Original article SWISS MED WKLY 2007;137:279–285 · www.smw.ch 279 Peer reviewed article Ex utero intrapartum treatment (EXIT), a resuscitation option for intra-thoracic foetal pathologies Christian Kerna, Michel Ange, Moralesb, Barbara Peiryc, Riccardo E. Pfisterc a Anaesthesia, University Hospital Geneva, Switzerland b Gynaecology and Obstetrics, University Hospital Geneva, Switzerland c Paediatrics, University Hospital Geneva, Switzerland Summary The ex utero intrapartum treatment (EXIT) requires a caesarean section that specifically differs procedure is designed to guarantee sufficient oxy- from the traditional caesarean section during genation for a foetus at risk of airway obstruction. which uterine tone is maintained to minimize ma- This is achieved by improving lung ventilation, ternal bleeding. To guarantee foetal oxygenation usually by establishing an airway during caesarean during the EXIT procedure, profound uterine delivery whilst preserving the foetal-placental cir- relaxation is desired. To gain time with optimal culation temporarily. Indications for the EXIT placental oxygenation in order to safely perform an procedure have extended from its original use in airway intervention in a baby at risk of hypoxia may reversing iatrogenic tracheal obstruction in con- require deep inhalation anaesthesia and/or to- genital diaphragmatic hernia to naturally occur- colytic agents. We review the EXIT procedure and ring upper airway obstructions. We report our present a case series from the University Hospital experience with a new and rarely mentioned indi- of Geneva that contrasts with the common indica- cation for the EXIT procedure, intra-thoracic tion for the EXIT procedure usually based on volume expansions. The elaboration of lowest risk upper airway obstruction by its exclusive indica- scenarios through balancing risks with alternative tion for intra-thoracic malformations/diseases. options, foetal or neonatal intervention and coor- dination between professionals from various disci- Key words: EXIT procedure; foetal intra-thoracic plines are the most important conditions for a pathologies; resuscitation successful EXIT procedure. The EXIT procedure Introduction Modern technologies, including ultrasonogra- ital diaphragmatic hernia [1, 2]. Over time, its use phy and magnetic resonance imaging (MRI), have has expanded to include management of a variety improved prenatal diagnosis of anatomic malfor- of situations, including all kinds of extrinsic (ter- mations. Early diagnosis is the condition for foetal atoma, lymphangioma) [3] or intrinsic (laryngeal or perinatal interventions and planning of targeted atresia, congenital upper airway obstruction) [4] resuscitation procedures. Techniques to control obstructive malformations of the upper airways uterine tone were developed specifically for foetal and more recently intra-thoracic lesions [5] such surgery allowing prolonged and complicated in- as congenital hydrothorax and pleural effusions terventions. In principle, the ex utero intrapartum [6]. Various interventions have been performed treatment (EXIT) procedure is designed to estab- with EXIT support including intra-tracheal intu- lish adequate ventilation and oxygenation by bation, bronchoscopy, surfactant instillation, tra- securing the airway during delivery, mainly a cae- cheotomy, tracheoplasty and, more rarely, ablative sarean section, in a foetus at risk of delayed respi- surgery of compressive tumours [1, 2, 5, 7–11]. ratory adaptation, whilst temporarily preserving Effective neonatal resuscitation aims to secure the foetal-placental circulation. The EXIT proce- sufficient tissue oxygenation at all times between dure was initially developed as a means of re-estab- intra-uterine foetal life and neonatal life, whether No financial support declared. lishing an airway after iatrogenic occlusion of the breathing becomes completely autonomous or foetal trachea to promote lung growth in congen- requires ventilator support. The EXIT procedure Ex utero intrapartum treatment 280 provides a means to maintain oxygenation in increased by a short invasive procedure able to neonates with short-lived respiratory insufficiency improve spontaneous or mechanical ventilation. or any condition that may significantly improve The EXIT procedure commonly requires a following a short medical intervention. A number caesarean section (CS) that specifically differs from of case reports and some case series originating the traditional CS. In contrast to the routine CS mainly from two American centres [1, 5, 10, 12, 13] where uterine tone is maintained to minimize report on the management of iatrogenic tracheal maternal bleeding and where uterine atony is occlusion and some expanded indications for nat- dreaded, for the EXIT