Abstracts "Pediatrics"
Junio 2007
Abstract 1 de 11
OBJECTIVES. The purpose of this work was to compare the efficacy of propofol, a hypnotic agent, to the regimen of morphine, atropine, and suxamethonium as an induction agent for nonemergency neonatal endotracheal intubation. We hypothesized that propofol aids intubation by allowing the continuation of spontaneous breathing.
PATIENTS AND METHODS. We conducted a randomized, open-label, controlled trial of infants who required nonemergency endotracheal intubation. Primary outcome was successful intubation confirmed by chest auscultation and clinical examination of the infant.
RESULTS. Infants randomly assigned to propofol (n = 33) and the morphine, atropine, and suxamethonium regimen (n = 30) were comparable in median gestational age (27 vs 28 weeks), birth weight (1020 vs 1095 g), weight at intubation (1068 vs 1275 g), and age at intubation (4 vs 3 days). Sleep or muscle relaxation were achieved within 60 seconds in both groups, but time to achieve successful intubation was more than twice as fast with propofol (120 vs 260 seconds). Blood pressure and heart rates were not different, but intraprocedural oxygen saturations were significantly lower in infants on the morphine, atropine, and suxamethonium regimen (trough arterial oxygen saturation: 60% vs 80%). Nasal/oral trauma was less common, and recovery time was shorter (780 vs 1425 seconds) in the propofol group. No significant adverse effects were seen in either group.
CONCLUSIONS. Propofol is more effective than the morphine, atropine, and suxamethonium regimen as an induction agent to facilitate neonatal nasal endotracheal intubation. Importantly, hypoxemia was less severe, probably because of the maintenance of spontaneous breathing. A controlled environment may have promoted the ease of intubation, resulting in less trauma. The shorter duration of action would be advantageous in a compromised infant.
Abstract 2 de 11
OBJECTIVE. A physiologic predisposition toward hypertension is theorized to result from the combination of intrauterine growth restriction followed by rapid catch-up growth. The objective of this study was to evaluate the effects of birth weight and weight gain during childhood on the risk for high blood pressure in childhood and to identify discrete periods of catch-up growth that put children with intrauterine growth restriction at increased risk for the development of high blood pressure later in life.
METHODS. The US Collaborative Perinatal Project (1959–1974) studied 55908 pregnancies in an observational cohort at 12 medical centers in the United States and followed the offspring through 7 years of age. All white or black children who were born at term and completed the follow-up without kidney or heart disease were included in this posthoc analysis. z scores were calculated for weight at birth, 4 months, 1 year, 4 years, and 7 years on the basis of study means and SD. Changes in z scores were calculated for each interval.
RESULTS. Each 1-kg increase in birth weight increased the odds for high systolic blood pressure by 2.19 and high diastolic blood pressure by 1.82 when race and change in weight z scores were also included in the regression model. An increase in weight z score of 1 SD above the previous weight z score increased the odds for high systolic blood pressure at 7 years by 1.65 (birth to 4 months), 1.79 (4 months to 1 year), 1.71 (1–4 years), and 1.94 (4–7 years) in the full model. White race increased the odds for high systolic blood pressure by 1.51.
CONCLUSIONS. In this large biracial US cohort, infants who were small for gestational age were not at increased risk for high blood pressure at 7 years of age. However, children who crossed weight percentiles upward during early childhood did demonstrate an increased risk.
Abstract 3 de 11
OBJECTIVE. The objective of this study was to investigate possible alterations in circulating levels of the adipocytokine visfatin in intrauterine growth-restricted and normal pregnancies, given that these groups differ considerably in fetal nutrition, body fat mass, and metabolic/endocrine mechanisms.
METHODS. Serum visfatin levels were prospectively
measured by enzyme immunoassay in 40 mothers and their 40 singleton
term fetuses and neonates on postnatal days 1 and 4. Twenty neonates
had intrauterine growth restriction (birth weight
3rd
customized centile, adjusted for parameters that influence growth
potential), and 20 were appropriate for gestational age.
RESULTS. Circulating maternal visfatin levels were significantly elevated in pregnancies with intrauterine growth restriction compared with control pregnancies with appropriate-for-gestational-age infants and negatively correlated with customized centiles in the group with intrauterine growth restriction. Postnatal day-1 and -4 visfatin levels were significantly higher in neonates with intrauterine growth restriction compared with neonates who were appropriate for gestational age. Postnatal-day-1 prefeeding insulin levels were significantly lower in neonates with intrauterine growth restriction.
CONCLUSIONS. Pathologic conditions in pregnancy that lead to intrauterine growth restriction could be responsible for elevated maternal visfatin levels. Higher visfatin levels in neonates with intrauterine growth restriction may serve as an early marker with prognostic value for later development of insulin resistance or type 2 diabetes, whereas lower insulin levels may indicate reduced ß-cell mass and/or impaired ß-cell function.
