Kathleen H Leef

Communicating with parents of premature infants: who is the informant?

Objectives:To determine what sources of information are most helpful for neonatal intensive care unit (NICU) parents, who provides NICU parents with the information, and also what expectations parents have regarding obtaining information.Study design:A 19-item questionnaire was given to the parents of infants 32 weeks or younger prior to discharge from the NICU.Results:Out of the 101 parents who consented, almost all of the parents (96%) felt that ‘the medical team gave them the information they needed about their baby’ and that the ‘neonatologist did a good job of communicating’ with them (91%). However, the nurse was chosen as ‘the person who spent the most time explaining the babys condition, ‘the best source of information,’ and the person who told them ‘about important changes in their babys condition’ (P<0.01).Conclusion:Although the neonatologists role in parent education is satisfactory, the parents identified the nurses as the primary source of information.

Increasing illness severity in very low birth weight infants over a 9-year period

BackgroundRecent reports have documented a leveling-off of survival rates in preterm infants through the 1990s. The objective of this study was to determine temporal changes in illness severity in very low birth weight (VLBW) infants in relationship to the outcomes of death and/or severe IVH.MethodsCohort study of 1414 VLBW infants cared for in a single level III neonatal intensive care unit in Delaware from 1993–2002. Infants were divided into consecutive 3-year cohorts. Illness severity was measured by two objective methods: the Score for Neonatal Acute Physiology (SNAP), based on data from the 1st day of life, and total thyroxine (T4), measured on the 5th day of life. Death before hospital discharge and severe intraventricular hemorrhage (IVH) were investigated in the study sample in relation to illness severity. The fetal death rate was also investigated. Statistical analyses included both univariate and multivariate analysis.ResultsIllness severity, as measured by SNAP and T4, increased steadily over the 9-year study period with an associated increase in severe IVH and the combined outcome of death and/or severe IVH. During the final 3 years of the study, the observed increase in illness severity accounted for 86% (95% CI 57–116%) of the variability in the increase in death and/or severe IVH. The fetal death rate dropped from 7.8/1000 (1993–1996) to 5.3/1000 (1999–2002, p = .01) over the course of the study.ConclusionThese data demonstrate a progressive increase in illness in VLBW infants over time, associated with an increase in death and/or severe IVH. We speculate that the observed decrease in fetal death, and the increase in neonatal illness, mortality and/or severe IVH over time represent a shift of severely compromised patients that now survive the fetal time period and are presented for care in the neonatal unit.

Racial differences in prenatal care of mothers delivering very low birth weight infants.

Objectives:To determine whether there are any racial differences in the prenatal care of mothers delivering very low birth weight infants (VLBW).Study Design:Retrospective cohort study of infants cared for at a single regional level III neonatal intensive care unit over a 9-year period, July 1993–June 2002, N=1234. The main outcome variables investigated included antenatal administration of steroids, delivery by cesarean section, and use of tocolytic medications. Both univariate and multivariate analyses were performed.Results:After controlling for potential confounding variables, white mothers delivering VLBWs had an increased odds of cesarean delivery (odds ratio 1.5, 95% confidence intervals (CI) 1.1–2.0), receiving antenatal steroids (1.3, CI 1.01–1.8), and tocolysis (1.4, CI 1.1–2.0) compared to black mothers. The models controlled for gestational age, multiple gestation, premature labor, clinical chorioamnionitis, maternal age, income, year of birth, and presentation.Conclusions:In our population of VLBWs, white mothers are more likely to receive antenatal steroids, tocolytic medications, and deliver by cesarean section when compared to black mothers. From our data we cannot determine the reasons behind these racial differences in care of mothers delivering VLBWs.

Transfusion volume in infants with very low birth weight: a randomized trial of 10 versus 20 ml/kg.

Background Although preterm infants often require transfusions of red blood cells for anemia of prematurity, the optimal volume of blood to be transfused has not been established. Observations Infants with birth weights between 500 and 1,500 g were randomly assigned to receive 10 or 20 mL/kg red blood cells. Infants with transfusions of 20 mL/kg had a greater hemoglobin (14.2 ± 1.9 vs. 12.0 ± 1.9 g/dL, P = 0. 003) and hematocrit (41.2 ± 5.9 vs. 32.3 ± 7.1%, P = 0.001) levels after transfusion compared with those who received transfusions of 10 mL/kg. There were no measured differences in pulmonary function in either group after transfusion. Conclusions Transfusion with 20 mL/kg red blood cells produces a significantly greater increase in hemoglobin and hematocrit levels than does a transfusion with 10 mL/kg, without any detrimental effects on pulmonary function.

Caesarean delivery and outcome in very low birthweight infants.

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

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.