procedure, profound uter- urally occurring upper airway obstructions. Re- ine relaxation using deep anaesthetic inhalation ports on intra-thoracic indications for the EXIT agents is desired, thus increasing maternal risks. In procedure remain exceptional [5, 6, 9, 10]. Besides some cases, tocolytic drugs may further be neces- reviewing general aspects of the EXIT procedure, sary. In addition, a dedicated team skilled in com- the current report focuses on intra-thoracic and plex neonatal resuscitation during maternal oxy- lung pathologies that compress the normal lung in genation of the partially or completely delivered which intra-thoracic volume can be significantly foetus is essential. Case series We report our experience in a small case series of but these interventions remained ineffective in producing EXIT procedures with unusual indications managed at lasting release of compression in several large cysts and our hospital between 2000 and 2005 for intra-thoracic ex- hydrothorax. pansion reducing the volume of the ‘normal’ underlying In contrast to the classical EXIT procedure mainly lung tissue, thus putting the newborn at very high risk for used to manage and secure obstructed upper airways, the postnatal hypoxia. Even an optimized and targeted neona- procedure was adapted for pathologies affecting lung tal resuscitation with immediate postnatal thoracocente- volume. The aim was to increase intra-thoracic space for sis was expected to lead to cardiopulmonary compromise ventilation of the remaining functional lung tissue by with a high likelihood of several minutes of asphyxia. aspiration of the liquid components of the pathologic ex- In all five cases, an important polyhydramnios led to pansion and to establish an airway for postnatal support. the diagnosis of the foetal pathology between 14 and 38 We aimed for a short and minimally invasive procedure to weeks gestation (figure 1). A pathologic volume expansion avoid lengthy interventions with increasing maternal occupied more than half the intra-thoracic space leading morbidity [9]. to a deviation of the mediastinum in all cases. Although The interventions were planned with a multidiscipli- still rare in occurrence, such intra-thoracic pathologies are nary team after decision on the lowest risk scenario. Spe- now more common than upper airway obstructions. The cial attention was paid to supplying detailed information general characteristics of the five cases are reported in to the parents, particularly as severe lung hypoplasia was table 2. Two foetuses had a beginning hydrops, a condi- impossible to exclude in all our cases with large intra- tion known to considerably worsen the prognosis [14–17]. thoracic expansion pathologies. An ultrasound control was None of the pathologies was easily accessible for surgery performed shortly before, and in some cases during the in utero because of foetal and/or placental position such EXIT procedure, in order to localise and map the placenta that thoracocentesis was considered impossible without before hysterotomy as well as estimating foetal umbilical harm, or at least high risk, to vital organs of the mother or cord length (to plan positioning of the newborn after de- foetus. Insertion of a pigtail catheter for drainage and mul- livery) and anticipate the ideal anatomical puncture site for tiple punctures were attempted in one foetus (CN) with thoracocentesis or drainage. congenital cystic adenomatoid lung malformation (CCAM), The first three CS were performed in the obstetric Figure 1 Foetal magnetic reso- nance imaging – T2 weighted A Longitu- dinal section of the amniotic cavity and foetus. Note the con- siderable amount of amniotic fluid and the compressed lung surrounded by a hy- drothorax. B Trans- verse section of the foetal thorax in abun- dant amniotic fluid. The foetal lung is outlined for volume determination. SWISS MED WKLY 2007;137:279–285 · www.smw.ch 281 Figure 2 was hastened after 4 minutes due to fading umbilical Example of EXIT pro- pulses. All babies, except LV, rapidly developed motor ac- cedure with position- tivity and breathing efforts despite sedation and analgesia ing of the baby at to the mother (table 3). Umbilical cord pH after clamping right angle to the mother on padded and early neonatal adaptation was good in all five cases sterile surface. Note (table 4). that the umbilical A short EXIT procedure time of 4 to 9 minutes was cord length just al- required to insert drainage and aspirate hydrothorax or lows this position. Whilst the obstetri- cystic fluid or, in one case, ascites. Establishment of an air- cian is sensing cord way was performed during placental circulation in two pulsatility, the new- cases, as the neonates started breathing spontaneously born resuscitation after withdrawal