Lu-Ann Papile

INCIDENCE AND EVOLUTION OF SUBEPENDYMAL AND INTRAVENTRICULAR HEMORRHAGE: A STUDY OF INFANTS WITH BIRTH WEIGHTS LESS THAN 1,500 GM

We have performed brain scanning by computed tomography on 46 consecutive live-born infants whose birth weights were less than 1,500 gm; 20 of them had evidence of cerebral intraventricular hemorrhage. Nine of the 29 infants who survived had IVH. Four grades of IVH were identified. Grade I and II lesions resolved spontaneously, but there was prominence of the interhemispheric fissue on CT of the infants at six months of age. Hydrocephalus developed in infants with Grade III and IV lesions. Seven of the surviving infants with IVH did not have clinical evidence of hemorrhage. There were no significant differences between the infants with and without IVH in birth weight, gestational age, one- and five-minute Apgar scores, or the need for resuscitation at birth or for subsequent respiratory assistance.

Relationship of cerebral intraventricular hemorrhage and early childhood neurologic handicaps

The outcome in 198 surviving very-low-birth-weight (less than 1501 gm) infants with and without cerebral intraventricular hemorrhage was compared to determine whether CVH is associated with early childhood developmental or neuromotor handicaps. Major handicaps were noted in 10% of the infants without and 28% of the infants with CVH. Among the infants with CVH, a major handicap was present in 9% with grade 1, 11% with grade 2, 36% with grade 3, and 76% with grade 4 CVH. Infants with posthemorrhagic hydrocephalus had the same incidence of major handicaps (59%) as did comparable infants with no hydrocephalus (57%). Our data indicate that grades 1 and 2 CVH do not increase an infants risk for major handicaps, and there is a direct relationship of grades 3 and 4 CVH and major handicaps.

Sex differences in outcomes of very low birthweight infants: the newborn male disadvantage

OBJECTIVE To determine the differences in short term outcome of very low birthweight infants attributable to sex. METHODS Boys and girls weighing 501–1500 g admitted to the 12 centres of the National Institute of Child Health and Human Development Neonatal Research Network were compared. Maternal information and perinatal data were collected from hospital records. Infant outcome was recorded at discharge, at 120 days of age if the infant was still in hospital, or at death. Best obstetric estimate based on the last menstrual period, standard obstetric factors, and ultrasound were used to assign gestational age in completed weeks. Data were collected on a cohort that included 3356 boys and 3382 girls, representing all inborn births from 1 May 1991 to 31 December 1993. RESULTS Mortality for boys was 22% and that for girls 15%. The prenatal and perinatal data indicate few differences between the sex groups, except that boys were less likely to have been exposed to antenatal steroids (odds ratio (OR) = 0.80) and were less stable after birth, as reflected in a higher percentage with lower Apgar scores at one and five minutes and the need for physical and pharmacological assistance. In particular, boys were more likely to have been intubated (OR = 1.16) and to have received resuscitation medication (OR = 1.40). Boys had a higher risk (OR > 1.00) for most adverse neonatal outcomes. Although pulmonary morbidity predominated, intracranial haemorrhage and urinary tract infection were also more common. CONCLUSIONS Relative differences in short term morbidity and mortality persist between the sexes.

Levels of Neonatal Care

Provision of risk-appropriate care for newborn infants and mothers was first proposed in 1976. This updated policy statement provides a review of data supporting evidence for a tiered provision of care and reaffirms the need for uniform, nationally applicable definitions and consistent standards of service for public health to improve neonatal outcomes. Facilities that provide hospital care for newborn infants should be classified on the basis of functional capabilities, and these facilities should be organized within a regionalized system of perinatal care.

Autoregulation of Cerebral Blood Flow in the Preterm Fetal Lamb

ABSTRACT: The purpose of the present study was to determine if autoregulation of cerebral blood flow (CBF) is present in the preterm fetal lamb and, if present, to measure the range of mean arterial blood pressure over which autoregulation exists. Thirty-seven measurements of CBF were made in seven preterm fetal lambs (118–122 days gestation) over a mean carotid arterial blood pressure (CBP) range of 18–90 mm Hg. CBF was measured by the radionuclide-labeled microsphere technique. CBP was altered by graduated inflation of balloons placed around the brachiocephalic trunk and the aortic isthmus. To eliminate the effects of reflex changes in heart rate, the carotid sinus and aortic nerve were ablated bilaterally. CBF was linearly related to mean CBP from 18–45 mm Hg, constant over a mean CBP of 45–80 mm Hg, and again linear from 80–90 mm Hg. Resting mean CBP (normotension) was 53.8 ± 1.9 mm Hg during the control period and 51.7 ± 0.8 mm Hg during the equillibration periods. This study demonstrates that although autoregulation of CBF is intact in the preterm fetal lamb, the range is narrowed compared to the term lamb and resting mean CBP lies close to the lower limit of autoregulation.

