New Ballard Score, expanded to include extremely premature infants

Fetal Brain MRI: Segmentation and Biometric Analysis of the Posterior Fossa

This paper presents a novel approach to fetal magnetic resonance image segmentation and biometric analysis of the posterior fossa's midline structures. We developed a semi-automatic segmentation method (based on a region growing technique) and tested the algorithm on images of 104 normal fetuses. Using the segmented regions of interest (posterior fossa, vermis, and brainstem), we computed four relative area ratios. Statistical and clinical analysis of our results showed that the relative development of these structures appears to be independent of pregnancy term. In an additional study of 23 pathological cases, one of the four measurements was always significantly different from the corresponding value observed in normal cases.

Factors influencing levels of 17-hydroxyprogesterone in very low birth weight infants and the relationship to death and IVH

OBJECTIVES

17-Hydroxyprogesterone, an intermediary hormone in cortisol synthesis, has been shown to be elevated in premature infants. However, the relationship between levels of 17-hydroxyprogesterone with death and intraventricular hemorrhage has not been extensively explored. The objective of this study was to determine the factors influencing 17-hydroxyprogesterone and determine if there is an association between intraventricular hemorrhage, mortality, and levels of 17-hydroxyprogesterone in a population of very low birth weight infants.

STUDY DESIGN

Cohort study of very low birth weight infants cared for at a single level 3 NICU during a 1-year period from July 2001 to July 2002. Infants had a minimum of one screen for 17-hydroxyprogesterone and one cranial sonogram. 17-Hydroxyprogesterone was measured on the fifth day of life and at 2 to 4 weeks of life as part of the State of Delaware Newborn Screening Program. Statistical analysis included chi(2), Pearson correlation, multiple-linear regression, and logistic regression.

RESULTS

Levels of 17-hydroxyprogesterone were higher at the time of the first screen compared to the second screen (28.3+/-25.6 vs 17.0+/-18.0 ng/ml, p=0.01), respectively. After controlling for potential confounding variables, gestational age, T(4), and prenatal steroids were all independently associated with 17-hydroxyprogesterone. However, logistic regression analysis showed no association between a 1 log increase in levels of 17-hydroxyprogesterone with the outcomes of death (odds ratio 1.8, 95% CI 0.6 to 5.6), severe IVH (0.7, 0.3 to 1.7), and death and/or severe intraventricular hemorrhage (0.9, 0.4 to 2.1).

CONCLUSIONS

In our population of very low birth weight infants, low gestational age, low T(4), and prenatal steroids were all associated with an elevation in levels of 17-hydroxyprogesterone. High levels of 17-hydroxyprogesterone were not associated with death and/or severe IVH. Our data indicate that factors such as gestational age and antenatal steroids must be considered when interpreting 17-hydroxyprogesterone results from newborn screening.

Transient adrenocortical insufficiency of prematurity and systemic hypotension in very low birthweight infants

OBJECTIVES

A proportion of preterm, very low birthweight (VLBW, < 1500 g) infants may show inadequate adrenal response to stress in the immediate postnatal period. The human corticotrophin releasing hormone (hCRH) stimulation test was used to: (a) determine the relation between pituitary-adrenal response and systemic blood pressure in these infants; (b) characterise the endocrinological features of transient adrenocortical insufficiency of prematurity (TAP).

STUDY DESIGN

A total of 226 hCRH tests were performed on 137 VLBW infants on day 7 and 14 of life in a tertiary neonatal centre.

RESULTS

Basal, peak, and incremental rise in serum cortisol (Delta Cort(0-30)) on day 7 were associated significantly with the lowest systolic, mean, and diastolic blood pressures recorded during the first two weeks of life (r > 0.25, p < 0.005). These cortisol concentrations also correlated significantly but negatively with the maximum and total cumulative dose of dopamine (r > -0.22, p < 0.02), dobutamine (r > -0.18, p < 0.04), and adrenaline (r > -0.26, p < 0.004), total volume of crystalloid (r > -0.22, p < 0.02), and duration of inotrope treatment (r > -0.25, p < 0.006). Multivariate regression analysis of significant factors showed that the lowest systolic, mean, and diastolic blood pressures remained independently associated with serum cortisol (basal, peak, and Delta Cort(0-30)) on day 7. Hypotensive infants requiring inotropes (group 2) were significantly less mature and more sick than infants with normal blood pressure (group 1). The areas under the ACTH response curves were significantly greater in group 2 than in group 1, on both day 7 (p = 0.004) and day 14 (p = 0.004). In contrast, the area under the cortisol response curve was significantly greater in group 1 than in group 2 on day 7 (p = 0.001), but there was no significant difference between the two groups on day 14. In addition, serum cortisol at the 50th centile in hypotensive infants had high specificity and positive predictive value (0.80-0.93 and 0.81-0.89 respectively) for predicting early neonatal hypotension.

CONCLUSIONS

This study characterises the fundamental endocrinological features of TAP: normal or exaggerated pituitary response; adrenocortical insufficiency; good recovery of adrenal function by day 14 of postnatal life. The results also provide the centiles of serum cortisol for hypotensive patients and infants with normal blood pressure, and show a significant relation between serum cortisol and blood pressure in VLBW infants.

Peri-intraventricular hemorrhage in newborns weighing less than 1500 grams: comparative analysis between 2 institutions

PURPOSE

This study aims to characterize the peri-intraventricular hemorrhages in the neonatal period in very low birth weight newborns in 2 institutions that provide neonatal tertiary assistance.

METHOD

This was a comparative and observational study in 2 neonatal intensive care units, the Maternity Hospital of Campinas and the "Centro de Aten o Integrada Sa de da Mulher" of the State University of Campinas, from December 01, 1998 to November 30, 1999. We examined 187 newborns for peri-intraventricular hemorrhages, using transfontanel ultrasound (76 and 11 respectively at the first and second unit), and classified them into 4 grades. We observed their gender, intrauterine growth, weight, and gestational age at birth.

RESULTS

We diagnosed 34 cases of peri-intraventricular hemorrhages (13 and 21, respectively), and both groups differed as to the birth weight and the adequacy of weight to the gestational age at birth. There was no difference in the prevalence or extent of peri-intraventricular hemorrhages among cases. There was a statistically significant occurrence of lower birth weight at gestational ages of less than 30 weeks.

CONCLUSIONS

The prevalence of peri-intraventricular hemorrhages in our study was compared to that reported in the world literature. Although the cases of the second institution had a smaller mean birth weight, the prevalence of peri-intraventricular hemorrhages was similar to that at the first institution, probably because in the first one, 69% of the gestational ages of the neonates with hemorrhage were less than 30 weeks as compared to 48% in the second one. We stress the importance of the ultrasonographic method for diagnosing peri-intraventricular hemorrhages in very low birth weight newborns.

Auricular anthropometry of Hong Kong Chinese babies

OBJECTIVES

To provide a database of the auricular measurements of Chinese infants born in Hong Kong.

DESIGN

Prospective cross-sectional study.

SETTING AND SAMPLE POPULATION

A total of 2384 healthy singleton, born consecutively at the Prince of Wales Hospital and the Union Hospital from October 1998 to September 2000, were included in the study. The range of gestation was 33-42 weeks.

MEASUREMENTS AND RESULTS

Measurements included ear width (EW), ear length (EL) and ear position (EP). The data show generally higher values for males in the parameters measured. When compared with previously published data for Caucasian and Jordanian term babies, Chinese babies have shorter EL. The ears were within normal position in nearly all our infants.

CONCLUSION

The human ear appears to grow in a remarkably constant fashion. This study establishes the first set of gestational age-specific standard of the ear parameters for Chinese new-borns, potentially enabling early syndromal diagnosis. There are significant inter-racial differences in these ear parameters.

Pesquisa sobre mortalidade perinatal no Brasil: revisão da metodologia e dos resultados

A mortalidade perinatal persiste como relevante evento em saúde pública, demandando estudos epidemiológicos, tanto para definir sua magnitude e variações temporais, como para identificar seus determinantes e apontar as intervenções adequadas. Existem ainda questões conceituais e metodológicas controversas, gerando heterogeneidade nos estudos e prováveis vieses. No Brasil, nos últimos anos, desponta uma produção crescente sobre o tema, principalmente no Sudeste e Sul. Foram revistos 24 artigos de 1996 a 2003, focalizando: definições e classificações utilizadas, fontes de dados, desenhos de estudo, formas de aferição das variáveis, modelos de análise estatística e principais resultados. A revisão mostrou a progressiva utilização de bancos de dados informatizados, principalmente o SINASC e o SIM, o pequeno número de estudos sobre natimortalidade, a incorporação ainda incipiente das classificações de causas e a discordância em relação a alguns fatores de risco.