Abstract 4 de 11
OBJECTIVE. We have demonstrated earlier an accelerated maturation of the visual evoked potential in the first year of life in preterm infants with antenatal brain sparing. We have now assessed visual functioning at 11 years of age in the same cohort and compared the groups with and without brain sparing.
DESIGN/METHODS. One hundred sixteen survivors included in a study on the outcome of preterm infants born at <33 weeks' gestation with and without fetal brain sparing and admitted to the NICU were followed extensively. Ninety-eight infants (85%) were again assessed at 11 years of age. Data were available for fetal Doppler measurements indicating brain sparing, neonatal cerebral ultrasound scanning, and developmental outcome in the first 5 years. Mean birth weight was 1303 g; mean gestational age was 29.8 weeks. The infants were divided into 2 groups with and without brain sparing. Visual functioning was estimated by measuring visual acuity, visual fields, eye position, and binocular function and by visual motor tests.
RESULTS. Six percent of the children were found to have a visual acuity of <0.8, 12% had strabismus, and 14% to 46% showed abnormal results on the visual motor tests. No statistical differences were found between the 2 groups. However, children with severe cerebral ultrasound diagnoses in the neonatal period were found to have significantly more abnormalities on visual functioning and lower scores on visual motor tests than children without these morbidities.
CONCLUSIONS. Children with fetal brain sparing do not demonstrate a different development of their visual functioning at late school age. However, an abnormal cerebral ultrasound in the neonatal period is associated with impaired visual function in later life.
Abstract 5 de 11
OBJECTIVES. Craniosynostosis is a devastating disorder characterized by premature closure of the cranial plates before or shortly after birth. This results in an abnormally shaped skull, face, and brain. Little is known about hearing disorders in such patients, and nothing has been published about their auditory brainstem responses. Our objective was to evaluate such patients for auditory brainstem response and hearing disorders with the long-term goal of improving patient evaluation and management.
PATIENTS AND METHODS. We evaluated the auditory brainstem responses, hearing, and brain images of children with fibroblast growth factor receptor 2 craniosynostosis (n = 11).
RESULTS. Prolongation of the auditory brainstem response I-to-III interpeak latency was a frequent characteristic of fibroblast growth factor receptor 2 craniosynostosis, occurring in 91% of our patients. Prolongation of the III-to-V interpeak latency was an occasional characteristic, occurring in 27% of our patients. Whenever the I-to-III interpeak latency was prolonged, wave II was always abnormal. Associated morbidities included sensorineural hearing loss (27%), recurrent otitis media (100%), and Arnold-Chiari malformation (27%). Cranial decompression improved the interpeak latencies of 2 children.
CONCLUSIONS. These previously undocumented auditory brainstem response abnormalities reflect abnormal neural transmission, which could cause peripheral and central auditory processing disorders. We speculate that the major pathogenic basis of the I-to-III interpeak latency and wave II abnormalities is compression of the auditory nerve as it passes through the internal auditory meatus and posterior fossa, which would explain the auditory nerve hearing loss, tinnitus, and vertigo that affect these children. Awareness of these abnormalities could lead to important advancements in the auditory and neurosurgical assessment and management of this overlooked patient group. We provide recommendations for the improved assessment and management of these patients. In particular, we recommend that auditory brainstem response diagnostics become standard clinical care for this patient group as the best way to detect auditory nerve compression.
Abstract 6 de 11
BACKGROUND. The benefits of exogenous surfactants for prevention or treatment of respiratory distress syndrome are well established, but there is a paucity of long-term follow-up data from surfactant-comparison trials.
OBJECTIVE. We sought to determine and compare survival and pulmonary and neurodevelopmental outcomes through 1 year corrected age of preterm infants who received lucinactant and other surfactants in the SELECT (Safety and Effectiveness of Lucinactant Versus Exosurf in a Clinical Trial) and STAR (Surfaxin Therapy Against Respiratory Distress Syndrome) trials individually and, secondarily, from analysis using combined data from these 2 trials.
METHODS. All infants from both trials who were randomly assigned to administration of lucinactant (175 mg/kg), colfosceril palmitate (67.5 mg/kg), beractant (100 mg/kg), or poractant alfa (175 mg/kg) were prospectively followed through 1 year corrected age, at which point masked assessment of outcomes was performed for surviving infants. One-year survival was a key outcome of interest. Other parameters assessed included rates of rehospitalization and respiratory morbidity and gross neurologic status. Data were analyzed by comparing the different surfactants within each trial and, in secondary analysis, combining data from both trials to compare lucinactant versus the animal-derived surfactants (beractant and poractant) used in these trials. Survival rates over time were compared by using the Wilcoxon test for survival through 1 year corrected age and logistic regression for comparison of fixed time points. The latter analyses were performed by using the prespecified approach, where loss to follow-up or withdrawal of consent was imputed as a death, and also using raw data. Other outcomes were analyzed by using the Cochran-Mantel-Haenszel test or logistic regression for categorical data, and analysis of variance on ranks was used for continuous data.
