Association of Mothers' Perception of Neighborhood Quality and Maternal Resilience with Risk of Preterm Birth.

We examined the associations of mothers' perception of neighborhood quality and maternal resilience with risk of preterm birth and whether maternal resilience moderated the effect of neighborhood quality perception. We analyzed data from 10,758 women with singleton births who participated in 2010-2012 Los Angeles Mommy and Baby surveys. Multilevel logistic regression models assessed the effects of mothers' perception of neighborhood quality and maternal resilience on preterm birth (yes/no), controlling for potential confounders and economic hardship index, a city-level measure of neighborhood quality. Interaction terms were assessed for moderation. Mothers' perception of neighborhood quality and maternal resilience were each uniquely associated with preterm birth, independent of potential confounders (p-values < 0.05). The risk of preterm birth among mothers who perceived their neighborhood as of poor quality was about 30% greater compared to mothers who perceived their neighborhood as of good quality; the risk was 12% greater among mothers with low resilience compared to those with high resilience. Effects of neighborhood quality were not modified by maternal resilience. The findings suggest that mothers' perception of neighborhood quality and resilience are associated with the risk of preterm birth. Further research should explore whether initiatives aimed at improving neighborhood quality and women's self-esteem may improve birth outcomes

Tracheal suctioning improves gas exchange but not hemodynamics in asphyxiated lambs with meconium aspiration.

BackgroundCurrent neonatal resuscitation guidelines recommend tracheal suctioning of nonvigorous neonates born through meconium-stained amniotic fluid.MethodsWe evaluated the effect of tracheal suctioning at birth in 29 lambs with asphyxia induced by cord occlusion and meconium aspiration during gasping.ResultsTracheal suctioning at birth (n = 15) decreased amount of meconium in distal airways (53 ± 29 particles/mm(2) lung area) compared to no suction (499 ± 109 particles/mm(2); n = 14; P < 0.001). Three lambs in the suction group had cardiac arrest during suctioning, requiring chest compressions and epinephrine. Onset of ventilation was delayed in the suction group (146 ± 11 vs. 47 ± 3 s in no-suction group; P = 0.005). There was no difference in pulmonary blood flow, carotid blood flow, and pulmonary or systemic blood pressure between the two groups. Left atrial pressure was significantly higher in the suction group. Tracheal suctioning resulted in higher Pao2/FiO2 levels (122 ± 21 vs. 78 ± 10 mm Hg) and ventilator efficiency index (0.3 ± 0.05 vs.0.16 ± 0.03). Two lambs in the no-suction group required inhaled nitric oxide. Lung 3-nitrotyrosine levels were higher in the suction group (0.65 ± 0.03 ng/µg protein) compared with the no-suction group (0.47 ± 0.06).ConclusionTracheal suctioning improves oxygenation and ventilation. Suctioning does not improve pulmonary/systemic hemodynamics or oxidative stress in an ovine model of acute meconium aspiration with asphyxia

Sustained inflation at birth did not alter lung injury from mechanical ventilation in surfactant-treated fetal lambs.

BackgroundSustained inflations (SI) are used with the initiation of ventilation at birth to rapidly recruit functional residual capacity and may decrease lung injury and the need for mechanical ventilation in preterm infants. However, a 20 second SI in surfactant-deficient preterm lambs caused an acute phase injury response without decreasing lung injury from subsequent mechanical ventilation.HypothesisA 20 second SI at birth will decrease lung injury from mechanical ventilation in surfactant-treated preterm fetal lambs.MethodsThe head and chest of fetal sheep at 126±1 day GA were exteriorized, with tracheostomy and removal of fetal lung fluid prior to treatment with surfactant (300 mg in 15 ml saline). Fetal lambs were randomized to one of four 15 minute interventions: 1) PEEP 8 cmH2O; 2) 20 sec SI at 40 cmH2O, then PEEP 8 cmH2O; 3) mechanical ventilation with 7 ml/kg tidal volume; or 4) 20 sec SI then mechanical ventilation at 7 ml/kg. Fetal lambs remained on placental support for the intervention and for 30 min after the intervention.ResultsSI recruited a mean volume of 6.8±0.8 mL/kg. SI did not alter respiratory physiology during mechanical ventilation. Heat shock protein (HSP) 70, HSP60, and total protein in lung fluid similarly increased in both ventilation groups. Modest pro-inflammatory cytokine and acute phase responses, with or without SI, were similar with ventilation. SI alone did not increase markers of injury.ConclusionIn surfactant treated fetal lambs, a 20 sec SI did not alter ventilation physiology or markers of lung injury from mechanical ventilation

Inhaled nitric oxide as an adjunct to neonatal resuscitation in premature infants: a pilot, double blind, randomized controlled trial.