Admission thyroid evaluation in very-low-birth-weight infants: association with death and severe intraventricular hemorrhage

OBJECTIVES

To determine if thyroxine (T(4)) and thyrotropin (TSH) levels, measured at the time of admission to the neonatal intensive care unit, are associated with the outcomes of death and/or severe intraventricular hemorrhage (IVH).

STUDY DESIGN

Blood for total T(4) and TSH was obtained upon admission to the neonatal intensive care unit in infants with birthweights less than 1500 g. Infants were followed until hospital discharge. Statistical analysis included one-way analysis of variance, Pearson correlation, and logistic regression. Data are expressed as mean +/- standard deviation (SD).

RESULTS

One hundred twenty-two infants were enrolled. The mean gestational age of the study population was 27 +/- 2.8 weeks. Both T(4) (R = 0.25, p < 0.01) and TSH (R = 0.39, p < 0.01) at the time of admission correlated with gestational age. Infants who died and/or had severe IVH (n = 31) had lower T(4) (5.0 +/- 2.1 vs. 8.4 +/- 4.1 microg/dL, p < 0.01) and lower TSH (5.5 +/- 6.0 vs. 18.1 +/- 18.1 microIU/mL, p = 0.03) at the time of admission compared to infants who survived without severe IVH. After controlling for gestational age, low T(4) remained associated with an increased odds of death and/or severe IVH (odds ratio for every 1 microg/dL decrease in T(4): 1.4, 95% confidence interval 1.1-1.7).

CONCLUSIONS

Our data show that both low total T(4) and TSH, measured at the time of nursery admission, are associated with death and severe intraventricular hemorrhage. Our data suggest that it may be feasible to design a study of early T(4) supplementation to determine potential benefit in infants with the lowest T(4) values rather than treating based on associated factors such as gestational age.

The role of parenteral lipids in supporting gluconeogenesis in very premature infants

We have previously demonstrated that very premature infants receiving glucose at 17 micromol/kg min plus appropriate supply of parenteral lipids (Intralipid) and amino acids (TrophAmine) maintained normoglycemia by glucose produced primarily via gluconeogenesis. The present study addressed the individual roles of parenteral lipids and amino acids in supporting gluconeogenesis. Fourteen premature infants (993 +/- 36 g 27 +/- 1 wk) (mean +/- SE) were studied for 8 h on d 5 +/- 1 of life. All infants were receiving standard TPN prior to the study. At start of study, the glucose infusion rate was decreased to approximately 17 micromol/kg min and either Intralipid (g + AA; n = 8) or TrophAmine (g + IL; n = 6) was discontinued. Data from 14 previously studied infants receiving glucose (approximately 17 micromol/kg min) + TrophAmine + Intralipid (g + AA + IL) are included for comparison. Gluconeogenesis was measured by [U-13 C]glucose, (g + AA) and (8 infants of the g + AA + IL group) or [2-13C]glycerol, (g + IL) and (6 infants of the g + AA + IL group). Infants studied by the same method were compared. Withdrawal of Intralipid resulted in decreased gluconeogenesis, 6.3 +/- 0.9 (g +AA) vs. 8.4 +/- 0.7 micromol/kg min (g + AA + IL) (p = 0.03). Withdrawal of TrophAmine affected neither total gluconeogenesis, 7.5 +/- 0.8 vs. 7.9 +/- 0.9 micromol/kg min nor gluconeogenesis from glycerol, 4.4 +/- 0.6 vs. 4.9 +/- 0.7 micromol/kg min (g+ IL and g + AA + IL groups, respectively). In conclusion, in parenterally fed very premature infants, lipids play a primary role in supporting gluconeogenesis.

Escore CRIB, peso ao nascer e idade gestacional na avaliação do risco de mortalidade neonatal

OBJETIVO: Avaliar a mortalidade dos recém-nascidos de muito baixo peso em uma UTI neonatal conforme as variações do escore CRIB (Clinical Risk Index for Babies), do peso de nascimento e da idade gestacional em determinado período. MÉTODOS: O escore CRIB foi aplicado seqüencial e prospectivamente em todos os recém-nascidos com peso de nascimento <1.500 g e/ou idade gestacional <31 semanas, em maternidade de um hospital universitário de Londrina, no período de janeiro de 1997 a dezembro de 2000. Os critérios de exclusão foram: óbitos antes de 12 horas de vida, os recém- nascidos com malformações congênitas incompatíveis com a sobrevida e os recém- nascidos encaminhados de outros serviços. RESULTADOS: Foram incluídos no estudo 284 recém-nascidos. O peso médio de nascimento foi de 1.148±248 g (mediana =1.180 g); a idade gestacional média foi de 30,2±2,4 semanas (mediana =30,0) e o CRIB médio foi de 3,8±4,4 (mediana =2,0). A mortalidade neonatal foi de 23,2% diferindo conforme peso <750 g (72,7%), IG<29 semanas (57,1%) e CRIB>10 (79,4%). A curva ROC (Receiver Operator Characteristic) para os valores de CRIB, peso de nascimento e idade gestacional gerou áreas sob a curva de 0,88, 0,76 e 0,81, respectivamente. Na análise bivariada, o CRIB, peso e idade gestacional mostraram-se preditores de mortalidade, sendo o escore CRIB>4 o de melhor resultado com sensibilidade de 75,8%, especificidade de 86,7%, valor preditivo positivo de 63,3% e valor preditivo negativo de 92,2%. CONCLUSÕES: Os recém-nascidos com peso de nascimento <750 g, idade gestacional <29 semanas e escore CRIB>10 tiveram maiores taxas de mortalidade, sendo o escore CRIB>4 o que representou melhor poder preditivo quando comparado com peso ao nascer e idade gestacional.

NICHD neonatal research network: contributions and future challenges

The establishment of the National Institute of Health and Human Development Neonatal Research Network in 1986 was an acknowledgement by the medical community of the need to rigorously perform patient-oriented research in neonates. The limit of viability was being pushed below 26 weeks' gestation by physicians willing to try almost anything to save their extremely low gestational age patients and/or by parents who were willing to accept survival at almost any cost. Too often new treatments or procedures had become standard therapies before efficacy and/or safety had been evaluated. During its first 15 years, the Network has conducted randomized, controlled trials and prospective observational studies focused on such major neonatal issues as brain injury, neuroprotection, late-onset infection, bronchopulmonary dysplasia, severe hypoxic respiratory failure, postnatal growth and nutrition, and long-term neurodevelopmental outcome. This paper reviews the Network's investigative activities during that time, highlights some of the lessons learned in its attempts to identify clinically relevant outcomesthat would change clinical practice, and addresses future challenges.

Facial anthropometry of Hong Kong Chinese babies

OBJECTIVES

To provide a database of the craniofacial measurements of Chinese infants born in Hong Kong.

DESIGN

Prospective cross-sectional study.

SETTING AND SAMPLE POPULATION

A total of 2371 healthy singleton, born consecutively at the Prince of Wales Hospital and the Union Hospital from June 1998 to June 2000, were included in the study. The range of gestation was 33-42 weeks.

MEASUREMENTS AND RESULTS

Measurements included facial width (FW), facial height (FH), nasal length (NL), nasal width (NW), and length of the philtrum (PhilL). The facial, nasal, nasofacial and nasozygomatic indices were derived. The data show generally higher values for males in the parameters measured. The various indices remained remarkably constant and did not vary significantly between the two genders or with gestation. When compared with previously published data for white people term babies, Chinese babies have similar NW but shorter philtrum length.

CONCLUSION

The human face appears to grow in a remarkably constant fashion as defined by the various indices of facial proportions. This study establishes the first set of gestational age-specific standard of such craniofacial parameters for Chinese new-borns, potentially enabling early syndromal diagnosis. There are significant inter-racial differences in these craniofacial parameters.