Relationship of intravenous sodium bicarbonate infusions and cerebral intraventricular hemorrhage

The incidence of cerebral intraventricular hemorrhage was determined by computed tomography in 100 infants with birth weights less than or equal to 1,500 gm. A comparison of IVH with serum sodium concentrations and the amount of intravenous sodium bicarbonate administered did not reveal a significant relationship. Analysis of the method of infusion of sodium bicarbonate indicated that the rapid infusion of hyperosmolar (M to M/12) sodium bicarbonate is associated with a significantly increased incidence of IVH.

Hypothermia and neonatal encephalopathy.

Data from large randomized clinical trials indicate that therapeutic hypothermia, using either selective head cooling or systemic cooling, is an effective therapy for neonatal encephalopathy. Infants selected for cooling must meet the criteria outlined in published clinical trials. The implementation of cooling needs to be performed at centers that have the capability to manage medically complex infants. Because the majority of infants who have neonatal encephalopathy are born at community hospitals, centers that perform cooling should work with their referring hospitals to implement education programs focused on increasing the awareness and identification of infants at risk for encephalopathy, and the initial clinical management of affected infants.

Dexamethasone therapy increases infection in very low birth weight infants.

Background. Infection is a major complication of preterm infants, resulting in increased morbidity and mortality. We recently reported the results of a multicenter trial of dexamethasone initiated at 14 or 28 days in very low birth weight (VLBW) infants who were at risk for chronic lung disease; the results showed an increase in nosocomial bacteremia in the group receiving dexamethasone. This study is an in-depth analysis of bacteremia/sepsis and meningitis among infants enrolled in the trial. Methods. Data on cultures performed and antibiotic therapy were collected prospectively. Infections were classified as definite or possible/clinical. Results. A total of 371 infants were enrolled in the trial. There were no baseline differences in risk factors for infection. For the first 14 days of study, infants received either dexamethasone (group I, 182) or placebo (group II, 189). During this period, infants in group I were significantly more likely than those in group II to have a positive blood culture result (48% vs 30%) and definite bacteremia/sepsis/meningitis (22% vs 14%). Over the 6-week study period, 47% of those cultured had at least one positive blood culture result (53% in group I vs 41% in group II) and 25% of the infants had at least one episode of definite bacteremia/sepsis/meningitis (29% in group I vs 21% in group II). Among infants with definite infections, 46.8% were attributable to Gram-positive organisms, 26.6% to Gram-negative organisms and 26.6% to fungi. The factors present at randomization were evaluated for their association with infection. Group I assignment and H2blocker therapy (before study entry) were associated with increased risk of definite infection, whereas cesarean section delivery and increasing birth weight were associated with decreased risk. Conclusions. Infants who received a 14-day course of dexamethasone initiated at 2 weeks of age were more likely to develop a bloodstream or cerebrospinal fluid infection while on dexamethasone therapy than were those who received placebo. Physicians must consider this increased risk of infection when deciding whether to treat VLBW infants with dexamethasone.

Posthemorrhagic hydrocephalus in low-birth-weight infants: Treatment by serial lumbar punctures

We have performed weekly computed tomographic brain scans on 28 surviving low-birth-weight infants with cerebral intraventricular hemorrhage and acute ventricular dilatation. Evolving hydrocephalus was observed in 15 infants. Twelve of the 15 infants were treated by removing large volumes of cerebrospinal fluid with serial lumbar punctures. Arrest in the progression of hydrocephalus was evident in 11 of the 12. Clinical hydrocephalus requiring surgical intervention occurred in one of the treated infants and in all three untreated infants. No complications of serial lumbar punctures were noted, whereas shunt-related morbidity was 100%. Our results suggest that serial lumbar punctures are effective in arresting the development of posthemorrhagic hydrocephalus.

Respiratory support in preterm infants at birth.

Current practice guidelines recommend administration of surfactant at or soon after birth in preterm infants with respiratory distress syndrome. However, recent multicenter randomized controlled trials indicate that early use of continuous positive airway pressure with subsequent selective surfactant administration in extremely preterm infants results in lower rates of bronchopulmonary dysplasia/death when compared with treatment with prophylactic or early surfactant therapy. Continuous positive airway pressure started at or soon after birth with subsequent selective surfactant administration may be considered as an alternative to routine intubation with prophylactic or early surfactant administration in preterm infants.