Maternal and neonatal outcome of 100 consecutive triplet pregnancies.

The objective of this study is to determine the maternal and neonatal outcome of a large group of triplet gestations. A retrospective review of 100 triplet gestations managed and delivered between January 1992 and September 1999 by a single perinatal group is examined. These pregnancies were managed on an outpatient basis. Prophylactic interventions were not utilized. Ninety-six percent of the pregnancies had at least one complication, with preterm labor the most common. The median gestational age at delivery was 33 weeks (range 20.4 to 37, SD 4.1 weeks) with 14% of pregnancies delivering prior to 28 weeks' gestation. The corrected perinatal mortality rate was 97/1000. Minimal long-term morbidity was seen with delivery after 27 weeks' gestation. Pregnancy outcome did not vary with birth order or mode of conception. Triplet pregnancy is associated with a high rate ofantenatal complications. Favorable neonatal outcome can be obtained without the use of prophylactic interventions.

Congenital heart disease: the impact of delivery in a tertiary care center on SNAP scores (scores for neonatal acute physiology).

OBJECTIVE: It has been hypothesized that delivery in a tertiary care center might improve the clinical condition and outcome of infants born with congenital heart disease. The purpose of this study was to determine the effect of delivery in a tertiary care center on SNAP scores (scores for neonatal acute physiology) of infants admitted to the neonatal intensive care unit with major structural cardiac defects. STUDY DESIGN: This retrospective cohort study included 195 infants with major congenital heart disease admitted to the neonatal intensive care unit at the New England Medical Center between July 1, 1992, and June 30, 1998. SNAP scores were abstracted from the medical record. The values of 97 neonates with major cardiac defects born at the New England Medical Center were compared with those of 98 neonates transferred to our center after delivery in a community setting. A 2-tailed Student t test for independent samples was used to compare the mean SNAP scores between the 2 cohorts. RESULTS: The SNAP scores for infants with major cardiac defects who were born at the New England Medical Center ranged from 0 to 41, with a mean of 10.6 +/- 8.8. The values for infants with congenital heart disease who were transferred to our center after birth in community-based hospitals ranged from 0 to 34, with a mean of 11.1 +/- 7.0. There was no significant difference between the 2 populations (P =.646). A comparison of the mean SNAP scores of infants with prenatally diagnosed disease who were delivered at our center versus infants with postnatally diagnosed disease who were delivered in community hospitals was also statistically not significant (P =.824). CONCLUSION: Delivery in a tertiary care center does not improve SNAP scores of infants with major structural cardiac defects.

Neonatal morbidity and mortality associated with triplet pregnancy.

OBJECTIVE: To compare neonatal morbidity and mortality in a large cohort of triplet pregnancies with singleton and twin neonates managed at a single tertiary center over a short time. METHODS: Records from all triplet pregnancies managed and delivered from 1992 to 1996 were reviewed for neonatal outcome data. Pregnancies delivered before 20 weeks' gestation and neonates with lethal congenital anomalies were excluded. The comparison group comprised all singleton and twin neonates managed in the same neonatal intensive care unit (NICU) during the same period. RESULTS: During the 5-year period, 55 triplet pregnancies and their resulting 165 neonates were managed and delivered at this center. Their outcomes were compared with those of 959 singleton and 357 twin neonates born at similar gestational ages. The median gestational age at delivery for triplets was 32.1 weeks, and 149 of the 165 infants were admitted. Sixteen triplet neonates were not admitted to our neonatal intensive care unit, 12 because of previable gestational age, three because of stillbirth, and one because of a lethal congenital anomaly. The crude perinatal mortality rate in triplets was 121 per 1000 births, and there was no significant difference in outcome based on triplet birth order. There were no significant differences in survival rates between singleton, twin, and triplet neonates, with an overall neonatal survival of 95%, 95%, and 97%, respectively. The only significant differences in morbidity were an increased incidence of mild intraventricular hemorrhage (relative risk [RR] 6.20; 95% confidence interval [CI] 2.64, 14.61), mild retinopathy of prematurity (RR 20.05; 95% CI 3.59, 111.79), and severe retinopathy of prematurity (RR 46.69; 95% CI 6.25, 348.85) in triplets compared with singletons, and severe retinopathy of prematurity (RR 6.83; 95% CI 1.24, 37.56) in triplets compared with twins. CONCLUSION: When stratified by gestational age, triplet neonates delivered at 24-34 weeks' gestation have similar outcomes as singleton and twin neonates, with the only clinically significant difference being an increased incidence of retinopathy of prematurity in triplets.

Dietary L-arginine prevents fetal growth restriction in rats.