BackgroundNitric oxide (NO) plays an important role in normal postnatal transition. Our aims were to determine whether adding inhaled NO (iNO) decreases supplemental oxygen exposure in preterm infants requiring positive pressure ventilation (PPV) during resuscitation and to study iNO effects on heart rate (HR), oxygen saturation (SpO2), and need for intubation during the first 20 min of life.MethodsThis was a pilot, double-blind, randomized, placebo-controlled trial. Infants 25 0/7-31 6/7 weeks' gestational age requiring PPV with supplemental oxygen during resuscitation were enrolled. PPV was initiated with either oxygen (FiO2-0.30) + iNO at 20 ppm (iNO group) or oxygen (FiO2-0.30) + nitrogen (placebo group). Oxygen was titrated targeting defined SpO2 per current guidelines. After 10 min, iNO/nitrogen was weaned stepwise per protocol and terminated at 17 min.ResultsTwenty-eight infants were studied (14 per group). The mean gestational age in both groups was similar. Cumulative FiO2 and rate of exposure to high FiO2 (>0.60) were significantly lower in the iNO group. There were no differences in HR, SpO2, and need for intubation.ConclusionsAdministration of iNO as an adjunct during neonatal resuscitation is feasible without side effects. It diminishes exposure to high levels of supplemental oxygen

Prenatal Corticosteroids for Reducing Morbidity and mortality after Preterm Birth

Annotated and edited transcript of a Witness Seminar held on 15 June 2004. Introduction by Barbara Stocking, Oxfam. First published by the Wellcome Trust Centre for the History of Medicine at UCL, 2005.©The Trustee of the Wellcome Trust, London, 2005.All volumes are freely available online at: www.history.qmul.ac.uk/research/modbiomed/wellcome_witnesses/Annotated and edited transcript of a Witness Seminar held on 15 June 2004. Introduction by Barbara Stocking, Oxfam.Annotated and edited transcript of a Witness Seminar held on 15 June 2004. Introduction by Barbara Stocking, Oxfam.Annotated and edited transcript of a Witness Seminar held on 15 June 2004. Introduction by Barbara Stocking, Oxfam.Annotated and edited transcript of a Witness Seminar held on 15 June 2004. Introduction by Barbara Stocking, Oxfam.Annotated and edited transcript of a Witness Seminar held on 15 June 2004. Introduction by Barbara Stocking, Oxfam.Annotated and edited transcript of a Witness Seminar held on 15 June 2004. Introduction by Barbara Stocking, Oxfam.In 1959 the New Zealand obstetrician Graham (Mont) Liggins began investigating mechanisms that triggered premature labour. Supported by the Wellcome Trust, he examined the effects of hormones on labour in sheep, and demonstrated coincidentally that in utero corticosteroids accelerated fetal lung maturation. A randomized controlled trial (RCT) of prenatal corticosteroids in humans by Liggins and pediatrician Ross Howie, showed a reduction of respiratory distress syndrome in preterm babies. This Witness Seminar, chaired by the late Dr Edmund Hey, discussed the influence of Liggins' and Howie's 1972 paper announcing these results, and subsequent work by Avery and Kotas on induction of pulmonary surfactant in lambs. Other subjects included Crowley's 1981 systematic review of four RCTs; the low uptake of corticosteroids in practice until the Royal College of Obstetricians and Gynaecologists issued usage guidelines in 1992; trials to determine optimum drug, dose and number of courses; potential adverse effects; and cost-benefit analysis. Participants included the late Dr Mel Avery, Sir Iain Chalmers, Dr Patricia Crowley, the late Professor Harold Gamsu, Professor Jane Harding, Professor Richard Lilford, Professor Miranda Mugford, Professor Ann Oakley, Professor Dafydd Walters and Mr John Williams. Appendices from Liggins and Howie; Liggins' Wellcome Trust grant; and the protocol of the 1975 UK trial of betamethasone, complete the volume. Reynolds L A, Tansey E M. (eds) (2005) Prenatal corticosteroids for reducing morbidity and mortality after preterm birth, Wellcome Witnesses to Twentieth Century Medicine, volume 25. London: The Wellcome Trust Centre for the History of Medicine at UCL.The Wellcome Trust Centre for the History of Medicine at UCL is funded by the Wellcome Trust, which is a registered charity, no. 210183