The NICHD neonatal research network: changes in practice and outcomes during the first 15 years

The National Institute of Child Health and Human Development (NICHD) Neonatal Research Network was founded in 1986 to perform trials that, because of their size and complexity, were beyond the scope of a single center and required the expertise and resources of many collaborating centers. This report briefly documents changes in mortality, selected morbidities, and therapies amongst Network centers. The Network registry incorporating perinatal and neonatal data on all infants with a birth weight 501-1500 g cared for at participating centers served as the database. Mortality and selected morbidities were compared for 3 time periods, 1987/1988, (7 centers 1,765 infants, presurfactant); 1993/1994 (12 centers, 4,593 infants, postsurfactant and moderate antenatal corticosteroid utilization); and 1999/2000 (15 centers, 5,848 infants, postsurfactant and widespread corticosteroid use). Detailed outcomes for infants with birth weights between 501 and 800 g, and gestational ages of 23 to 25 weeks are also presented because they dramatically document the changes over time. Mortality for the entire cohort decreased from 23% in 1987/1988 to 17% in 1993/1994 and 14% in 1999/2000. Between 1987/1988 and 1999/2000 mortality prior to discharge, decreased from 66% to 45% for infants weighing 501-750 g; from 34% to 12% for birth weight between 751 to 1000 g, and from 13% to 7% for infants between 1001 and 1500 g. Mortality was higher in boys. Survival free of major morbidity (chronic lung disease/bronchopulmonary dysplasia, necrotizing enterocolitis or grade III/IV intraventricular hemorrhage) did not change significantly over time. Since the inception of the Network, multiple births have increased from 18% to 26%; deliveries by Cesarean section from 47% to 57%, and antenatal corticosteroid use increased from 16% to 79%. Surfactant, which was not used prior to 1990, is now given to 57% of the infants, including 87% with birth weights between 501 and 750 g. There have been significant decreases in the incidence of grade III-IV intraventricular hemorrhage from 18% in 1987/1988 to about 11% since 1993/1994, and periventricular leukomalacia from 8% to 3%. However, other morbidities, including necrotizing enterocolitis, patent ductus arteriosus, and late onset sepsis, have not changed substantially. Advances in perinatal care within NICHD Network centers have resulted in marked improvements in survival. Further advances are required to increase survival free of neonatal morbidity or neurodevelopmental impairment.

Prediction of extrauterine growth retardation (EUGR) in VVLBW infants

BACKGROUND

Long-term growth failure in very very low birth weight (VVLBW) infants is a common complication of extreme prematurity. Critical illnesses create challenges to adequate nutriture.

PURPOSE

To identify predictors of extrauterine growth retardation (EUGR) in VVLBW infants and to evaluate their nutritional intake and subsequent growth.

STUDY DESIGN

A 4-year retrospective chart review of 221 infants <or=1000 g birth weight and <or=29 weeks gestational age who were admitted within 24 hours of birth, were free of major congenital anomalies and survived at least 7 days. Daily intakes and anthropomorphic data were collected and analyzed. Significant events during hospitalization were documented.

RESULTS

Mean energy and protein intakes during hospitalization did not reach recommendations of 120 kcal/kg/d and 3.0 g/kg/day. In utero growth rates could not be consistently reached or sustained. As expected, BW (as measured by BW percentile score) was highly predictive of EUGR (p<0.001). When the independent effect of other predictors of EUGR was considered, only days of total parenteral nutrition (p<0.001) and HC percentile at return to birth weight (p<0.001) made a significant contribution to the prediction of EUGR, once the effect of BW was taken into account.

Weight of preterm newborns during the first twelve weeks of life

A longitudinal and prospective study was carried out at two state-operated maternity hospitals in Belo Horizonte during 1996 in order to assess the weight of preterm appropriate-for-gestational-age newborns during the first twelve weeks of life. Two hundred and sixty appropriate-for-gestational-age preterm infants with birth weight <2500 g were evaluated weekly. The infants were divided into groups based on birth weight at 250-g intervals. Using weight means, somatic growth curves were constructed and adjusted to Count's model. Absolute (g/day) and relative (g kg-1 day-1) velocity curves were obtained from a derivative of this model. The growth curve was characterized by weight loss during the 1st week (4-6 days) ranging from 5.9 to 13.3% (the greater the percentage, the lower the birth weight), recovery of birth weight within 17 and 21 days, and increasingly higher rates of weight gain after the 3rd week. These rates were proportional to birth weight when expressed as g/day (the lowest and the highest birth weight neonates gained 15.9 and 30.1 g/day, respectively). However, if expressed as g kg-1 day-1, the rates were inversely proportional to birth weight (during the 3rd week, the lowest and the highest weight newborns gained 18.0 and 11.5 g kg-1 day-1, respectively). During the 12th week the rates were similar for all groups (7.5 to 10.2 g kg-1 day-1). The relative velocity accurately reflects weight gain of preterm infants who are appropriate for gestational age and, in the present study, it was inversely proportional to birth weight, with a peak during the 3rd week of life, and a homogeneous behavior during the 12th week for all weight groups.

Changes in neurotrophin levels in umbilical cord blood from infants with different gestational ages and clinical conditions

Apoptotic neuronal loss may be responsible for altered brain development associated with prematurity and perinatal insults. Neurotrophins play crucial roles in protecting neurons from entering or progressing along an apoptotic pathway. The present study examined levels of neurotrophins in human umbilical cord blood from infants at different gestational ages and clinical conditions. We collected 60 samples of cord blood and categorized them accordingly into three gestational age groups: group A (24-28 wk), group B (29-35 wk), and group C (>/=36 wk). Neurotrophin levels were determined by using brain-derived neurotrophic factor (BDNF) and neurotrophin 3 (NT3) ELISA. Clinical data were obtained by medical chart analysis. The BDNF levels were 884 +/- 386, 1421 +/- 616, and 2190 +/- 356 pg/mL in group A, group B, and group C, respectively. Significant differences were found between groups A and B (p = 0.038), groups A and C (p = 0.0001), and groups B and C (p = 0.001). Infants with severe intraventricular hemorrhage had significantly lower cord blood BDNF levels (925 +/- 513 pg/mL) compared with their normal counterparts (1650 +/- 674 pg/mL; p = 0.021). NT3 levels did not show significant change either across gestational ages or with the presence of intraventricular hemorrhage. Cord blood levels of BDNF may reflect the degree of neural maturity in premature infants. Interestingly, when a complete course of antenatal steroids was given, BDNF and NT3 cord blood levels were higher than when no steroid was given. Increased neurotrophins levels may also mediate improved neurodevelopmental outcome in infants who received antenatal steroids.

Updated gestational age specific birth weight, crown-heel length, and head circumference of Chinese newborns

OBJECTIVE

To construct gestation specific standards of birth weight, crown-heel length, and head circumference of Chinese infants.

DESIGN

A prospective cross sectional population study.

METHODS

The birth weight, crown-heel length, and head circumference were prospectively measured using standard equipment in newborns delivered at 24-42 weeks gestation in the maternity units of 10 public hospitals and two private hospitals in Hong Kong. The findings were used to construct gestation specific standards of these variables. The LMS method using maximum penalised likelihood was used to perform model fitting. The results were compared with those obtained from a cohort of infants born in the same locality between 1982 and 1986.

RESULTS

From October 1998 to September 2000, a total of 10 032 infants were measured, representing 9.6% of the total deliveries in Hong Kong during that period. An extra 307 infants with gestation < or = 35 weeks were recruited from October 2000 to June 2001. Each of the three variables showed a normal distribution at each gestational week. Gestation specific reference standards for each variable were constructed for male and female infants separately. Comparison with the 1982-1986 cohort showed a significant secular trend to increased birth weight. The trend was small, but significant, for crown-heel length and head circumference.

CONCLUSION

These growth standards will provide useful references for the care of newborns of ethnic Chinese origin. These standards, especially that for birth weight, should be updated regularly.

Characterization of newborns with nonimmune hydrops fetalis admitted to a neonatal intensive care unit

PURPOSE

To determine the incidence and characteristics of nonimmune hydrops fetalis in the newborn population.

METHOD

A retrospective study of the period between 1996 and 2000, including all newborns with a prenatal or early neonatal diagnosis of nonimmune hydrops fetalis, based on clinical history, physical examination, and laboratory evaluation. The following were analyzed: prenatal follow-up, delivery type, gender, birth weight, gestational age, presence of perinatal asphyxia, nutritional classification, etiopathic diagnosis, length of hospital stay, mortality, and age at death.

RESULTS

A total of 47 newborns with hydrops fetalis (0.42% of live births), 18 (38.3%) with the immune form and 29 (61.7%) with the nonimmune form, were selected for study. The incidence of nonimmune hydrops fetalis was 1 per 414 neonates. Data was obtained from 21 newborns, with the following characteristics: 19 (90.5%) were suspected from prenatal diagnosis, 18 (85.7%) were born by cesarean delivery, 15 (71.4%) were female, and 10 (47.6%) were asphyxiated. The average weight was 2665.9 g, and the average gestational age was 35 3/7 weeks; 14 (66.6%) were preterm; 18 (85.0 %) appropriate delivery time; and 3 (14.3%) were large for gestational age. The etiopathic diagnosis was determined for 62%, which included cardiovascular (19.0%), infectious (9.5%), placental (4.8%), hematologic (4.7%), genitourinary (4.8%), and tumoral causes (4.8%), and there was a combination of causes in 9.5%. The etiology was classified as idiopathic in 38%. The length of hospital stay was 26.6 +/- 23.6 days, and the mortality rate was 52.4%.

CONCLUSIONS

The establishment of a suitable etiopathic diagnosis associated with prenatal detection of nonimmune hydrops fetalis can be an important step in reducing the neonatal mortality rate from this condition.

