Ex-utero Intrapartum Treatment (EXIT) – also known as ‘operation on placental support’ (OOPS) and airway management on placental support (AMPS)- is a rare surgical procedure, [1] performed to allow surgical correction of foetal airway patency whilst still being perfused by placenta. It consists of partial externalisation of the foetus from the uterine cavity during delivery, while maintaining placental circulation eliminating concerns for hypoxia. Currently in the UK, the EXIT procedures are undertaken in specialised centres, these include St. Georges Hospital London and Royal Manchester Children Hospital. In this article, Dr Sher Mohammad and other discuss the practicalities and challenges of managing exit-anaesthesia.
Advances in prenatal early diagnosis of foetal congenital airway malformations identify those that will benefit from this intervention. This, together with the concurrent advancements of surgical techniques, has resulted in improved survival for babies with airway obstruction that would make spontaneous ventilation or placement of an endotracheal tube after delivery impossible [2].
In 1989, Norris and colleagues [3] first attempted to manage the airway of a foetus with a large cervical teratoma. The foeto-placental circulation could be maintained only for 10 minutes, after which the foetus’ condition deteriorated. It is unclear whether the infant was fully or partially delivered, but rigid bronchoscopy and tracheotomy were attempted without success and the infant died.
Since then, the indications for EXIT procedures have expanded to include a variety of foetal congenital abnormalities outlined in table-1.
Table-1: Outlines the Indications for EXIT procedure
How different is EXIT procedure from caesarean section
In older text books e.g. Wylie and Churchill Davidson, there are two terms mentioned in obstetric section: I-D interval (Incision to Delivery time) which should be approximately 3 minutes; and U-D interval (Uterine incision to Delivery time) of 30-60 seconds.This was to minimise foetal exposure to anaesthetic agents. Moreove