Assessment of extremely premature lambs supported by the Extrauterine Environment for Neonatal Development (EXTEND).

BACKGROUND: Our team has previously reported physiologic support by the EXTra-uterine Environment for Neonatal Development (EXTEND) of 105 to 117 days gestational age (GA) lambs for up to 28 days with normal organ maturation. However, the fetal lamb brain matures more rapidly, requiring the study of 90-105 day GA fetal lambs to assess more neurodevelopmentally equivalent lambs to the 23-25 week GA extreme premature infant. METHODS: Extremely preterm lambs (90-95 days of GA) were delivered by C-section and supported by EXTEND. Estimated circuit flows were maintained at around 325 ml/kg/min. After support on EXTEND, MRI and histopathologic analysis were performed and compared to 105-112 days GA control lambs. RESULTS: The extremely preterm group includes 10 animals with a mean GA of 91.6 days, a mean weight at cannulation of 0.98 kg and a mean length of stay on EXTEND of 13.5 days (10-21 days). Hemodynamics and oxygenation showed stable parameters. Animals showed growth and physiologic cardiac function. MRI volumetric and diffusion analysis was comparable to controls. Histologic brain analysis revealed no difference between study groups. CONCLUSION: EXTEND appears to support brain and cardiac development in an earlier gestation, less mature, lamb model. IMPACT: Prolonged (up to 21 days) physiological support of extremely preterm lambs of closer neurodevelopmental equivalence to the 24-28 gestational week human was achieved using the EXTEND system. EXTEND treatment supported brain growth and development in extremely preterm fetal lambs and was not associated with intraventricular hemorrhage or white matter injury. Daily echocardiography demonstrated physiologic heart function, absence of cardiac afterload, and normal developmental increase in cardiac chamber dimensions. This study demonstrates hemodynamic and metabolic support by the EXTEND system in the extremely preterm ovine model.

Preschool neurological assessment in congenital diaphragmatic hernia survivors: outcome and perinatal factors associated with neurodevelopmental impairment.

OBJECTIVE: To evaluate the preschool neurodevelopmental outcome in CDH survivors between 2 and 5 years of age and to identify perinatal and postnatal factors that may be predictive of persistent neurological deficits. METHODS: The study cohort consists of 60 CDH survivors that were enrolled in our prospective, follow-up program between January 2006 and September 2012. Developmental assessment of study participants between 2 and 3 years of age was performed using the Bayley Scales of Infant Development, 3rd Edition (BSID-III). Cognitive outcomes of CDH children older than 3 years of age were evaluated using The Wechsler Preschool and Primary Scale of Intelligence, 3rd Edition (WPPSI-III). Neurodevelopmental delay was defined by a score of ≤ 85 in any of the evaluated composite scores. Severe impairments were defined as a score of ≤ 69 in at least one domain tested. RESULTS: Mean follow-up for children assessed by BSID-III (n=42) and WPPSI-III (n=18) was 28 ± 4.5 months and 58 ± 4.0 months, respectively. As a group, mean composite and subdomain BSID-III and WPPSI-III scores were within the expected normal range. For the BSID-III group, 9 (22%) had mild deficits in at least one domain, and 6 (14%) had severe deficits in at least one. Only 3 (7%) patients demonstrated severe neurological delays for all BSID-III composite scales. For the WPPSI-III group, 4 (22%) patients scored within the borderline-delayed range for at least one subscale and only one (6%) child had a WPPSI-III VIQ score in the severe delay range. Abnormal muscle tonicity was found in 35% (hypotonicity 33%, hypertonicity 2%). Need for ECMO, prolonged ventilation, hypotonicity, and other surrogate markers of disease severity (P<0.05) were associated with borderline or delayed neurological outcome. CONCLUSION: The majority of CDH children are functioning in the average range at early preschool and preschool age. Neuromuscular hypotonicity is common in CDH survivors. CDH severity appears to be predictive of adverse neurodevelopmental outcome.

Right congenital diaphragmatic hernia: Prenatal assessment and outcome.