RESULTS. Very few cases were lost to follow-up in either trial (29 of 1546 enrolled in both trials [1.9%]). In the primary analysis of the SELECT trial comparing lucinactant to either colfosceril or beractant, there were no significant differences in the proportion of infants who were alive through 1 year corrected age. Fixed-time-point estimates of mortality at 1 year corrected age imputing loss to follow-up as a death were 28.1% for lucinactant, 31.0% for colfosceril, and 31.0% for beractant. By using raw data without imputing loss to follow-up as a death, mortality estimates at 1 year corrected age were computed to be 26.6%, 29.1%, and 28.3%, respectively. In the primary analysis of the STAR trial, significantly more infants treated with lucinactant were alive through 1 year corrected age compared with those who received poractant alfa. Fixed time estimates of mortality at 1 year corrected age imputing loss to follow-up as a death were 19.4% for lucinactant and 24.2% for poractant. These estimates using raw data that did not impute loss to follow-up as a death were 18.6% and 21.9%, respectively. In the combined analysis, survival through 1 year corrected age was higher for infants in the lucinactant group versus that of the infants in the animal-derived surfactants (beractant and poractant) group. The fixed-time-point estimates of mortality at 1 year corrected age imputing loss to follow-up as a death for lucinactant and animal-derived surfactants were 26.0% and 29.4%, respectively. However, the 1-year-corrected-age estimates using combined raw data were 24.6% for the lucinactant group and 26.7% for the animal-derived surfactant group. The incidence of postdischarge rehospitalizations, total number of rehospitalizations, incidence of respiratory illnesses, and total number of respiratory illnesses were generally similar among those in the treatment groups. Neurologic status at 1 year corrected age was essentially similar between infants who received lucinactant and those who received all other surfactants used in these 2 trials.
CONCLUSIONS. Findings from this 1-year follow-up of both lucinactant trials indicate that this new peptide-based synthetic surfactant is at least as good, if not superior, to animal-derived surfactants for prevention of respiratory distress syndrome and may be a viable alternative to animal-derived products.
Abstract 7 de 11
OBJECTIVE. The objective of this study was to determine the rate of compliance with hospital guidelines for alarm limits for pulse oximetry in preterm infants on oxygen therapy.
METHODS. All infants admitted to the nurseries at the Royal Women's Hospital, Melbourne, Australia, with gestational age <32 weeks or birth weight <1500 g between August 2005 and February 2006 were eligible for inclusion. Data on the alarm limits set for infants on oxygen therapy were collected prospectively. The target saturation range recommended in written hospital guidelines was 88% to 92%, with alarm limits set at 85% and 94%.
RESULTS. Data were prospectively collected for 144 subjects with mean (SD) gestational age 29.3 (2.4) weeks and birth weight 1226 (354) g; 1073 alarm limits were collected when infants were on oxygen. The lower alarm limit was set correctly 91.1% of the time. In contrast, the upper alarm limit was set correctly only 23.3% of the time: 76.5% of the time it was too high, and 23.8% of the time it was set at 100%. Infants with an upper alarm limit set correctly on a particular day had a significantly lower birth weight, gestational age, postmenstrual age, and postnatal age than infants who had the upper alarm limit set too high. Use of assisted ventilation, higher inspired oxygen concentrations, and more frequent changes in inspired oxygen concentration were all associated with improved odds of having an appropriately set upper alarm limit.
CONCLUSIONS. This study suggests that current guidelines regarding the upper pulse oximeter alarm limit for infants receiving oxygen might be commonly exceeded, although compliance might be better for infants at higher risk of adverse outcomes. However, there might be less variation from guidelines for the lower alarm limit.
Abstract 8 de 11
OBJECTIVES. In August 2005, the Centers for Disease Control and Prevention was notified of a Ralstonia species outbreak among pediatric patients receiving supplemental oxygen therapy with the Vapotherm 2000i (Vapotherm, Inc, Stevensville, MD). The Vapotherm 2000i is a reusable medical device that was used in >900 hospitals in the United States in 2005. Ralstonia are waterborne bacilli that have been implicated in hospital-acquired infections. We initiated an investigation to determine the source of the outbreak and implement infection control and prevention measures.
PATIENTS AND METHODS. We performed a case-control study at 1 hospital and conducted national case findings to obtain clinical and environmental samples for laboratory analysis. Case-patients had health care–acquired Ralstonia colonization or infection. Isolates were compared by using pulsed-field gel electrophoresis. We tested manufacturer-recommended disinfection protocols for the Vapotherm 2000i under simulated-use conditions.