Nutritional state and growth and functional maturation of the brain in extremely low birth weight infants

OBJECTIVE

It is well-known that an undernutritional status influences central nervous system development in the fetal and early neonatal period. On the other hand, the maturational delay of the central nervous system is reflected as dysmature pattern (DMP) in the neonatal background electroencephalograph (EEG). Therefore, we hypothesized that the postnatal nutritional status influenced electrophysiologic maturation in extremely low birth weight infants (ELBWIs).

METHODS

ELBWIs between 24 and 27 weeks of gestational age who were admitted to Ogaki Municipal Hospital NICU from April 1997 to December 2000 were considered eligible. From the condition of enteral feeding, infants were divided into 2 groups: 1). normal nutritional group (group N), where enteral feeding had been established (100 mL/kg/d) by 3 weeks after birth; 2). undernutritional group (group U), where enteral feeding had not been established by 3 weeks after birth or was discontinued because of clinical problems. Weekly average body weight and head circumference gains were evaluated as nutritional status. EEG records were performed every 2 to 4 weeks until postnatal 15 weeks of age. DMP was defined as the appearance of immature EEG patterns for postconceptional age.

RESULTS

Twenty-one infants had serial EEG recordings; 11 infants belonged to group N and 10 infants to group U. Gestational age, birth weight, and head circumference at birth were not different between the 2 groups. The body weight of group N was significantly heavier than that of group U after 5 postnatal weeks. Similarly, the head circumference of group N was larger than that of group U after 6 weeks of postnatal age. Nine infants demonstrated DMPs. One infant belonged to group N and 8 to group U. DMPs were significantly more frequently found in group U than group N (80% vs 9%). In 6 of the 9 cases, the DMPs lasted until 38 to 40 weeks of postconceptional age. Five of the 6 infants with persistent DMPs suffered from severe undernutritional conditions. The other, who belonged to group N, was treated with corticosteroid for chronic lung disease. In 3 cases, DMPs were observed transiently and their undernutritional status was not so severe.

CONCLUSIONS

Our study indicated that a postnatal undernutritional condition was associated with DMPs in ELBWIs. Undernutritional status may affect electrophysiologic maturation.

Analgesic Effect of Oral Glucose in Neonates

The International Association for the Study of Pain, has defined pain as "an unpleasant sensory and emotional experience connected with actual or potential tissue damage or described in terms of such damage". It was thought that the newborn baby does not experience pain because of incompletely developed nervous system. However, it has been shown that neurological system known to be associated with pain transmission and modulation, is intact and functional. A study was conducted in our center to study the analgesic effect of administration of oral glucose in various concentrations, in neonates undergoing heel punctures, for collection of blood for investigations. This was compared with the analgesic effects of breast milk (which contains lactose). 125 full term normal neonates with no history of birth asphyxia or underlying neurological abnormality, requiring heel punctures for collection of blood for various investigations were selected for the study. They were matched for gestational age, birth weight and sex distribution and divided into 5 groups of 25 each. One group comprised control subjects and was administered sterile water. 3 groups were administered 1 ml of varying strengths of glucose solutions i.e. 10%, 25% and 50% respectively. The last group was given 1 ml of expressed breast milk (EBM). Prior to heel pricks, state of arousal, baseline heart rate (HR) and transcutaneous oxygen saturation (SpO2) were recorded by pulse oximeter in each neonate. Autolet, a mechanical device for capillary sampling, was used for heel pricks to give equal strength of painful stimulus in each procedure. Audio tape recorder was used to record the cry. The oral solution was administered slowly over 30 seconds by means of a syringe placed in the mouth. Heel puncture was done after 2 minutes, taking all aseptic precautions. HR and SpO2 were monitored using pulse oximeter. Pain response was assessed, by recording duration of crying, change in HR, change in SpO2 and facial action score after the procedure. Mean duration of cry and total cry over 5 minutes was significantly less in groups given 25% and 50% glucose solutions as compared to the control group and babies given EBM. Difference in mean increase in HR, fall in SpO2 were statistically significant between control group, EBM group and neonates given 25% and 50% glucose solutions respectively. Compared to control group, all other administered solutions (10%, 25%, 50% glucose and EBM) were found to reduce physiological and behavioral responses in neonates undergoing heel punctures. 25% and 50% glucose solutions were found to have maximal analgesic effect and both were found to be equally effective. EBM and 10% glucose solution have an equal analgesic effect but less than 25% or 50% glucose. This simple, cheap and safe method of oral analgesia can be easily used in neonates undergoing heel prick procedures during routine neonatal care.

Parenteral glycerol enhances gluconeogenesis in very premature infants

We have previously demonstrated that very premature infants receiving total parenteral nutrition maintain normoglycemia primarily by glucose produced via gluconeogenesis and that the lipid emulsion is most important in supporting gluconeogenesis. It is, however, not clear whether this is a result of the glycerol or the fatty acid constituent. The purpose of the present study was to determine the effect of intravenous supplemental glycerol alone on glucose production and gluconeogenesis. Twenty infants (birth weight, 1014 +/- 32 g; gestational age, 27 +/- 1 wk) were studied on d 4 +/- 1 (mean +/- SE). All infants received glucose at 17 micromol/kg x min for 9 h (after an initial study hour with 33 micromol/kg x min). Eight infants received no additional substrate during the study, and 12 infants received supplemental glycerol at 5 (n = 6) or 10 micromol/kg x min (n = 6) over the last 5 h of study. In infants receiving glucose alone, between period 1 (study hours 4-5) and period 2 (study hours 9-10), rates of glucose production ([U-13C]glucose) decreased from 12.9 +/- 1.2 to 7.4 +/- 0.9 micromol/kg x min (p < 0.01). This was the result of decreased glycogenolysis but no change in gluconeogenesis ([U-13C]glucose mass isotopomer distribution analysis) (5.1 +/- 0.6 versus 5.7 +/- 0.4 micromol/kg x min) (ns). Glycerol infusion at 5 and 10 micromol/kg x min, respectively, maintained glucose production (despite comparable decrease in glycogenolysis) by increasing gluconeogenesis from 4.3 +/- 0.2 to 6.3 +/- 0.5 (p < 0.03), and 6.0 +/- 0.7 to 8.8 +/- 0.8 micromol/kg/min (p < 0.01). In very premature infants, parenteral glycerol enhances gluconeogenesis and attenuates time dependent decrease in glucose production.

Antenatal treatment with corticosteroids for preterm neonates: impact on the incidence of respiratory distress syndrome and intra-hospital mortality

CONTEXT

Although the benefits of antenatal corticosteroids have been widely demonstrated in other countries, there are few studies among Brazilian newborn infants.

OBJECTIVE

To evaluate the effectiveness of antenatal corticosteroids on the incidence of respiratory distress syndrome and intra-hospital mortality among neonates with a gestational age of less than 34 weeks.

TYPE OF STUDY

Cross-sectional.

SETTING

A tertiary-care hospital.

PARTICIPANTS

Neonates exposed to any dose of antenatal corticosteroids for fetal maturation up to 7 days before delivery, and newborns paired by sex, birth weight, gestational age and time of birth that were not exposed to antenatal corticosteroids. The sample obtained consisted of 205 exposed newborns, 205 non-exposed and 39 newborns exposed to antenatal corticosteroids for whom it was not possible to find an unexposed pair.

PROCEDURES

Analysis of maternal and newborn records.

MAIN MEASUREMENTS

The primary clinical outcomes for the two groups were compared: the incidence of respiratory distress syndrome and intra-hospital mortality; as well as secondary outcomes related to neonatal morbidity.

RESULTS

Antenatal corticosteroids reduced the occurrence of respiratory distress syndrome (OR: 0.33; 95% CI: 0.21-0.51) and the protective effect persisted when adjusted for weight, gestational age and the presence of asphyxia (adjusted OR: 0.27; 95% CI: 0.17-0.43). The protective effect could also be detected through the reduction in the need for and number of doses of exogenous surfactant utilized and the number of days of mechanical ventilation needed for the newborns exposed to antenatal corticosteroids. Their use also reduced the occurrence of intra-hospital deaths (OR: 0.51: 95% CI: 0.38-0.82). However, when adjusted for weight, gestational age, presence of prenatal asphyxia, respiratory distress syndrome, necrotizing enterocolitis and use of mechanical ventilation, the antenatal corticosteroids did not maintain the protective effect in relation to death. With regard to other outcomes, antenatal corticosteroids reduced the incidence of intraventricular hemorrhage grades III and IV (OR: 0.28; 95% CI: 0.10-0.77).

CONCLUSIONS

Antenatal corticosteroids were effective in the reduction of morbidity and mortality among premature newborns in the population studied, and therefore their use should be stimulated within our environment.

