ABSTRACT
Introduction: The EXIT (ex-utero intrapartum treatment) procedure allows management of an abnormal fetal airway during operative delivery while they remain on utero-placental circulation. The vast majority of published cases were conducted under deep volatile anaesthesia [1] in order to provide uterine relaxation and a degree of fetal anaesthesia.10 cases have been reported under combined spinalepidural anaesthesia or intrathecal catheter, with supplemental GTN (glyceryl trinitrate) and remifentanil infusions. Recent research has improved the ability to predict the likelihood and complexity of surgical intervention. Regional anaesthesia cases all had a hysterotomy time of under 21 minutes. Here we present the first case report of an EXIT procedure conducted with simple spinal anaesthesia. Case Report: A 35-year-old woman with a BMI of 37 kg/m2, asthma and a recent COVID-19 pneumonia, had a history of post-dural puncture headache after a difficult epidural for labour, spinal anaesthetics requiring ultrasound and a lumbar puncture requiring x-ray guidance. Her fetal MRI had shown a 5.6 cm cystic neck mass, with a deviated but patent airway. The ENT team predicted surgical interventionwas unlikely or would be very short, but intubation likely. We advised a general anaesthetic as our centre did not yet have experience with EXIT under regional anaesthesia, but the patient adamantly wanted spinal anaesthesia until the baby was born, to be aware of their outcome on delivery. She preferred to avoid an epidural. An arterial line aided the challenging blood pressure management with intrathecal hyperbaric bupivacaine 13.5 mg and diamorphine 300 μg, remifentanil and GTN infusions. The uterus remained relaxed on 2.3 μg/kg/minute of GTN. Uterine tonewas later re-established with intravenous Syntocinon 10 U and intramuscular ergometrine 500 μg, with only 500 mL maternal blood loss. Despite remifentanil target controlled infusion (Minto model) at 3.5 ng/mL for 15 minutes before hysterotomy, the baby cried spontaneously. Hysterotomy timewas two minutes. Discussion: Our team were satisfied with this technique, allowing us to offer more choice to mothers with an expected short EXIT procedure. The utero-placental transfer of remifentanil has previously been found to be variable, but cases have described no fetal response to intubation from maternal remifentanil titrated to light sedation [2]. It is common for additional drugs to be given directly to the fetus even with volatile anaesthetic.