///2009 Abstract Details
2009 Abstract Details2019-08-03T15:55:31-06:00

Ex Utero Intrapartum Treatment (EXIT) Procedure for Management of Congenital High Airway Obstruction Syndrome (CHAOS) in a Vertex/Breech Twin Gestation

Abstract Number: 229
Abstract Type: Case Report/Case Series

Gillian Newman MD, PhD1 ; Cristianna Vallera MD2; Michael Lee MD3; Richard Elliott MD4; Eugenie S. Heitmiller MD5

Introduction: The EXIT procedure, which maintains uteroplacental gas exchange while securing the fetal airway, is now used for increasingly complex presentations which could otherwise be fatal due to the inability to oxygenate the infant after birth (1, 2).

Case Presentation: A 44-year-old, G4, P0120 woman with twin pregnancy presented with CHAOS in Twin B. A multidisciplinary planning session was held; the plan included intraoperative sonogram and intra-abdominal/extrauterine version of Twin B, who was in the superior, anterior breech position, to allow for the delivery of Twin A first.

An EXIT procedure was agreed upon at 36 1/7 weeks gestation. Two days prior to the procedure, a walk-through was held in the OR. On the day of the case, plan, positioning, equipment, drug supplies and blood availability were verified. The patient was pretreated with sodium citrate, placed in left uterine displacement & pre-oxygenated with standard & fetal monitors. Rapid sequence induction was performed. A 2nd peripheral IV and radial arterial line were placed. Nitroglycerin infusion was titrated to uterine relaxation, and phenylephrine infusion was titrated to maintain maternal blood pressure. Incision was made 26 minutes after induction. Intra-abdominal/extrauterine version of Twin B was performed. Twin A was delivered without difficulty.

Twin Bs head, neck and right upper extremity were exteriorized. Warm normal saline was infused to maintain intrauterine volume. Pediatric anesthesiology administered IM fentanyl, atropine, and rocuronium, and placed a pulse oximetry probe. The otolaryngology team performed rigid bronchoscopy and tracheotomy. The obstetricians then completed delivery of Twin B; interdelivery interval was 20 minutes.

During the EXIT procedure, Twin Bs heart rate was 140-160 beats/min and oxygen saturation was 40-50%. The placenta did not separate from the uterus; uterine contractions were not present. One hour following surgery start time, the EXIT procedure was complete and the twins were stable in the NICU. The mother was stable throughout the procedure. Once Twin B was fully delivered, nitroglycerin, phenylephrine and desflurane were discontinued. Pitocin infusion was started and midazolam 5mg was given to the patient. During closure, the patient received propofol, hydromorphone, and ondansetron. Following 87 minutes of deep general anesthesia, uterine tone and hemostasis were excellent. After smooth emergence & extubation, the patients postoperative course was uneventful.

Discussion: During the EXIT procedure, it is imperative to maintain full uterine relaxation to prevent placental separation and subsequent loss of uteroplacental gas exchange, without compromising maternal cardiac output (1). A breech/vertex twin gestation, with unfavorable lie of the healthy twin, introduces risk to the healthy twin and increased organizational complexity. A multidisciplinary approach is crucial for a successful outcome.

SOAP 2009