Effect of minimal enteral feeding on splanchnic uptake of leucine in the postabsorptive state in preterm infants

We conducted a controlled, randomized trial to study the effect of minimal enteral feeding on leucine uptake by splanchnic tissues, as an indicator of maturation of these tissues, in preterm infants in the first week of life. Within a few hours after birth, while receiving only glucose, a primed constant infusion of [1-(13)C]-leucine was started and continued for 5 h via the nasogastric tube, whereas 5,5,5 D3-leucine was infused intravenously (for both tracers, priming dose 2 mg/kg, continuous infusion 2 mg/kg/h). Patients were thereafter randomized to receive solely parenteral nutrition (C), parenteral nutrition and 20 mL breast milk/kg/d (BM), or parenteral nutrition and 20 mL formula/kg/d (F). On d 7, the measurements were repeated, after discontinuing the oral intake for 5 h. Fourteen infants were included in group C, 12 in group BM, and 12 in group F. There was no difference in energy intake or nitrogen balance at any time. On d 1, plasma enrichment for the nasogastric tracer was lower than for the intravenous tracer for all three groups, both for leucine and for alpha-keto-isocaproic acid. On d 7, the enrichment for leucine and alpha-keto-isocaproic acid for the nasogastric tracer was lower than for the intravenous tracer for the groups BM and F (BM: 3.65 +/- 1.20 nasogastric versus 4.64 +/- 0.64 i.v.; F: 4.37 +/- 1.14 nasogastric versus 5.21 +/- 0.9 i.v.). In the control group, there was no difference between tracers. The lower plasma enrichment for the nasogastric tracer compared with the intravenous tracer suggests uptake of leucine by the splanchnic tissues. We conclude that minimal enteral feeding--even in low volumes of 20 mL/kg/d--increases the leucine uptake by the splanchnic tissue. We speculate that this reflects a higher protein synthesis of splanchnic tissues in the groups receiving enteral nutrition.

Craniofacial anthropometry of Hong Kong Chinese babies: the eye

OBJECTIVES

To provide a database of the canthal measurements of Chinese infants born in Hong Kong.

DESIGN

Prospective cross-sectional study.

SETTING AND SAMPLE POPULATION

A total of 2,371 healthy singleton, born consecutively at the Prince of Wales Hospital and the Union Hospital from June 1998 to June 2000, were included in the study. The range of gestation was 33-42 weeks.

MEASUREMENTS AND RESULTS

Canthal parameters were measured and included the outer canthal distance (OCD), intercanthal distance (ICD) and palpebral fissure length (PFL). The data generally show higher values for males in the parameters measured. The measurements were also compared with data published overseas. PFL and OCD were significantly larger in Hong Kong Chinese newborn babies, whereas ICD was smaller.

CONCLUSION

This study establishes the first set of gestational age-specific standard of such craniofacial parameters for Chinese newborn babies, potentially enabling early syndromal diagnosis. There are significant inter-racial differences in these canthal parameters.

Placental transfer of naturally acquired, maternal cytomegalovirus antibodies in term and preterm neonates

Maternal antibodies may protect the fetus and neonate against severe forms of CMV-caused disease, therefore this study investigated the efficiency of the placental transfer of naturally acquired, maternal total anti-cytomegalovirus (CMV) IgG and neutralizing antibodies at different gestational ages. The study was conducted on 182 healthy CMV-seropositive Brazilian mothers and their 196 infants who were not infected congenitally with CMV, as determined by CMV detection in urine. The study groups were composed of 44 infants aged 28-30 weeks; 51 infants aged 31-33 weeks; 62 infants aged 34-36 weeks, and 39 infants of gestational age > or = 37 weeks. Quantitative detection of total CMV IgG was carried out using EIA and virus neutralizing titers were determined by a microneutralization assay in sera from mothers and infants. CMV IgG levels and neutralizing titers of the infants correlated with maternal levels (r=0.873 and r=0.841, respectively). The efficiency of placental transfer of these antibodies was enhanced significantly as gestation progressed until 34-36 weeks, when values similar to those of full-term infants (90-100%) were found. Transfer ratios were significantly higher for neutralizing compared to total CMV IgG antibodies at gestational age 31-33 weeks (100% vs. 84%, respectively) and at gestational age 28-30 weeks (75% vs. 60%, respectively). We conclude that placental transfer of naturally acquired maternal CMV neutralizing and total CMV IgG antibodies are similarly efficient above 34 weeks of gestational age. At less than 34 weeks of gestational age, transfer of neutralizing antibodies may be favored and these antibodies reach the neonatal serum of 99% of these premature infants.

Growth and energy and protein intake of preterm newborns in the first year of gestation-corrected age

CONTEXT

There are few longitudinal studies that analyze the growth and nutritional status parameters of children born prematurely.

OBJECTIVE

To evaluate the growth and dietary intake of preterm newborns in the first year of gestation-corrected age.

DESIGN

Prospective clinical study.

SETTING

Tertiary care hospital.

PATIENTS

19 children (7 male) who were born prematurely, with birth weight between 1000 g and 2000 g, which was adequate for the gestational age.

PROCEDURES

At 3, 6, 9 and 12 months of gestation-corrected age, children were evaluated in relation to weight, height and cephalic perimeter, using the National Center for Health Statistics as the standard reference, and the Rozalez-Lopez and Frisancho standards for brachial perimeter and triceps and subscapular skinfolds. The calculated dietary intake was compared to the Recommended Dietary Allowances.

MAIN MEASUREMENTS

The Z score was calculated for the weight/age, height/age and weight/height relationships, and the percentiles of the perimeters and skinfolds were considered. Dietary intake records were made using the 24-hour Dietary Recall and the Food Frequency Intake Questionnaire methods. The Virtual Nutri software was used to calculate energy and protein intake.

RESULTS

The weight/age, height/age and weight/height relationships and the brachial perimeter and triceps skinfold were statistically greater in the first semester in relation to the second. The cephalic perimeter remained above the 50th percentile for the ages studied and there was no difference in the subscapular skinfold between the first and second semesters, remaining below the 50th percentile. The calorie and protein intake, although statistically lower in the first than in the second semester, always remained above the recommended.

CONCLUSIONS

The pace of growth is greater in the first semester than in the second, not reaching the standard expected for full-term newborns, with the exception of the cephalic perimeter, which remains adequate. Calorie/protein intake shows an inverse relationship with growth speed, remaining above the recommended for full-term newborns, although with difficulty in depositing subcutaneous fat, in spite of the high caloric intake.

Brainstem auditory evoked responses in term small for gestational age newborn infants born to undernourished mothers

Our aim was to assess the effect of intrauterine growth retardation on neurosensory development by evaluating brainstem auditory evoked responses (BAER) in term small for gestational age (SGA) newborn infants born to undernourished mothers. This prospective clinical study included 25 singleton healthy SGA newborn infants born between 38 and 41 weeks to undernourished mothers (weight <45kg, height <145cm, haemoglobin <8g/dl, and serum albumin <2.5g/dl). An equal number of age- and sex-matched appropriate for gestational age newborn infants born to healthy mothers served as controls. Mothers with other risk factors and newborns with complications during delivery or immediate newborn period were excluded. BAER was recorded within first 3 days of life. Interpeak latency (IPL), absolute peak latency (APL) and amplitudes of various waveforms were determined and compared between the groups. No statistically significant differences were observed for the mean interpeak and absolute latencies between term SGA and AGA infants (p>0.05). The absolute peak latency (wave V) and central conduction time (I-V interval) were borderline prolonged in the study group compared with controls (p=0.051 and 0.088 respectively). Using multiple regression analysis, maternal haemoglobin was identified to be the only parameter having a negative correlation with both IPL (waves I-V) (F[1,46]=4.12, p=0.048) and APL (wave V) (F[1,46]=5.80, p=0.02). Maternal undernourishment may have a minor effect on intrauterine development of the auditory brainstem. Maternal haemoglobin is the only factor significantly associated with these changes.

Hypoglycemia and the full-term newborn: how well does birth weight for gestational age predict risk?

OBJECTIVE

To determine whether anthropometric characteristics could be used to accurately predict risk of hypoglycemia in full-term newborns during the early post-birth period.

DESIGN

Descriptive, utilizing newborn anthropometric measurements singly and in combination to determine risk of neonatal hypoglycemia. The following measurements were obtained twice for each newborn: weight, head circumference, chest circumference, abdominal circumference, mid-arm circumference, thigh circumference, and length. The investigator was blind to all measurements except weight.

SETTING

Mothers' rooms or the newborn nursery in a community hospital.

INTERVENTIONS

All measurements were obtained twice, and a physical examination was completed on each newborn by the principal investigator. These newborns were classified as large-, average-, and small-for-gestational age, using a tool typically used in many newborn nurseries.

