Machine Learning to Predict Outcomes of Fetal Cardiac Disease: A Pilot Study.

Prediction of outcomes following a prenatal diagnosis of congenital heart disease (CHD) is challenging. Machine learning (ML) algorithms may be used to reduce clinical uncertainty and improve prognostic accuracy. We performed a pilot study to train ML algorithms to predict postnatal outcomes based on clinical data. Specific objectives were to predict (1) in utero or neonatal death, (2) high-acuity neonatal care and (3) favorable outcomes. We included all fetuses with cardiac disease at Sunnybrook Health Sciences Centre, Toronto, Canada, from 2012 to 2021. Prediction models were created using the XgBoost algorithm (tree-based) with fivefold cross-validation. Among 211 cases of fetal cardiac disease, 61 were excluded (39 terminations, 21 lost to follow-up, 1 isolated arrhythmia), leaving a cohort of 150 fetuses. Fifteen (10%) demised (10 neonates) and 65 (48%) of live births required high acuity neonatal care. Of those with clinical follow-up, 60/87 (69%) had a favorable outcome. Prediction models for fetal or neonatal death, high acuity neonatal care and favorable outcome had AUCs of 0.76, 0.84 and 0.73, respectively. The most important predictors for death were the presence of non-cardiac abnormalities combined with more severe CHD. High acuity of postnatal care was predicted by anti Ro antibody and more severe CHD. Favorable outcome was most predicted by no right heart disease combined with genetic abnormalities, and maternal medications. Prediction models using ML provide good discrimination of key prenatal and postnatal outcomes among fetuses with congenital heart disease.

Enhanced recovery after fetal spina bifida surgery: what is our global practice?

OBJECTIVE: Prenatal spina bifida closure results in improved outcomes for the child compared to postnatal surgery but is associated with significant maternal morbidity. Optimization of the perioperative care for women who underwent fetal spina bifida surgery could improve maternal and pregnancy outcomes. Enhanced Recovery After Surgery (ERAS) protocols are multimodal, evidence-based care plans that have been adopted for multiple surgical procedures to promote faster and better patient recovery and shorter hospitalization. This study aims to explore if fetal centers have implemented ERAS principles in this setting. Furthermore, we provide recommendations for the perioperative management of patients undergoing fetal spina bifida surgery. METHODS: Fifty-three fetal therapy centers offering prenatal surgery for open spina bifida were identified and invited to complete a digital questionnaire covering their pre-, intra- and postoperative management. An overall score was calculated per center based on the center's compliance with 20 key ERAS principles, extrapolated from ERAS guidelines for cesarean section, gynecologic oncology and colorectal surgery. Each item was scored 1 or 0 when the center did or did not comply with each principle, with a maximum score of 20. RESULTS: The questionnaire was completed by 46 centers in 17 countries (response rate 87%). Twenty-two centers (48%) exclusively perform open fetal surgery (laparotomy and hysterotomy), whereas 14 (30%) offer both open and fetoscopic procedures and 10 (22%) use fetoscopy only. The perioperative management of patients undergoing fetoscopic and open surgery was highly similar. The median ERAS score was 12 (mean 12.5, SD 2.4, range 8-17). Center compliance was the highest for the use of regional anesthesia (98%), avoidance of bowel preparation (96%), and thromboprophylaxis (96%), while the lowest compliance was achieved for preoperative carbohydrate loading (15%), postoperative nausea and vomiting prevention (33%), avoidance of overnight fasting (33%) and a 2-hour fasting period for clear fluids (20%). ERAS scores were similar in centers with a short (2-5 days), medium (6-10 days) and long (≥11 days) hospital stay (12.8 ± 2.4, 12.1 ± 2.0, and 10.3 ± 3.2, respectively, p=0.15). Furthermore, there was no significant association between ERAS score and surgical technique or center volume. CONCLUSION: The perioperative management of fetal spina bifida surgery is highly variable across fetal therapy centers worldwide. Standardizing protocols according to ERAS principles may improve patient recovery, reduce maternal morbidity, and shorten hospital stay after fetal spina bifida surgery. This article is protected by copyright. All rights reserved.

Safety and feasibility pilot study of continuous low-dose maternal supplemental oxygen in fetal single ventricle heart disease.

OBJECTIVES: Fetuses with single ventricle physiology (SVP) exhibit reductions in fetal cerebral oxygenation with associated delays in fetal brain growth and neurodevelopmental outcomes. Maternal supplemental oxygen (MSO) has been proposed to improve fetal brain growth but current evidence on dosing, candidacy, and outcomes are limited. In this pilot study, we evaluated the safety and feasibility of continuous low-dose MSO in the setting of SVP. METHODS: This single-centre, open-label, pilot phase 1 safety and feasibility clinical trial included 25 pregnant individuals with a fetal diagnosis of SVP. Participants self-administered continuous supplemental oxygen using medical-grade oxygen concentrators for up to 24 hours per day from the second half of gestation until delivery. The primary aim was the evaluation of the safety profile and feasibility of MSO. A secondary preliminary analysis was performed to assess the impact of MSO on the fetal circulation by echocardiography and late-gestational cardiovascular magnetic resonance, early outcomes including brain growth and pre-operative brain injury, and 18-month neurodevelopmental outcomes by the Bayley Scales of Infant and Toddler Development 3rd Edition compared to a contemporary fetal SVP cohort that received standard of care (SOC). RESULTS: Among 25 participants, the average maternal age at conception was 35 years, and fetal SVP diagnoses included 16 right ventricle dominant, 8 left ventricle dominant, and 1 indeterminant ventricular morphology. Participants started the trial at approximately 29.3 gestational weeks and took MSO for a median 16.1 hours per day for 63 days, cumulating a median 1029 hours of oxygen intake from enrollment until delivery. The only treatment-associated adverse events were nasal complications that were typically resolved by attaching a humidifier unit to the oxygen concentrator. No premature closure of the ductus arteriosus or unexpected fetal demise was observed. In the secondary analysis, MSO was not associated with any changes in fetal growth, middle cerebral artery pulsatility index, cerebroplacental ratio, nor head circumference to abdominal circumference ratio Z-scores over gestation compared to SOC. Although MSO was associated with changes in umbilical artery pulsatility index Z-score over gestation compared to SOC (p=0.02), this was likely due to initial baseline differences in placental resistance. At late-gestational cardiovascular magnetic resonance, MSO was not associated with any significant increase in umbilical vein oxygen saturation, fetal oxygen delivery, or fetal cerebral oxygen delivery. Similarly, we observed no differences in newborn outcomes including brain volume and pre-operative brain injury, nor mortality by 18 months of age, nor neurodevelopmental outcomes at 18 months of age. CONCLUSIONS: This pilot phase 1 clinical trial indicates low-dose maternal supplemental oxygen therapy is safe and well tolerated in pregnancies diagnosed with fetal SVP. However, our protocol was not associated with any significant changes in fetal circulatory physiology or improvements in early neurologic or neurodevelopmental outcomes. This article is protected by copyright. All rights reserved.