Prenatal ABO/RHD Genotyping: A New Paradigm to Allow for Fresh Whole Blood for Cardiopulmonary Bypass in the Immediate Newborn Period.

Compared to standard component therapy, fresh whole blood (FWB) offers potential benefits to neonates undergoing cardiopulmonary bypass (CPB) in the context of open cardiac surgery: decreased blood loss and subsequent risk of volume overload, improved coagulation status, higher platelet counts during and following CPB, circumvention of limited vascular access, and significantly reduced donor exposures. Obtaining FWB, however, entails 2-5 days of preparation, which often precludes its availability for neonates requiring CPB in the immediate newborn period. Using a multidisciplinary approach and molecular ABO/RHD genotyping on amniotic fluid, we developed a protocol to allow procurement of FWB for timed delivery followed by open cardiac surgery. Eligible subjects include patients undergoing genetic amniocentesis following the diagnosis of a fetal cardiac anomaly likely to require open surgical repair in the initial days after birth. This protocol has been successfully implemented following prenatal diagnosis of severe fetal cardiac anomalies. Taking advantage of the prenatal time period and the ability to perform fetal blood typing prenatally using molecular genotyping makes possible a new paradigm for the availability of FWB for CPB to improve perioperative, short-term, and long-term outcomes in a population comprised of some of the smallest and sickest patients who will undergo CPB.

Extracorporeal fetal support: a new animal model with preservation of the placenta.

BACKGROUND: Previous models of support for premature sheep fetuses have consisted of cesarean delivery followed by catheterization of umbilical or central vessels and support with extracorporeal membrane oxygenation (ECMO). The limitations of these models have been insufficient blood flow, significant fetal edema, and hemorrhage related to anticoagulation. METHODS: We performed a gravid hysterectomy on 13 ewes between 135 and 145days gestational age. The uterine vessels were cannulated bilaterally and circulatory support was provided via ECMO. Successful transition was defined as maintenance of fetal heart rate for 30minutes after establishing full extracorporeal support. Circuit flow was titrated to maintain mixed venous oxygen saturation (SvO2) of 70-75%. RESULTS: Seven experiments were successfully transitioned to ECMO, with an average survival time of 2hours 9minutes. The longest recorded time from cannulation to death was 6hours 14minutes. By delivering a circuit flow of up to 2120ml/min, all but one of the transitioned uteri were maintained within the desired SvO2 range. CONCLUSION: We report a novel animal model of fetal ECMO support that preserves the placenta, mitigates the effects of heparin, and allows for increased circuit flow compared to prior techniques. This approach may provide insight into a technique for future studies of fetal physiology.

Ex utero intrapartum treatment procedure for management of congenital high airway obstruction syndrome in a vertex/breech twin gestation.

Congenital high airway obstruction syndrome (CHAOS) is one indication for the ex utero intrapartum treatment (EXIT), which is used to secure the fetal airway, while fetal oxygenation is maintained by uteroplacental circulation. We report a successful EXIT procedure in a twin gestation in which one child had CHAOS while the other was a healthy child without any congenital abnormalities. After version of Twin B to allow for delivery of Twin A, Twin B underwent airway evaluation and tracheostomy for laryngeal atresia prior to delivery.

Isolated prenatal choroid plexus cysts do not affect child development.

OBJECTIVE: To examine the effect of isolated prenatal choroid plexus cysts (CPCs) on child cognitive, behavioral, motor, and autonomic development at 18 months of age. METHODS: A prospective design was implemented to identify CPC cases and controls in mid-pregnancy. Cases (n = 25) and controls (n = 45) participated in a follow-up visit when children were 18 months of age. Child mental and motor development was assessed using standard developmental assessments, socioemotional and behavioral functioning during testing was rated by examiners, and accelerometers provided measures of motor activity and energy expenditure. Cardiac patterns were collected using a three-lead electrocardiogram (ECG) and quantified as indicators of autonomic control of the heart, including vagal tone. RESULTS: No significant differences were found in any outcome measure between children with prenatal CPC detection and those without. CONCLUSION: Findings should provide reassurance to practitioners and parents that isolated CPCs in fetuses with normal karyotypes do not affect child development after birth.