SAMPLE

One hundred fifty-seven full-term newborns (94 White and 63 African American).

MAIN OUTCOME MEASURES

The differences in anthropometric measurements by race and gender were calculated using two-way analysis of variance. The risk of hypoglycemia was calculated using logistic regression modeling.

RESULTS

There were significant differences in measurements by race and by gender. Additionally, there was a subset of newborns classified as average for gestational age who had an increased risk of hypoglycemia (OR = 4.17, 95% CI = 1.33-13.08). Newborns with a mid-arm circumference/head circumference ratio that varied from .26 to .29 have an odds ratio of 6.10 (95% CI = 1.89-19.66) for risk of hypoglycemia. Plotting a newborn's birth weight on a published fetal growth curve clearly did not accurately predict his or her risk of hypoglycemia.

CONCLUSIONS

These findings indicate that extremes in newborn birth weight are not always correctly defined, may vary by race and ethnic group, and may not be the best method for determining under- or overnourishment and risk of neonatal hypoglycemia.

Outcome of very-low-birth-weight infants in a developing country: a prospective study from the western region of Turkey

OBJECTIVE

To illustrate neonatal outcomes, including morbidity, birth weight and gestational age-specific mortality, and care practices for very-low-birth-weight infants admitted to our tertiary neonatal intensive care unit in Turkey and compare these with the corresponding data from recent reports from developed countries.

METHODS

Perinatal data were collected prospectively from January 1996 to December 2000. Perinatal events and the neonatal course to 120 days of life, discharge, or death were evaluated.

RESULTS

Of 173 infants, 82% survived until discharge to home or to 120 days of life. Survival was 13% for infants of 501-750 g at birth, 74% for those of 751-1000 g, 92% for those of 1001-1250 g and 87% for those of 1251-1500 g. Mortality rates were greater for male than for female infants (25% vs. 12%). The mean birth weight was 1218 (450-1500) g and the mean gestational age was 29.8 (23-36) weeks. The birth weight and gestational age distributions showed that the majority of infants (48%) weighed 1251-1500 g and were between 28 and 31 weeks' gestation (57%). Antenatal steroids were administered to only 19% of mothers. The overall Cesarean section rate was 77%. Respiratory distress syndrome was diagnosed in 36% and surfactant was administered to 98% of these infants. The rate of ventilator support was 54% for a mean duration of 9 days. Air leak syndromes were diagnosed in only nine infants (5%). Severe intracranial hemorrhage (grade > II) and periventricular leukomalacia developed in 9% of infants. Four infants had evidence of chronic lung disease. Retinopathy of prematurity (stage > II) was noted in only one infant, and proven necrotizing enterocolitis (Bell's classification stage > 2) was not observed. The rate of survival without major morbidity was 91%. The mean hospital stay was 40 days for survivors and 19 days for infants who died.

CONCLUSION

Despite marked differences in socioeconomic conditions and tertiary care facilities, the mortality (except in the smallest babies) and morbidity rates were comparable with those of recent studies from developed countries.

[Energy intake, maternal nutritional status and intrauterine growth retardation]

To explore the association between low caloric intake during pregnancy and intrauterine growth retardation (IUGR), a case-control study with 264 cases and 892 controls was conducted in three maternity hospitals in Mexico City from January to August 1995. Nutritional information on pregnancy was recorded using a previously validated food frequency questionnaire. After adjusting for other known maternal risk factors in the non-conditional logistic regression analysis, for the total sample, caloric intake did not present a direct effect on IUGR (OR: 0.99; CI 95%: 0.99-1.00). However the odds ratios were as follows for women: with low pre-gestational weight (OR: 2.31; CI 95%: 1.59-3.36), in first gestation (OR: 1.72; CI 95%: 1.18-2.51), with low birth weight infants (OR: 3.54; CI 95%: 1.93-6.46), and presenting hypertension during pregnancy (OR: 1.61; CI 95%: 1.00-2.59).

Physical status of newborns and neonatal outcome

OBJECTIVE

To determine the extent to which physical status at birth is associated with neonatal mortality and the causes of mortality vis-a-vis size at birth and gestational age.

METHOD

11,223 consecutive live births completing 26 weeks of gestation and weighing > or = 500 gm were included in the study. Birth weight and chest circumference were recorded as per WHO guidelines. Gestational age was calculated on the basis of L.M.P. and the new Ballard's score. Deaths occurring in the hospital within 28 days were recorded. Percentile values of gestational age specific birth weights were calculated separately for singletons and multiple births. Percentage of SGA was calculated with reference to WHO recommended values. Birth weight-gestational age-specific mortality rates were calculated at 2 wk and 500 gm intervals.

RESULT

Low-birth-weight babies constituted 39.8% of the total, much in excess of WHO recommended figure of 15%. 76% deaths occurred among LBW babies and 56.2% among preterms. Mortality showed remarkable decline as the birth weight increased to 2,000 gm. The lowest mortality was among singletons weighing 2,500-3,000 gm and of 38-40 weeks gestation. Prevalence of SGA at 40 and 42 weeks were 73.7% and 83.6% respectively. But, if SGA babies not categorised as LBW were excluded, the values came down to 32% and 36% respectively. 36% of all deaths occurred during the first 24 hrs of birth; asphyxia and related causes contributing to 50% of it.

CONCLUSION

Cut-off value of 2,000 gm instead of 2,500 gm for birth weight may be preferable in countries where most LBW babies are SGAs. Simultaneously, deaths in non-LBW babies due to perinatal causes contribute sgnificantly to total neonatal mortality and need due attention through sensitising obstetricians in essential newbom care and timely Intervention.

Parachute and lateral propping reactions in preterm children

A non-controlled, prognostic cohort study was performed with the aim of establishing markers of neurological development and defining a clinical and epidemiological profile of preterm newborns at 3, 6, 9, and 12 months of gestation-corrected age in terms of parachute and lateral propping reactions. Newborns with gestational age of up to 36 weeks and 6 days, weighing 2,000 g or less at birth, were included in the study At 6 months of age, parachute and lateral propping reactions were present in 8.1% of the patients. At 9 months, the parachute reaction was present in 87.5%, and the lateral propping reaction was present in 90% of the children. It was possible to assess parachute and lateral propping reactions in preterm children in the first year of life. Alterations in trunk-limb coordination may be evidenced in the 1st year of life through postural reactions, which are maintained as prematurity markers until school age.

Central and autonomic system signs with in utero drug exposure

AIMS

To determine risk for central nervous system/autonomic nervous system (CNS/ANS) signs following in utero cocaine and opiate exposure.

METHODS

A multisite study was designed to determine outcomes of in utero cocaine and opiate exposure. A total of 11 811 maternal/infant dyads were enrolled. Drug exposed (EXP) infants were identified by maternal self report of cocaine or opiate use or by meconium testing. Of 1185 EXP, meconium analysis confirmed exposure in 717 to cocaine (CO) only, 100 to opiates (OP), and 92 to opiates plus cocaine (OP+CO); 276 had insufficient or no meconium to confirm maternal self report. Negative exposure history was confirmed in 7442 by meconium analysis and unconfirmed in 3184. Examiners masked to exposure status, assessed each enrolled infant. Using generalised estimating equations, adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated for manifesting a constellation of CNS/ANS outcomes and for each sign associated with cocaine and opiate exposure.

RESULTS

Prevalence of CNS/ANS signs was low in CO, and highest in OP+CO. Signs were significantly related to one another. After controlling for confounders, CO was associated with increased risk of manifesting a constellation of CNS/ANS outcomes, OR (95% CI): 1.7 (1.2 to 2.2), independent of OP effect, OR (95% CI): 2.8 (2.1 to 3.7). OP+CO had additive effects, OR (95% CI): 4.8 (2.9 to 7.9). Smoking also increased the risk for the constellation of CNS/ANS signs, OR (95% CI) of 1.3 (1.04 to 1.55) and 1.4 (1.2 to 1.6), respectively, for use of less than half a pack per day and half a pack per day or more.

CONCLUSION

Cocaine or opiate exposure increases the risk for manifesting a constellation of CNS/ANS outcomes.

