Description

The aim of the study is to investigate the safety and feasibility of chronic maternal hyperoxygenation in pregnancies affected by fetal congenital heart disease, specifically those pregnancies in which the fetus has single ventricle physiology with aortic arch obstruction. The treatment has a potentially neuroprotective effect on the fetus. This would be desirable as the neurodevelopmental outcomes of the survivors of this form of congenital heart disease are significantly below normal. However, transplacental oxygen has not been tried in this setting, and so before embarking on a trial, the investigators need to establish that the treatment is safe and feasible. This will be accomplished by recruiting subjects which meet the eligibility criteria and commence treatment at the time of diagnosis, usually in the second trimester, and by comparing outcomes with a historical cohort with CHD diagnoses with no oxygen intervention. The oxygen will be delivered to the mother via nasal prongs continuously at a rate of up to 4 L/min. Oxygen concentrators will be supplied to the subjects' homes, and a range of portable devices will also be provided to allow them to continue with usual activities of daily living. A series of follow up appointments will be arranged to check the status of the mother and fetus. Mothers will be invited to keep a diary of their adherence to the treatment. A range of routine clinical and research data on the condition of the fetus and newborn will be collected.