Les progrès médicaux de la prise en charge des nouveau-nés prématurés ont permis la diminution de la mortalité néonatale, mais la prévalence des handicaps neurologiques d'origine périnatale reste stable. Ainsi, la mise en place de stratégies de neuroprotection est un enjeu primordial de la médecine périnatale actuelle. Parmi ces stratégies, l'administration de sulfate de magnésium en cas de menace d'accouchement prématuré permet l'amélioration du devenir neurologique des enfants à l'âge de deux ans. La neuroprotection concerne aussi l'ensemble des interventions qui ont lieu après la naissance, pendant la période néonatale. Depuis les années 2000, les agents anesthésiques sont mis en cause dans la survenue d'anomalies du développement lorsqu'ils sont administrés chez le nouveau-né. La balance bénéfice/risque doit donc être évaluée pour chaque anesthésique prescrit en période néonatale afin de limiter une potentielle neurotoxicité. La première partie de cette thèse a pour objectif le suivi à l'âge scolaire d'une cohorte d'enfants prématurés exposés en anténatal au sulfate de magnésium. La deuxième partie est consacrée à l'évaluation in vivo de l'impact du rémifentanil, morphinique de synthèse utilisé comme agent anesthésique, sur le cerveau immature du souriceau en condition excitotoxique. 1 - Etude de l'influence de l'administration anténatale du sulfate de magnésium sur le développement psychomoteur à l'âge scolaire de prématurés de moins de 33 semaines d'aménorrhée : essai Premag. L'étude Premag, débutée en France en 1997, avait permis l'inclusion de 688 nouveau-nés prématurés exposés au sulfate de magnésium ou à un placebo, dont 606 ont été suivis à l'âge de deux ans. Un suivi à plus long terme était nécessaire pour affirmer l'innocuité de la molécule sur le devenir neurocognitif à l'âge scolaire. Entre 'décembre 2009 et avril 2012, les familles qui avaient participé à l'essai Premag ont été recontactées. Quatre-cent-trente-et-un enfants (moyenne d'âge 11 ans) parmi les 606 survivants ont été évalués à l'âge scolaire par un questionnaire parental. Le critère d'évaluation principal était un critère combiné déficit moteur et/ou décès. Il n'a pas été mis en évidence d'effet délétère de l'exposition anténatale au sulfate de magnésium. Par ailleurs, une diminution non significative des troubles du comportement, une meilleure scolarisation et une réduction du recours aux services d'éducation à domicile ont été observées en cas d'exposition au sulfate de magnésium. 2 - Effet neuroprotecteur du rémifentanil dans un modèle murin de lésion excitotoxique néonatale. Le rémifentanil, morphinique de synthèse, est utilisé en période périnatale, chez la mère en cas d'anesthésie générale ou chez le nouveau-né en cas de nécessité d'anesthésie/analgésie. Nous avons évalué in vivo l'impact du morphinique en contexte lésionnel. Les lésions cérébrales ont été obtenues par administration intracorticale d'iboténate, agoniste glutamatergique, au deuxième jour de vie (P2) chez le souriceau. Après exposition au rémifentanil, la taille de la lésion induite par l'iboténate était significativement réduite à P7. Cet effet protecteur était accompagné par une diminution de la production des dérivés réactifs de l'oxygène et de l'astrogliose réactionnelle, suggérant un effet modulateur de la neuroinflammation par le rémifentanil. L'activité caspase était également réduite dans le groupe rémifentanil. Enfin, les performances sensori-motrices (géotaxie négative entre P6 et P8 et réflexe d'agrippement entre P10 et P12) étaient améliorées chez les animaux lésés exposés au morphinique. A P18, l'analyse du comportement des souris dans l'open field semblait suggérer que l'exposition au rémifentanil à P2 entraînait un effet anxiolytique, particulièrement chez les femelles. / Better protecting the developing brain of very preterm infants remains a dailychallenge for all specialists in perinatal care. Despite improvement of neonatal mortality andmorbidity, very preterm infants remain vulnerable and at risk of developing neurologicalimpairments. To limit the occurrence of such events, implementing of neuroprotectionduring brain development is essential. Neuroprotection in the context of preterm birth is thesubject of extensive research, but few strategies have currently been demonstrated to beeffective. One part of these strategies takes place before birth, as antenatal corticosteroidsadministration that is known to reduce intraventricular hemorrhage, or in utero transfer totertiary maternity hospitals. There is now strong evidence to support antenatal magnesiumsulfate infusion in order to prevent cerebral palsy in context of prematurity.Neuroprotection may also occur after birth and evaluate the benefit/risk balance for eachpotentially deleterious drug administered during this period, such as anesthetics, is one ofthose strategies. Fetuses and preterm newborns are exposed to general anesthesia duringcesarean delivery or in neonatal intensive care when sedation and analgesia isrecommended. The role of these agents remains extremely controversial and could appearto be neurotoxic.This thesis work is part of the development and evaluation of neuroprotectionstrategies for preterm neonates. The first part aims at the follow up of the French PREMAGcohort to evaluate the children for any long-term deleterious effects of magnesium sulfate,and to assess developmental and psychomotor outcomes at school-age. The second part isdevoted to the evaluation of the in vivo impact of remifentanil, synthetic opiate, on theimmature brain of mouse pups in an excitotoxic condition.