The intrauterine environment is a strong determinant of glucose tolerance during the neonatal period, even in prematurity

The aim of this study was to determine the contribution of birth weight and gestational age to glucose tolerance in premature neonates. The study group consisted of 100 premature and/or small-for-gestational age infants. Anthropometric measurements were performed both at birth and at the time of a standardized milk feed carried out at 19.6 +/- 12.1 d (range, 1-65 d) after birth. Fasting and postprandial glucose and insulin levels were measured. Birth weight, as a proxy mirror of the intrauterine environment, was found to influence the glucose concentration following a standardized milk feed (beta = -0.46; P = 0.01 for birth weight z-score with 60-min glucose level), whereas gestational age did not. Small-for-gestational age neonates had higher 60-min insulin levels than appropriate-for-gestational age neonates (115.4 +/- 9.5 vs. 68.4 +/- 14.2; P < 0.05) despite similar glucose levels. Neonates born of mothers who were on antihypertensive treatment were smaller and had a higher insulin secretory response than neonates from normotensive mothers. Postnatal growth velocity (kilograms per day) correlated with birth weight (beta = -0.65; P < 0.0001) and insulin resistance (beta = -0.31; P = 0.0004), independently of each other. This study shows that glucose tolerance of the neonate is determined by weight attained at birth irrespective of gestational age and that maternal blood pressure may influence insulin sensitivity of the newborn. Furthermore, catch-up growth in neonates is determined by birth weight and insulin sensitivity.

Retinopathy of prematurity outcome in infants with prethreshold retinopathy of prematurity and oxygen saturation >94% in room air: the high oxygen percentage in retinopathy of prematurity study

OBJECTIVES

To determine the rate of progression from prethreshold to threshold retinopathy of prematurity (ROP) in infants excluded from Supplemental Therapeutic Oxygen for Prethreshold Retinopathy of Prematurity (STOP-ROP) because their median arterial oxygen saturation by pulse oximetry (SpO2) values were >94% in room air at the time of prethreshold diagnosis and to compare them with infants who were enrolled in STOP-ROP and had median SpO2 < or =94% in room air.

METHODS

Fifteen of the 30 centers that participated in STOP-ROP elected to participate in the High Oxygen Percentage in Retinopathy of Prematurity study (HOPE-ROP) from January 1996 to March 1999. Infants were followed prospectively from the time prethreshold ROP was diagnosed until ROP either progressed to threshold in at least 1 study eye (adverse outcome) or resolved (favorable outcome).

RESULTS

A total of 136 HOPE-ROP infants were compared with 229 STOP-ROP infants enrolled during the same time period from the same 15 hospitals. HOPE-ROP infants were of greater gestational age at birth (26.2 +/- 1.8 vs 25.2 +/- 1.4 weeks) and greater postmenstrual age at the time of prethreshold ROP diagnosis (36.7 +/- 2.5 vs 35.4 +/- 2.5 weeks). HOPE-ROP infants progressed to threshold ROP 25% of the time compared with 46% of STOP-ROP infants. After gestational age, race, postmenstrual age at prethreshold diagnosis, zone 1 disease, and plus disease at prethreshold diagnosis were controlled for, logistic regression analysis showed that HOPE-ROP infants progressed from prethreshold to threshold ROP less often than STOP-ROP infants (odds ratio: 0.607; 95% confidence interval: 0.359-1.026).

CONCLUSIONS

The mechanisms that result in better ROP outcome for HOPE-ROP versus STOP-ROP are not fully understood. It seems that an infant's SpO2 value at the time of prethreshold diagnosis is a prognostic indicator for which infants may progress to severe ROP. When other known prognostic indicators are factored in, the SpO2 is of borderline significance.

Cost-effectiveness and choice of infant transport systems

OBJECTIVE

To compare cost-effectiveness of three types of infant transport models (Emergency Medical Technicians [EMT], Registered Nurses [RN], or Combined Teams [CT] of RNs and Respiratory Therapists) and to derive a decision model to guide choice of a transport system.

RESEARCH DESIGN

A prospective, multicenter, observational study was conducted to compare infant physiologic status before and after transport. Cost-effectiveness analysis from the perspective of the third-party payer, sensitivity analysis and threshold analysis were performed.

SUBJECTS

All (n = 1931) out born infants with complete transport data admitted to 11 regional tertiary-level Canadian NICUs from January 1996 to October 1997.

MEASURES

Change in Transport Risk Index of Physiologic Stability (TRIPS) Score before and after transport, transport costs.

RESULTS

Change in TRIPS was predicted by gestational age at transport, transport duration, and pretransport TRIPS score, but not the type (EMT, RN, CT) of transport team, mode (air/ground) or direction (forward/retrograde) of transport, presence of a physician, and other baseline population risks (sex, small for gestational age, antenatal corticosteroid treatment, Apgar score). The RN model is least costly under most assumptions. At high transport volumes (>2760 transports per year) and long average transport times (>6.8 h per transport), the EMT model was less costly. Cost drivers of transport were volume of transport, relative wages of transport personnel, and percent of waiting time dedicated to infant transport.

CONCLUSIONS

A deterministic decision-analytic model can be used to model transport cost-effectiveness and derive a threshold analytic chart for identifying the least costly transport model.

Feeding patterns of full-term and preterm infants at forty weeks postconceptional age

Little research exists that addresses the differences in feeding skills between preterm (PT) infants at term and full-term (FT) infants. The purpose of this study was to quantify and examine the differences in sucking abilities of PT infants when measured at 40 weeks postconceptional age (PCA) and newly born FT infants. The sample consisted of 213 infants who were divided into three groups on the basis of their gestational age at birth (24-29 wk, 30-32 wk, and 38-42 wk). The Kron Nutritive Sucking Apparatus (KNSA) was used to examine the microstructure of sucking and feeding behaviors. There were significant differences among the three groups in several of the sucking variables: number of bursts (p = .005), intersuck interval (p = .0212), sucks per burst (p = .0003), suck width (p < .0001), intersuck width (p < .0001), mean maximum pressure (p < .0001), and intersuck width/interburst width (p = .02). The findings from this study demonstrate the importance of both maturation at birth and experience as factors influencing feeding behaviors.

Improving the assessment of gestational age in a Zimbabwean population

OBJECTIVES

To evaluate the performance and the utility of using birthweight-adjusted scores of Dubowitz and Ballard methods of estimating gestational age in a Zimbabwean population.

METHOD

The Dubowitz and the Ballard methods of estimating gestational age were administered to 364 African newborn infants with a known last menstrual period (LMP) at Harare Maternity Hospital.

RESULTS

Both methods were good predictors of gestational age useful in differentiating term from pre-term infants. Our regression line was Y((LMP gestational age))=23.814+0.301*score for the Dubowitz and Y((LMP gestational age))=24.493+0.420*score for the Ballard method. Addition of birthweight to the regression models improved prediction of gestational age; Y((LMP gestational age))=23.512+0.219*score+0.0015*grams for Dubowitz and Y((LMP gestational age))=24.002+0.292*score+0.0016*grams for Ballard method.

CONCLUSIONS

We recommend the use of our birthweight-adjusted maturity scales; the Dubowitz for studies of prematurity, and the Ballard for routine clinical practice.

Sonographic measurements of the liver, spleen and kidney dimensions in the healthy term and preterm newborns

This study was conducted in order to assess normal liver, spleen and kidney dimensions in premature and term newborns and determine the acceptable range. A total of 253 (99 preterm and 154 term) healthy newborns were evaluated within the first week of life by sonography. Gestational age ranged from 24 to 41 weeks, weight ranged from 638 to 4800 g. Measurements were compared with gestational age, weight and height of the infants. Normal ranges for kidney, liver and spleen measurements according to gestational age and weight were obtained. We found that weight showed the best correlation with any one of the mentioned organ dimensions.

Body composition of newborn twins: intrapair differences

OBJECTIVE

To measure body composition in newborn twins and to test the hypothesis that differences in body weights between twins are reflected proportionally by their differences in various components of body composition.

METHODS

48 pairs of newborn twins delivered at a tertiary teaching hospital had dual energy x-ray absorptiometry (DXA) body composition measurement for bone mineral content (BMC), lean and fat mass (LM, FM). Data analyzed with regression and analysis of variance.

RESULTS

Body weight, BMC, LM and FM increased with increased gestational age (p < 0.001). The percent difference in BW between each twin pair was significantly correlated with percent difference in BMC, LM, and FM (p < 0.001). However, mean (+/- SD) percent difference in body weight (14.3+/-10.0%) was significantly lower (p < 0.001) than FM (26.0+/-15.0%) but was not significantly different from LM (13.4+/-9.0%) or BMC (15.9+/-11.6%).

CONCLUSION

In newborn twins, body weight and body composition varies with gestational age. For any twin pair, a difference in body weight was correlated with but not proportional to differences in individual components of body composition.

Thrombopoietin in preterm infants: gestational age-dependent response

PURPOSE

To investigate the factors affecting thrombopoietin (TPO) levels in preterm infants and to determine if TPO levels differ in infants born to mothers with preeclampsia and those infants with culture-proven sepsis.

METHODS

Serial serum samples (N = 95) were obtained from 27 infants less than 33 weeks' gestation. Samples were analyzed for TPO using enzyme-linked immunosorbent assay. All samples had an accompanying complete blood count. Analysis of variance with post hoc analysis by least significant difference test, Mann-Whitney test, or chi2 was used to compare groups, as appropriate. Forward, stepwise linear regression was used to account for potential confounding variables. Data are expressed as mean +/- SD.