PURPOSE: To understand the natural history of right congenital diaphragmatic hernia (CDH), the authors retrospectively reviewed 27 cases of right CDH that presented for prenatal evaluation or postnatal treatment. METHODS: Between 1995 and September 2002, a total of 194 cases of fetal CDH were evaluated and included 22 right-sided defects. The authors reviewed prenatal diagnostic studies (ultrasound scan, magnetic resonance imaging [MRI] echocardiography) and pre- and postnatal outcomes in these 22 cases of right CDH. Five additional cases of right CDH without a prenatal diagnosis were reviewed. RESULTS: The mean gestational age at evaluation was 26.1 weeks. The lung area to head circumference ratio (LHR) ranged from 0.32 to 2.5. In all cases, the fetal liver was herniated into the right chest. Associated anomalies were common. There were no karyotype abnormalities (17 of 22 tested). There were 4 terminations. Nine of the 18 (50%) continuing pregnancies had polyhydramnios, premature rupture of membranes, or preterm labor. The mean gestational age at birth was 36.8 weeks. One patient underwent tracheal occlusion at 27 weeks, and 2 patients died before postnatal repair. Overall survival rate (22 prenatal plus 5 postnatal diagnoses) was 19 of 27 (70%). Postnatal survival rate was 19 of 23 (83%). A Gore-tex (W. L. Gore and Associates, Flagstaff, AZ) patch was utilized in 14 of 21 neonates undergoing surgery. Twelve of 23 (52%) required extracorporeal membrane oxygenation (ECMO) with a 75% survival rate. Significant morbidity occurred in 10 of 19 survivors and included neurologic sequelae in 6 of 19 (32%). CONCLUSIONS: MRI was helpful in the determination of liver position and confirmation of diagnosis. The high incidence of preterm complications, frequent need for ECMO, and high prevalence of comorbidities are indicative of the severity of this CDH population and warrant close prenatal surveillance and delivery at a tertiary care center with ECMO capability.

Sacrococcygeal teratoma: prenatal assessment, fetal intervention, and outcome.

PURPOSE: To understand the natural history and define indications for fetal intervention in sacrococcygeal teratoma (SCT), the authors reviewed all cases of fetal SCT presenting for evaluation. METHODS: Prenatal diagnostic studies including ultrasound scan, magnetic resonance imaging (MRI), echocardiography and pre- and postnatal outcomes were reviewed in 30 cases of SCT that presented between September 1995 and January 2003. RESULTS: The mean gestational age (GA) at presentation was 23.9 weeks (range, 19 to 38.5) with 3 sets of twins (10%). Overall outcomes included 4 terminations, 5 fetal demises, 7 neonatal deaths, and 14 survivors. Significant obstetric complications occurred in 81% of the 26 continuing pregnancies: polyhydramnios (n = 7), oligohydramnios (n = 4), preterm labor (n = 13), preeclampsia (n = 4), gestational diabetes (n = 1), HELLP syndrome (n = 1), and hyperemesis (n = 1). Fetal intervention included cyst aspiration (n = 6), amnioreduction (n = 3), amnioinfusion (n = 1), and open fetal surgical resection (n = 4). Indications for cyst aspiration and amnioreduction were maternal discomfort, preterm labor, and prevention of tumor rupture at delivery. Although 15 SCTs were solid causing risk for cardiac failure, only 4 fetuses met criteria for fetal debulking based on ultrasonographic and echocardiographic evidence of impending high output failure and favorable anatomy at 21, 23.6, 25, and 26 weeks' gestation. Intraoperative events included maternal blood transfusion (n = 1), fetal blood transfusion (n = 2), chorioamniotic membrane separation (n = 2), and fetal arrest requiring successful cardiopulmonary resuscitation (CPR) (n = 1). In the fetal resection group, 3 of 4 survived with mean GA at delivery of 29 weeks (range, 27.6 to 31.7 weeks), mean birth weight of 1.3 kg, hospital stay ranging from 16 to 34 weeks, and follow-up ranging from 20 months to 6 years. Postnatal complications in the fetal surgery group included neonatal death (n = 1, secondary to premature closure of ductus arteriosus with cardiac failure), embolic event (n = 1, resulting in unilateral renal agenesis, jejunal atresia), chronic lung disease (n = 1), and tumor recurrence (n = 1). CONCLUSIONS: For fetal SCT, the rapidity at which cardiac compromise can develop and the high incidence of obstetric complications warrant close prenatal surveillance. Amnioreduction, cyst aspiration, and surgical debulking are potentially life-saving interventions.