Within this review, sex-specific differences in alveolar epithelial functions are discussed with special focus on preterm infants and the respiratory disorders associated with premature birth. First, a short overview about fetal lung development, the challenges the lung faces during perinatal lung transition to air breathing and respiratory distress in preterm infants is given. Next, clinical observations concerning sex-specific differences in pulmonary morbidity of human preterm infants are noted. The second part discusses potential sex-specific causes of pulmonary complications, including pulmonary steroid receptors and local lung steroid metabolism. With regard to pulmonary steroid metabolism, it is important to highlight which steroidogenic enzymes are expressed at which stage during fetal lung development. Thereafter, we review the knowledge concerning sex-specific aspects of lung growth and maturation. Special focus is given to alveolar epithelial Na+ transport as a driver of perinatal lung transition and the sex differences that were noted in this process.

Thesis (MOccTher (Interdisciplinary Health Sciences. Occupational Therapy))--University of Stellenbosch, 2010. / AFRIKAANSE OPSOMMING: AGTERGROND Dit is bekend dat vroeggebore babas met ʼn baie lae geboortemassa ʼn hoër insidensie van ontwikkelings-, gedrags- en mediese agterstande en verskeie leerprobleme toon teen die tyd dat hulle skoolgaande ouderdom bereik. Kommer bestaan ook oor die omgewingseffek van die neonatale intensiewe sorgeenheid op die sensoriese ontwikkeling van die vroeggebore baba en hoe dit tot bogenoemde agterstande kan bydra. Daar is verskillende benaderings wat daarop aanspraak maak dat hulle die probleem kan oplos, met kangaroemoedersorg (‘kangaroo mother care’) en ontwikkelingsorg (‘developmental care’) wat in die literatuur uitgesonder is as besonders belowend. Met die aanvang van hierdie studie was daar nog geen empiriese studies in die literatuur gerapporteer wat enige aansprake van hierdie benaderings bevestig het nie. Daar was dus ʼn behoefte vir ʼn empiries-nagevorsde program wat prakties in die neonatale intensiewe eenheid toegepas kon word met die oog op die vermindering van omgewingstressors ten opsigte van die vroeggebore baba se sensoriese sisteme. DOEL Die doel met die studie was om die invloed te bepaal van ʼn Sensoriese Ontwikkelingsorgprogram (‘Sensory Developmental Care Programme’), wat ʼn spesifieke kangaroemoedersorg- protokol insluit, op die sensoriese ontwikkeling van die vroeggebore baba met 'ʼn baie lae geboortemassa tot en met die ouderdom van 18 maande (gekorrigeerde ouderdom). METODOLOGIE ʼn Ewekansig-gekontroleerde studie is uitgevoer. Die studiesteekproef het bestaan uit 89 vroeggebore babas met ʼn baie lae geboortemassa wat in ʼn periode van 24 maande toegelaat is tot die neonatale eenheid van Tygerberg Hospitaal in Kaapstad, Suid-Afrika. Die babas is gewerf op grond van sekere kriteria en is dan daarna ewekansig aan een van twee groepe toegeken: 1) die intervensiegroep het sorg ontvang volgens die Sensoriese Ontwikkelingsorgprogram vir 10 dae; en 2) die kontrolegroep het ook vir 10 dae die standaardsorg van die eenheid ontvang. Die intervensiegroep het uit 45 babas bestaan, van wie 22 die studie voltooi het, terwyl die kontrolegroep uit 44 babas bestaan het van wie 20 die studie voltooi het. Beide studiegroepe is opgevolg op 6, 12 en 18 maande (gekorrigeerde ouderdom), by welke geleentheid die Sensoriese Funksietoets vir Babas (‘Test of Sensory Functions in Infants’) telkens toegepas is vir die assessering van sensoriese ontwikkeling. Op 18 maande (gekorrigeerde ouderdom) is ʼn assessering met die Griffiths Ontwikkelingskaal ook gedoen om funksies in die ander ontwikkelingsareas van die babas te bepaal. Toetsresultate is geanaliseer met behulp van herhaalde ANOVAmetings en die Bonferoni t-prosedure om die effek van die Sensoriese Ontwikkelingsorgprogram op die sensoriese ontwikkeling van die babas tot en met 18 maande (gekorrigeerde ouderdom) te bepaal. RESULTATE Die resultate van die vergelyking van die prestasie van beide groepe (groep-effek), gemeet met behulp van die Sensoriese Funksietoets vir Babas, is van groot belang vir hierdie