Thyroid Function in Very-Low-Birth-Weight Infants with Intraventricular Hemorrhage

The objective of this investigation was to study the natural course of thyroid function in infants with intraventricular hemorrhage (IVH). A cohort of infants &lt1,500 grams birth weight, n=247, were included in the analysis. Total T4 and thyrotropin from newborn screening during the 1st week of life (Test 1) and from repeat screening at 2-4 weeks postnatal age (Test 2) were compared in infants with IVH (n=43) and a group of infants without UH. Fifty-nine percent of infants still had transient hypothyroxinemia at the time of Test 2. After multivariate analysis, infants with IVH had an increased odds of having a T4 &le6 μg/dL on Test 1 (OR 2.8, 95% CI 1.2-6.5), but at the time of Test 2 IVH was not associated with an increased odds of having a low T4. Only gestational age (OR 1.6, 95% CI 1.1-2.5) remained associated with an increased odds of having an extremely low T4 (&le4 μg/dL) at this time. Transient hypothyroxinemia remains common at 2-4 weeks of age in preterm infants. IVH is not independently associated with having a low T4 at this time.

Hypothyroxinemia in Mechanically Ventilated Term Infants Is Associated With Increased Use of Rescue Therapies

Objective. Although common in preterm infants, transient hypothyroxinemia (TH) has not been investigated extensively in ill term infants. The objectives of this study were to investigate serum thyroxine (T4) and thyroid-stimulating hormone (TSH) in sick term infants and to determine whether there is any association between measures of thyroid function and short-term outcome in term infants who receive mechanical ventilation. Methods. The investigation consisted of both a prospective observational study and a retrospective cohort study. In the prospective study, T4 and TSH were measured after birth in a group of sick term infants (n = 38) and compared with a group of well term infants (n = 18). Infants in the sick group received mechanical ventilation or continuous positive airway pressure and/or had neonatal seizures. Illness severity was quantified using the Score for Neonatal Acute Physiology. The retrospective cohort study included term infants who required mechanical ventilation and were born over a 5-year period (n = 347). Routine T4 screening was collected on the fifth day of life. TH was diagnosed in infants with a T4 <10%, with a TSH <25 μIU/mL. Clinical outcomes in infants with TH were compared with infants without TH. Results. In the prospective study, infants in the sick group had lower T4 on the fifth day of life as compared with infants in the well group (11.7 ± 4.9 vs 18.9 ± 5.4 μg/dL), and 34% of infants in the sick group had a T4 <10th percentile compared with 6% of infants in the well group. T4 on day of life 5 was inversely correlated with Score for Neonatal Acute Physiology (R = −0.52). In the retrospective study, 21% of mechanically ventilated infants developed TH and were given statistically more inhaled nitric oxide, high-frequency ventilation, vasopressors, and pharmacologic paralysis when compared with infants without TH. Moreover, infants with TH were statistically more likely to die or require transfer to an extracorporeal membrane oxygenation center compared with infants without TH. Conclusion. Our data show that, similar to preterm infants, ill term infants develop TH. Term infants with TH required more intensive rescue interventions, including inhaled nitric oxide and transfer to an extracorporeal membrane oxygenation center. However, whether T4 levels are a marker or a mediator of clinical outcome remains to be determined.

Thyroxine and Illness Severity in Very Low-Birth-Weight Infants

The objective of this study was to determine the relationship between thyroxine (T4) and illness severity in a population of preterm infants. We investigated a cohort of infants with birth weights 1,500 g or less from a single level III neonatal intensive care unit who received a minimum of one cranial sonogram to screen for intraventricular hemorrhage (IVH) and one newborn screen for T4 during a 2-year period, (n = 284). The Score for Neonatal Acute Physiology (SNAP) was used to measure illness severity. T4 and SNAP were investigated in relationship to mortality, IVH, and severe IVH. T4 correlated inversely with SNAP (R = -0.46, p < 0.01). Infants with severe IVH and mortality had lower T4 and higher SNAP scores when compared to infants without these conditions. These differences persisted after controlling for the confounding effect of gestational age. Analysis of receiver operator curves indicated that high SNAP and low T4 were equivalently associated with IVH, severe IVH, and mortality. Our data indicate that T4 is associated with illness severity in very low-birth-weight infants. Low T4 levels and high SNAP scores are both associated with the outcomes of IVH and mortality in very low-birth-weight infants.

Increased leukocytes in infants with intraventricular hemorrhage

The objective of this study was to investigate the relationship between intraventricular hemorrhage (IVH) and cystic periventricular leukomalacia (PVL) with changes in the peripheral blood count. Total peripheral leukocytes, absolute neutrophils, platelets, and nucleated erythrocytes from the first 3 days after birth were compared in very-low-birth-weight infants with (n = 100) and without (n = 388) IVH and cystic PVL (n = 16). After controlling for potential confounding variables, infants with IVH had an increase in total leukocytes and absolute neutrophils and a reduction in nucleated erythrocytes compared with infants without IVH. No difference in any parameters studied was evident with regard to cystic PVL. After controlling for potential confounding variables by logistic regression, infants with a peripheral leukocyte count greater than 25,000/mm(3) beyond 24 hours of age had an odds ratio of 2.1 (95% confidence interval = 1.1-4.3) for developing IVH. We conclude that IVH is associated with an increase in total leukocytes and absolute neutrophils for 72 hours after birth in very-low-birth-weight infants. Further investigation is required to determine whether this leukocytosis is important in the pathophysiology of brain injury or is an associated factor.