RESULTS

TPO levels were not significantly correlated with the absolute platelet counts (R = -0.04, P = 0.69). TPO levels were significantly correlated with gestational age (R= 0.50, P < 0.001) when the platelet count was less than 150,000/mm3. TPO levels were significantly elevated in infants with platelets less than 150,000/mm3 born to mothers with preeclampsia compared with infants with sepsis (1184 +/- 98 vs. 579 +/- 363 pg/mL, P < 0.01). After adjusting for confounding variables using multivariate analysis (model: r2 = 0.43, P < 0.01), gestational age (r2 = 0.26) and preeclampsia (r2 = 0.03) remained significantly associated with TPO levels, whereas sepsis did not contribute to the variability of TPO.

CONCLUSIONS

TPO response of infants with platelets less than 150,000/mm3 is dependent on gestational age. Infants with thrombocytopenia associated with preeclampsia have increased circulating levels of TPO. Infants with thrombocytopenia secondary to sepsis do not show an increase in TPO, but this appears to be an effect of low gestational age.

Comparison of two gentamicin dosing schedules in very low birth weight infants

BACKGROUND

Several dosing schedules for gentamicin have been recommended for very low birth weight infants during the early neonatal period. We conducted a prospective, randomized, controlled trial to compare efficacy and pharmacokinetics of two dosing schedules in preterm neonates.

METHODS

Fifty-eight very low birth weight infants (600 to 1500 g), prescribed gentamicin for treatment of suspected sepsis during the first week after birth, were randomized to receive either the new dosing schedule [every 48 h (q48h)] or the existing dosing schedule [every 24 h (q24h)]. Infants in the "q48h" group received gentamicin at 5.0 or 4.5 mg/kg/dose q48h depending on weight group and infants in the "q24h" group received 2.5 or 3.0 mg/kg/dose q24h. Peak and trough serum gentamicin concentrations were monitored.

RESULTS

Peak serum gentamicin concentrations after the first dose were significantly higher in the q48h infants than in q24h infants (8.19 +/- 1.3 vs. 6.04 +/- 2.2, P = 0.00001). Ninety percent of all peak serum gentamicin concentrations in the q48h group were in a higher therapeutic range of 6 to 12 microg/ml as compared with 55% of q24h (P = 0.0005). None of the q48h infants had subtherapeutic serum gentamicin concentrations immediately after administration of the first dose as compared with 36% of q24h infants (P < 0.005). Eighteen percent of q24h infants continued to have peak serum gentamicin concentrations in subtherapeutic range even after the third dose at 48 h. Trough serum gentamicin concentrations were significantly lower in q48h infants than in q24h infants. However, 9 of 30 (30%) q48h infants had trough serum gentamicin concentrations of < or = 0.5 microg/ml before the dose at 48 h and 4 of the 9 had serum gentamicin concentrations of <1 microg/ml at 24 h after the first dose.

CONCLUSIONS

The q48h dosing schedule of gentamicin given to very low birth weight infants during the first week after birth achieved therapeutic serum gentamicin concentrations and potentially higher peak to MIC ratios for microorganisms in all infants. However, nearly one-third of the infants had extremely low serum gentamicin concentrations before the next dose. A dosing interval of 36 h might be optimal for bactericidal activity and avoid bacterial growth during prolonged periods of extremely low serum gentamicin concentrations; this dosing interval warrants study.

Immunogenicity of hepatitis B vaccine in preterm and full term infants vaccinated within the first week of life

The immunogenicity of a Hepatitis B vaccine was evaluated in 110 neonates (57 full term and 53 preterm) born to Hepatitis B surface antigen (HBsAg) negative mothers. Three 10 microg doses of recombinant Hepatitis B vaccine were administered: the first dose within the first week of life; the second between 1 and 2 months; and the third at 5-7 months of age. Anti-HBs antibody titres were measured 3 months after the third dose. The seroconversion rate in preterm infants (77%; 95% CI=64.7-87.1) was significantly lower than in full term infants (98%; 95% CI=91.6-99.9) while the mean anti-HBs titres among those infants that did seroconvert was lower in preterm (186.6 mIU ml(-1)) than in full term infants (537.5 mIU ml(-1)). More full term than preterm infants showed titres greater than 100 mIU ml(-1) (71.9 and 41.5%, respectively). We conclude that the administration of a recombinant Hepatitis B vaccine shortly after birth is less immunogenic in preterm infants weighing <1800 g at birth than in full term infants. Currently accepted recommendations for post exposure perinatal prophylaxis may be inadequate to protect preterm infants.

Caesarean delivery and outcome in very low birthweight infants

OBJECTIVE

To determine the relationship between mode of delivery, intraventricular haemorrhage (IVH), and mortality in very low birthweight (VLBW) infants.

STUDY DESIGN

A historical cohort study of infants admitted to a single level III neonatal intensive care unit during a five-year period. Infants < 1500 g born by caesarean delivery (n = 400) were compared to those born by vaginal delivery (n = 305).

RESULTS

After controlling for potential confounding variables including: gestational age, fetal presentation, and multiple birth, caesarean delivery was not associated with a decreased odds of IVH (odds ratio 1.2, 95% CI 0.7-2.0), severe IVH (1.9, 0.9-4.0), or mortality (1.2, 0.6-2.4).

CONCLUSIONS

In our population of very low birthweight infants, caesarean delivery is not associated with a decreased risk for mortality or intraventricular haemorrhage.

Growth patterns of extremely low-birth-weight hospitalized preterm infants

OBJECTIVE

To characterize the growth of extremely low-birth-weight (ELBW) infants during hospitalization in terms of weight gain, growth velocity, and relative change in weight.

DESIGN

Retrospective, descriptive design.

SETTING

Two neonatal intensive-care units located in the midwestern United States.

PATIENTS

Thirty-five ELBW infants with a birth weight less than 1,000 g and appropriate for gestational age.

MAIN OUTCOME MEASURES

Clinical data related to the infant's growth and nutrition were obtained from a chart review. Birth weight and discharge weight were compared following conversion of the weights to z scores. The discharge weight was compared to the median weight of a fetus of comparable gestational age based on an intrauterine growth reference. Growth velocity was determined (grams/day).

RESULTS

Weight-for-age z scores decreased significantly between birth and discharge. By discharge, 89% of the infants had discharge weights less than the 10th percentile. The mean discharge weight was significantly less than the median weight of a fetus of comparable gestational age. Days to regain birth weight significantly affected growth outcomes.

CONCLUSION

ELBW infants develop a growth deficit during the first few weeks of life that not only persists but also worsens during hospitalization. Potential causes of this growth deficit include the medical and nutritional management that are part of the usual care of ELBW infants. Because these infants are discharged with this growth deficit, catch-up growth will have to occur at home.

Correlation between plasma and salivary cortisol levels in preterm infants

We sought to determine correlations between plasma and salivary cortisol levels in preterm infants in the basal state and after adrenocorticotropic hormone (ACTH) stimulation during the first week of life. Infants (n = 48) were given ACTH or saline solution; each injection was separated by 24 hours. Salivary and plasma cortisol levels correlated at baseline (r = 0.67, P <.0001) and 1 hour after ACTH stimulation (r = 0.40, P =.0047). ACTH increased cortisol levels in plasma from 12.3 +/- 6.4 to 30.3 +/- 13.2 microg/dL (P <.0001) and in saliva from 1.0 +/- 0.8 to 2.6 +/- 1.0 microg/dL (P <.0001). The adrenal response to ACTH can be detected in the saliva of premature newborns during the first week of life.

Comparison of the prediction of extremely low birth weight neonatal mortality by regression analysis and by neural networks

AIMS

To compare the prediction of mortality in individual extremely low birth weight (ELBW) neonates by regression analysis and by artificial neural networks.

STUDY DESIGN

A database of 23 variables on 810 ELBW neonates admitted to a tertiary care center was divided into training, validation, and test sets. Logistic regression and neural network models were developed on the training set, validated, and outcome (mortality) predicted on the test set. Stepwise regression identified significant variables in the full set. Regression models and neural networks were then tested using data sets with only the identified significant variables, and then with variables excluded one at a time.

RESULTS

The area under the curve (AUC) of receiver operating characteristic (ROC) curves for neural networks and regression was similar (AUC 0.87+/-0.03; p=0.31). Birthweight or gestational age and the 5-min Apgar score contributed most to AUC.

CONCLUSIONS

Both neural networks and regression analysis predicted mortality with reasonable accuracy. For both models, analyzing selected variables was superior to full data set analysis. We speculate neural networks may not be superior to regression when no clear non-linear relationships exist.