studie. Die intervensiegroep het betekenisvol verskil op die totale telling (p<0.00), sowel as op die volgende vier van die vyf subtoets-tellings: respons op diepdruk (‘tactile deep pressure’) (p<0.03); motoriese aanpassingsreaksies (p<0.03); visuele tas-integrasie (p<0.00); en respons op vestibulêre stimulasie (p<0.01). GEVOLGTREKKING Die resultate van die studie dui aan dat die babas in die intervensiegroep baat gevind het by die Sensoriese Ontwikkelingsorgprogram met betrekking tot hul sensoriese funksies tot en met die ouderdom van 18 maande (gekorrigeerde ouderdom). Die Sensoriese Ontwikkelingsorgprogram het geblyk prakties sowel as suksesvol te wees met betrekking tot sy doel. Die Program sou daarom met vrug in ander neonatale intensiewe sorgeenhede aangewend kon word. / ENGLISH ABSTRACT: BACKGROUND Premature infants of very low birth weight are known to be inclined to developmental, medical, behavioural and various learning deficiencies by the time they reach schoolgoing age. Concerns have been raised about the effect of the neonatal intensive care unit environment on the sensory development of the premature infant and how this could contribute to these deficiencies. Various approaches claim to address this problem, of which kangaroo mother care and developmental care have in the literature been singled out as particularly promising. However, at the commencement of this study no empirical studies had been reported in the literature to confirm any of the claims of these approaches. Therefore, a need existed for an empirically researched programme that could be practically applied in the neonatal intensive care unit with a view to reducing environmental stressors regarding the sensory systems of the premature infant. AIM The aim of this study was to determine the influence of a Sensory Developmental Care Programme, which incorporated a specific kangaroo mother care protocol, on the sensory development of the very low birth weight premature infant, up to the age of 18 months (corrected age). METHODOLOGY A randomised controlled study was conducted. The study sample consisted of 89 very low birth weight premature infants, admitted during a 24-month period to the neonatal care unit at Tygerberg Hospital in Cape Town, South Africa. The infants were recruited by means of certain criteria and then randomly assigned to one of two groups: 1) the intervention group was cared for according to the Sensory Developmental Care Programme for ten recorded days; and 2) the control group that received the standard care of the unit, also for ten days. The intervention group consisted of 45 infants of whom 22 completed the study, while the control group consisted of 44 infants of whom 20 completed the study. Both study groups were followed up at six, 12 and 18 months (corrected age) when the Test of Sensory Functions in Infants was used to do a sensory developmental assessment. At 18 months (corrected age) a Griffiths Developmental Scale assessment was also conducted to determine function in other areas of development. Test results were analysed using repeated measures of ANOVA, and the Bonferoni t procedure to determine the effect that the Sensory Developmental Care Programme had on the sensory development of the infant up to 18 months (corrected age). RESULTS The results of the comparison of the performance of both groups (group effect), measured by the Test of Sensory Functions in Infants are of great importance to this study. The intervention group had a significant difference on the total score (p<0.00), as well as on the following four of the five sub-tests scores: reactivity to tactile deep pressure (p<0.03); adaptive motor functions (p<0.03); visual-tactile integration (p<0.00); and reactivity to vestibular stimulation (p<0.01). CONCLUSION The results of this study signify that the infants in the intervention group benefited from the Sensory Developmental Care Programme concerning their sensory functions up to the age of 18 months (corrected age). The Sensory Developmental Care Programme was demonstrated to be both practical and successful in terms of its aims. The Programme could therefore be fruitfully utilised in other neonatal intensive care units.

