Anaesthetic management of obstetric patients with Chiari 1 malformation with or without syringomyelia: a multidisciplinary consensus statement from the Obstetric Anaesthetists' Association (OAA).

Anaesthetists working regularly on labour ward are likely to encounter obstetric patients with Chiari malformation with or without syringomyelia. The management of such patients has been variable in different institutions and advice on the safety of neuraxial procedures inconsistent. The most likely reason for management variations stems in the lack of any robust evidence in the literature and guidance based on individual perception of acceptable risk. The Obstetric Anaesthetists' Association (OAA) set up a multidisciplinary expert group of clinicians routinely involved in the management of obstetric patients with Chiari malformation and syringomyelia. The aim of the expert group was to conduct a literature review and critically evaluate the published evidence with the goal to reach a consensus on the appropriate management of obstetric patients with Chiari 1 malformation with or without syringomyelia receiving obstetric anaesthesia care. Recommendations and statements were graded as per the US Preventive Services Task Force methodology. A total of 1187 articles were identified in the initial literature search of which 49 were screened as relevant and used in the consensus statement document. A structured narrative review was undertaken which included antenatal care, mode of delivery, labour analgesia, anaesthesia for caesarean delivery and management of complications related to neuraxial techniques. The expert group agreed on eight recommendations and 10 statements which were assigned low or moderate level of certainty. We found almost no published evidence on the peripartum anaesthetic management of obstetric patients who experience significant or rare symptoms of Chiari malformation. Consequently, the expert group made recommendations and statements only considering patients who are on the less severe spectrum of symptoms of Chiari malformation and syringomyelia. With careful assessment and follow up most patients with stable or no symptoms can be managed within routine obstetric anaesthetic protocols.