Birth outcomes for African and Caribbean babies in England and Wales: retrospective analysis of routinely collected data

Objectives: To compare mean birth weights, gestational ages and odds of preterm birth and low birth weight of live singleton babies of black African or Caribbean ethnicity born in 2005 or 2006 by mother's country of birth. Design: Secondary analysis of data from linked birth registration and NHS Numbers for Babies data set. Setting: Births to women in England and Wales in 2005 and 2006. Participants: Babies of African and Caribbean ethnicity born in England and Wales in 2005–2006, whose mothers were born in African and Caribbean countries or the UK. Birth outcomes for 51 599 singleton births were analysed. Main outcome measures: Gestational age and birth weight. Results: Mothers born in Eastern or Northern Africa had babies at higher mean gestational ages (39.38 and 39.41 weeks, respectively) and lower odds of preterm birth (OR=0.80 and 0.65, respectively) compared with 39.00 weeks for babies with mothers born in the UK. Babies of African ethnicity whose mothers were born in Middle or Western Africa had mean birth weights of 3327 and 3311 g, respectively. These were significantly higher than the mean birth weight of 3257 g for babies of the UK-born mothers. Their odds of low birth weight (OR=0.75 and 0.72, respectively) were significantly lower. Babies of Caribbean ethnicity whose mothers were born in the Caribbean had higher mean birth weight and lower odds of low birth weight than those whose mothers were born in the UK. Conclusions: The study shows that in babies of African and Caribbean ethnicity, rates of low birth weight and preterm birth varied by mothers' countries of birth. Ethnicity and country of birth are important factors associated with perinatal health, but assessing them singly can mask important heterogeneity in birth outcomes within categories particularly in relation to African ethnicity. These differences should be explored further

Comparative Network Analysis of Preterm vs. Full-Term Infant-Mother Interactions

Several studies have reported that interactions of mothers with preterm infants show differential characteristics compared to that of mothers with full-term infants. Interaction of preterm dyads is often reported as less harmonious. However, observations and explanations concerning the underlying mechanisms are inconsistent. In this work 30 preterm and 42 full-term mother-infant dyads were observed at one year of age. Free play interactions were videotaped and coded using a micro-analytic coding system. The video records were coded at one second resolution and studied by a novel approach using network analysis tools. The advantage of our approach is that it reveals the patterns of behavioral transitions in the interactions. We found that the most frequent behavioral transitions are the same in the two groups. However, we have identified several high and lower frequency transitions which occur significantly more often in the preterm or full-term group. Our analysis also suggests that the variability of behavioral transitions is significantly higher in the preterm group. This higher variability is mostly resulted from the diversity of transitions involving non-harmonious behaviors. We have identified a maladaptive pattern in the maternal behavior in the preterm group, involving intrusiveness and disengagement. Application of the approach reported in this paper to longitudinal data could elucidate whether these maladaptive maternal behavioral changes place the infant at risk for later emotional, cognitive and behavioral disturbance

Effect of various inspired oxygen concentrations on pulmonary and systemic hemodynamics and oxygenation during resuscitation in a transitioning preterm model.

BackgroundThe Neonatal Resuscitation Program recommends initial resuscitation of preterm infants with low oxygen (O2) followed by titration to target preductal saturations (SpO2). We studied the effect of resuscitation with titrated O2 on gas exchange, pulmonary, and systemic hemodynamics.MethodologyTwenty-nine preterm lambs (127 d gestation) were randomized to resuscitation with 21% O2 (n = 7), 100% O2 (n = 6), or initiation at 21% and titrated to target SpO2 (n = 16). Seven healthy term control lambs were ventilated with 21% O2.ResultsPreductal SpO2 achieved by titrating O2 was within the desired range similar to term lambs in 21% O2. Resuscitation of preterm lambs with 21% and 100% O2 resulted in SpO2 below and above the target, respectively. Ventilation of preterm lambs with 100% O2 and term lambs with 21% O2 effectively decreased pulmonary vascular resistance (PVR). In contrast, preterm lambs with 21% O2 and titrated O2 demonstrated significantly higher PVR than term lambs on 21% O2.Conclusion(s)Initial resuscitation with 21% O2 followed by titration of O2 led to suboptimal pulmonary vascular transition at birth in preterm lambs. Ventilation with 100% O2 in preterm lambs caused hyperoxia but reduced PVR similar to term lambs on 21% O2. Studies evaluating the initiation of resuscitation at a higher O2 concentration followed by titration based on SpO2 in preterm neonates are needed