency caesarean sections and 65% of those performed at full dilatation. A recent UK Obstetric Surveillance Survey (UKOSS) highlighted significant maternal and neonatal complications secondary to an impacted fetal head, with 3% of babies dying or suffering a severe injury, and 6.1% of mother's requiring admission to intensive care, emphasizing the need to evaluate techniques and new devices to aid delivery. NHS resolution's early notification scheme implicated an impacted fetal head as a contributing factor in 9% of all severe neonatal brain injuries in 2019. There is no consensus amongst clinicians on the best management of an impacted fetal head, and with exponentially rising rates of intrapartum caesarean sections, improved management tools are urgently required.

This study will compare maternal and neonatal outcomes using two devices to aid delivery of an impacted fetal head at full dilatation caesarean section (FDCS)- the Tydeman Tube, a new UK Conformity Assessed (UKCA) and European Conformity (CE) marked device, and the Fetal Pillow, an existing CE marked device used commonly in clinical practice. There will be a separate observational sub study evaluating the use of the Tydeman Tube for managing an impacted fetal head at 7-9cm dilated. The study will also explore the acceptability of both devices to women and clinicians using postnatal questionnaires.

Participants will be all women requiring a full dilatation caesarean section who meet eligibility criteria. The study will be run in two consecutive arms - firstly, obstetricians and midwives will be trained to use the Fetal Pillow. The Fetal Pillow will then be introduced into clinical practice for 3-6 months. Following this the Fetal Pillow will be removed from clinical practice. Midwives and Obstetricians will then be trained to use the Tydeman Tube, which will be introduced into clinical practice for a further 3-6 months. During the Tydeman Tube arm of the trial, women undergoing caesarean section at 7-9cm who are found to have an impacted fetal head unexpectedly at the time of caesarean section are eligible for the observational sub study. If the operating surgeon believes the Tydeman Tube is required for the clinical situation then it may be used.

The trial is a prospective observational comparison trial with an additional observational sub study. The results of this study will be used to improve understanding on the best management techniques for an impacted fetal head.