Impacted fetal head at cesarean delivery.

Purpose: Impacted fetal head (IFH) can be defined as the deep engagement of the fetal head in the maternal pelvis at the time of cesarean delivery that leads to its difficult or impossible extraction with standard surgical maneuvers. In this narrative review, we aimed to ascertain its incidence, risk factors, management and complications from the perspective of the anesthesiologist as a multidisciplinary team member.

Methods: Databases were searched from inception to 24 January 2023 for keywords and subject headings associated with IFH and cesarean delivery.

Results: IFH has an incidence of 2.9-71.8 % in emergency cesarean section. Maternal risk factors are advanced cervical dilatation, second stage of labor and oxytocin augmentation. Anesthetic and obstetric risk factors include epidural analgesia and trial of instrumental delivery and junior obstetrician, respectively. Neonatal risk factors are fetal malposition, caput and molding. Current evidence indicates a lack of confidence in the management of IFH across the multidisciplinary team. Simple interventions in IFH include lowering the height or placing the operating table in the Trendelenburg position, providing a step for the obstetrician and administering pharmacological tocolysis. Maternal complications are postpartum hemorrhage and bladder injury while neonatal complications include hypoxic brain injury, skull fracture and death. Surgical complications are reviewed to remind the anesthesiologist to anticipate and prepare for potential problems and manage complications in a timely manner.

Conclusion: The anesthesiologist has a fundamental role in the facilitation of delivery in IFH. We have proposed an evidence based management algorithm which may be referred to in this emergency situation.