OBJECTIVE: Alterations in maternal plasma arginine concentration accompany normal pregnancy. Nitric oxide is synthesized from L-arginine and influences fetal growth. We hypothesized that L-arginine would influence fetal growth and hypoxia-induced uricemia in a maternal hypoxia-induced fetal growth restriction model. STUDY DESIGN: Fetal growth on day 21 of gestation was assessed in timed pregnant Wistar rats with or without exposure to maternal hypobaric hypoxia. Animals exposed to hypoxia received either no supplement or supplementation of drinking water with 0.2% L-arginine, 2% L-arginine, or 2% glycine. On day 21 of gestation, fetuses were delivered by hysterotomy and fetal and placental weights were obtained. Maternal and fetal plasma were assayed for uric acid as an index of tissue hypoxia. Xanthine oxidase and xanthine dehydrogenase, precursors of uric acid and reactive oxygen species, were assayed in maternal tissue. Results were analyzed by analysis of variance with correction for multiple comparisons. RESULTS: Exposure of rats on normal diets to hypoxia resulted in a 30% reduction in fetal weights. L-Arginine, 2% or 0.2%, prevented the reduction in fetal weight (p < 0.0001). Isocaloric and isonitrogenous supplementation with glycine did not influence hypoxia-induced fetal growth restriction. CONCLUSION: L-Arginine, but not glycine, ameliorates maternal hypoxia-induced fetal growth restriction in the rat.

Neonatal outcome of very premature infants from multiple and singleton gestations.

OBJECTIVES: Our purpose was to determine whether, in the era of surfactant treatment, very premature neonates from multiple gestations have outcomes similar to those of singletons. STUDY DESIGN: We collected data on 572 infants (369 singletons, 203 multiple gestation) born and cared for at a single institution from July 1, 1992, through Dec, 31, 1994, of gestational ages 24 to 32 weeks. We compared singleton infants with infants from multiple gestations within gestational age categories 24 to 26 weeks, 27 to 29 weeks, and 30 to 32 weeks. RESULTS: Infants of multiple gestations were more likely to have been born by cesarean section. The incidences of respiratory distress syndrome and bronchopulmonary dysplasia were similar, except that respiratory distress syndrome was more frequent in infants of multiple gestations at 30 to 32 weeks. Infants of multiple gestations from 27 to 29 weeks were more likely to have at least one of the following complications: patent ductus arteriosus, intraventricular hemorrhage, necrotizing enterocolitis, or retinopathy of prematurity. Further analysis suggested that this increase is unlikely to cause a difference in long-term outcome. The survival to discharge increased from 79% (multiples) and 81% (singletons) at 24 to 26 weeks to 98% (multiples) and 96% (singletons) at 30 to 32 weeks. CONCLUSIONS: Incidences of significant neonatal problems in very premature infants from multiple gestations who are born alive are little different from those of singletons. These data should have an impact on decision making in the perinatal and neonatal care of infants of multiple gestations.

A comparison of neonatal outcomes of age-matched, growth-restricted twins and growth-restricted singletons.

A retrospective cohort study was performed to determine whether growth-restricted fetuses of a twin gestation are at increased risk of adverse neonatal outcome compared with growth-restricted singletons. One cohort was comprised of 48 growth-discordant twin pregnancies in which the birth weight of the smaller twin was less than the tenth percentile. The neonatal outcomes of the 48 growth-restricted twin infants were compared with a cohort of 96 singleton infants matched by gestational age, degree of growth restriction, and gender. Outcomes evaluated included: length of stay, days of assisted ventilation, and diagnoses of morbidities of prematurity, congenital abnormalities, and neonatal death. No significant difference was detected in rates of neonatal morbidity or mortality. The overall neonatal death rate in the twins was 125 of 1000 and in the singletons was 104 of 1000 (Odds ratio 1.2, 95% confidence interval [CI]0.4-3.3). Growth-restricted twins have similar rates of adverse neonatal outcomes as compared with growth-restricted singletons. Both have high rates of morbidity and neonatal death. Twins and singletons should receive comparable diagnostic evaluation and antepartum management for growth restriction.

Ultrasound predictors of neonatal outcome in intrauterine growth restriction.

Our purpose was to assess the value of commonly performed ultrasound parameters in predicting neonatal outcome of fetuses with intrauterine growth restriction (IUGR). One hundred twenty-seven patients were identified on ultrasound examination to have IUGR. Estimated weight percentile, amniotic fluid volume, umbilical artery Doppler velocimetry, and head circumference/abdominal circumference ratio were compared with neonatal outcome. Thirty infants had severely adverse courses. The degree of growth restriction was strongly associated with adverse outcome and neonatal death. Umbilical artery Doppler waveforms with absent or reverse end-diastolic flow were predicted of neonatal death, bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC), and adverse outcome in general. Oligohydramnios was predictive of adverse outcome and neonatal death. Logistic regression also showed that absent or reverse end-diastolic flow and oligohydramnios were independent predictors of adverse outcome. Ultrasound findings of low estimated weight percentile, absent or reverse end-diastolic umbilical blood flow, and oligohydramnios are independent predictors of adverse neonatal outcome of growth restricted fetuses.