RESULTS. Case-patients at the hospital (n = 5) were more likely to have received Vapotherm therapy than controls. Nationally, Ralstonia mannitolilytica was confirmed in 38 patients (aged 5 days to 7 years); 35 (92%) of the patients were exposed to the Vapotherm 2000i before recovery of the organism. Pulsed-field gel electrophoresis showed related R mannitolilytica strains from isolates sent from 18 hospitals in 12 states. A Vapotherm machine reprocessed with a protocol proposed by the manufacturer grew Ralstonia spp after 7 days of simulated use. In December 2005, Vapotherm recalled the 2000i.
CONCLUSIONS. Our findings suggest intrinsic contamination of Vapotherm devices with Ralstonia spp. New medical devices may provide therapy equivalent to current devices yet pose novel reprocessing challenges.
Abstract 9 de 11
OBJECTIVE. Low maternal folate levels during pregnancy correlate with low birth weight, a perinatal risk factor for later cardiovascular disease. We studied relationships between red blood cell folate levels, birth weight, and vascular endothelial function (a key factor in the early pathophysiologic processes of heart disease) in newborn infants.
METHODS. We included 82 infants (30 low birth weight) and their mothers. A laser Doppler technique was used to measure skin perfusion during transdermal iontophoresis of acetylcholine (an endothelium-dependent vasodilator). Red blood cell folate, vitamin B12, and homocysteine levels were determined.
RESULTS. The perfusion response to acetylcholine was lower in low birth weight infants than in normal birth weight control subjects (mean: 35 vs 76 perfusion units). The neonatal acetylcholine response correlated with red blood cell folate levels in both infants and their mothers. The folate levels of low birth weight and control infants did not differ significantly (mean: 1603 vs 1795 nmol/L), but mothers of low birth weight infants had lower folate levels than did mothers of control infants (mean: 805 vs 1109 nmol/L). In multivariate analysis, low birth weight and red blood cell folate levels contributed independently to endothelial function in newborn infants. The levels of vitamin B12 and homocysteine were similar in the 2 groups and did not correlate with endothelial function.
CONCLUSION. The data presented here provide the first evidence for a relationship between folate levels and vascular endothelial function in newborn infants.
Abstract 10 de 11
OBJECTIVE. The aim was to determine whether inhaled nitric oxide therapy improves neurodevelopmental outcomes for infants with preterm persistent pulmonary hypertension of the newborn.
METHODS. We conducted a historical cohort study to compare the 3-year incidence of cerebral palsy in preterm singleton infants (<34 gestational weeks) with hypoxemic respiratory failure caused by persistent pulmonary hypertension of the newborn who received inhaled nitric oxide (16 patients) or 100% oxygen (15 patients) therapy. All neonates had clinical and echocardiographic evidence of pulmonary hypertension without structural heart disease.
RESULTS. The incidence of cerebral palsy among patients
treated with inhaled nitric oxide was 12.5%, whereas that among
patients treated with 100% oxygen was 46.7%. After adjustment for
maternal fever (
38°C)
during delivery, birth weight, Apgar score at 5 minutes, high-frequency
oscillatory ventilation, and surfactant therapy, inhaled nitric oxide
therapy, compared with 100% oxygen therapy, was associated with a
decreased risk of cerebral palsy in preterm infants with persistent
pulmonary hypertension of the newborn.
CONCLUSION. Inhaled nitric oxide therapy decreases the risk of cerebral palsy in preterm infants with persistent pulmonary hypertension of the newborn.
Abstract 11 de 11
OBJECTIVES. The purpose of this work was to determine whether the reported association between neonatal morbidities and a patent ductus arteriosus is because of the left-to-right patent ductus arteriosus shunt itself, the therapies used to treat it, or the immaturity of the infants who are likely to develop a patent ductus arteriosus.
METHODS. A total of 446 infants (<28 weeks' gestation) were treated with the same patent ductus arteriosus care–oriented protocol, and logistic regression analysis was used to examine the effects of several patent ductus arteriosus–related variables (presence of a symptomatic patent ductus arteriosus, the number of indomethacin doses used, the ductus response to indomethacin, and the use of surgical ligation) on the incidence of retinopathy of prematurity, necrotizing enterocolitis, chronic lung disease, death, and neurodevelopmental impairment.
RESULTS. Most of the predictive effects that the presence of a patent ductus arteriosus and its treatment had on neonatal morbidity could be accounted for by the infants' immature gestation. Use of surgical ligation, however, was significantly associated with the development of chronic lung disease and was independent of immature gestation, other patent ductus arteriosus–related variables, or other perinatal and neonatal risk factors known to be associated with chronic lung disease.
CONCLUSIONS. These findings add to the growing uncertainty about the benefits and risks of surgical ligation during the neonatal period.