Elevated endothelin levels are associated with increased placental resistance.

OBJECTIVE: The purpose of this study was to measure cord blood endothelin-1,2 concentrations in growth-restricted infants with abnormal flow velocity waveforms. STUDY DESIGN: Endothelin-1,2 concentrations were measured by radioimmunoassay in the cord blood of 16 growth-restricted infants with abnormal flow velocity waveforms before delivery, 16 growth-restricted infants with normal flow velocity waveforms before delivery, and 44 appropriately grown infants. Clinical data regarding pregnancy complications and neonatal outcome were collected. RESULTS: The mean endothelin-1,2 concentration in growth-restricted infants with abnormal flow velocity waveforms (50.2 +/- 16.4 pg/ml) was significantly higher than in growth-restricted infants with normal flow velocity waveforms (33.3 +/- 14.2 pg/ml, p < 0.05) or in appropriately grown infants (25.8 +/- 9.7 pg/ml, p < 0.05). Oligohydramnios was also associated with elevated endothelin levels. CONCLUSION: We conclude that endothelin-1,2 concentrations are elevated in growth-restricted infants with abnormal flow velocity waveforms and may play a role in the development of abnormal fetoplacental resistance.

Early minimal feedings promote growth in critically ill premature infants.

Critically ill premature infants requiring mechanical ventilation and an umbilical artery catheter usually do not receive enteral feedings during the acute phase of their illness. We studied the safety and benefit of early minimal enteral feedings during this time in a prospective, controlled, and randomized study. Twenty-nine infants were randomly assigned to receive only standard intravenous fluid and nutrition (nothing per OS, NPO group; n = 13), or in addition to receive small-volume hypocaloric continuous feedings (1 ml/kg/h), beginning at 24 h of age (early-feeding group; n = 16). Standard enteral feedings were begun in both groups at the resolution of the acute phase of the illness and advanced by protocol. The two groups were of comparable birth weight, gestational age, and Apgar scores. There were no significant differences in the episodes of feeding intolerance. Two infants in the NPO group developed clinical signs of necrotizing enterocolitis. Serum diamine oxidase and somatomedin C were measured weekly until 30-60 days of age and were not different between the two groups. The early-feeding group required fewer days to reach 120 ml/kg/day enteral intake (early-feeding group 10 +/- 3 days, NPO group 13 +/- 4 days; p < 0.05). On day 30 of life the early-feeding group was 223 +/- 125 g above birth weight, while the NPO group was 95 +/- 161 g above birth weight (p < 0.05). The average intake (kcal/kg/day) from day 6 to day 30 was not different between the two groups. We conclude that early minimal feedings in critically ill very-low-birth-weight infants requiring mechanical ventilation are well tolerated and result in reduced time to reach 120 ml/kg/day of enteral feeding and in a greater weight gain by day 30 of life.

Pharmacologic approaches to the prevention and treatment of neonatal hyperbilirubinemia.

Because of the high frequency, serious sequelae, and complex and costly management, neonatal jaundice is a good candidate for preventive treatment. In this respect the clinical problem of neonatal jaundice has many similarities with the problem of hemorrhagic disease of the newborn. Both conditions are transient peculiarities of newborn metabolism. Most neonates exhibit the biochemical abnormality, but a small minority is placed in jeopardy of life or suffers serious sequelae. In both conditions a loose relationship exists between the degree of biochemical abnormality and the clinical manifestations that are poorly predicted by monitoring the abnormalities. The administration of vitamin K at birth corrected the biochemical abnormalities and eliminated clinical hemorrhagic disease. The simplicity, efficacy, and safety of vitamin K prevention of hemorrhagic disease of the newborn is the prototype in the search for the solution to the problem of neonatal jaundice. For most neonates, antenatal phenobarbital comes close to this prototype in terms of efficacy and simplicity. The combination of antenatal and postnatal therapy seems suitable for use in preterm labor in combination with tocolysis. This recommendation is conditional on the demonstration of safety by long-term follow-up. The competitive inhibition of HO by synthetic metalloporphyrins offers an even simpler solution, but the level of efficacy achieved with the doses and compounds used so far are not comparable with that of phenobarbital. For the time being, phenobarbital is recommended for population groups with high risk of severe neonatal jaundice, or scarcity of resources for the management of neonatal jaundice with phototherapy and exchange transfusion.