Background Modern neonatal care has improved the survival rate of extremely preterm infants. These infants are at high risk of malnutrition and growth failure during 3-4 months of hospital care. The objectives of this study was to investigate nutritional intakes during hospitalization and explore associations between nutritional intakes, postnatal growth and retinopathy of prematurity (ROP). Perioperative nutrition in infants undergoing surgery for patent ductus arteriosus (PDA) was also investigated. Methods This is a population-based study of Swedish extremely preterm infants (&lt;27 weeks) born during 2004-2007 (n=602). Detailed data on nutritional supply and anthropometric measurements during hospitalization were retrospectively retrieved from hospital records. Comprehensive data on cohort characteristics, neonatal morbidity and infant mortality were obtained from the Extremely Preterm Infants in Sweden Study (EXPRESS). Results During the first 70 days of life, intakes of energy, protein and several micronutrients, with the exception of iron and some vitamins, were less than estimated requirements, and infants showed severe postnatal growth failure. Energy and protein intake predicted growth in all anthropometric outcomes even when adjusting for severity of illness, and fat intake was positively associated with head growth. Low folate intake was positively correlated with poor weight and length gain while high iron intake, mainly explained by blood transfusions, was negatively associated with poor length gain. Furthermore, a low energy intake was associated with severe ROP (stage 3-5). An increased energy intake of 10 kcal/kg/d was associated with 24% decrease in severe ROP (p=0.01). During the first month, 99% of the infants were exclusively fed human milk. Infants who underwent surgery for PDA (n=140) were malnourished, with energy and macronutrient intakes below minimum estimated requirements before, during and after surgery. Conclusions The severe postnatal growth failure observed in Swedish extremely preterm infants may be prevented by improved intakes of energy, protein, fat and folate and a reduction of the number of blood transfusions. Human milk is the main enteral food source and analyses of human milk macronutrient contents facilitates individualized fortification. Provision of adequate energy intakes during the first four weeks of life may be an effective way to reduce the risk of severe ROP. Perioperative nutrition in infants undergoing PDA surgery needs to be improved. The study results have important implications for nutritional regimens, postnatal growth and health outcome in this new generation of survivors.

Diversos fatores de risco biológicos e ambientais estão envolvidos na trajetória de desenvolvimento de bebês pré-termo. O presente estudo teve por objetivos avaliar os indicadores de risco ou atraso para problemas no desenvolvimento de bebês nascidos pré-termo e baixo peso, focalizando o desenvolvimento neurocomportamental na fase neonatal, desenvolvimento pessoal-social, linguagem e motor nos oito primeiros meses de idade pós-natal; identificar o melhor modelo de predição para os indicadores de risco ou atraso na trajetória de desenvolvimento dos bebês, baseado nas variáveis biológicas e socioeconômicas; analisar a trajetória de desenvolvimento dos bebês nascidos pré-termo por meio do acompanhamento longitudinal desde o período neonatal até oito meses de idade cronológica corrigida (ICC); avaliar os parâmetros psicométricos de validade concorrente do Teste de Denver II e avaliação do desenvolvimento motor e validade preditiva do NAPI e Teste de Denver II. A amostra foi constituída por 190 bebês nascidos pré-termo com baixo peso ao nascimento, provenientes da UTIN do Hospital Materno Infantil em Goiânia (GO). Na avaliação utilizou-se os instrumentos Neurobehavioral Assessment of Preterm Infant (NAPI) na fase neonatal, Teste de Triagem do Desenvolvimento de Denver II entre 2 e 8 meses de ICC, Test of Infant Motor Performance (TIMP) entre 2 e 4 meses de ICC, Alberta Infant Motor Scale (AIMS), entre 4 e 8 meses de ICC. O procedimento de coleta envolveu visitas à unidade neonatal de médio risco para avaliação dos bebês na fase neonatal ainda no período de internação hospitalar e avaliações subseqüentes de seguimento no Ambulatório de Alto Risco do referido Hospital. Os dados de caracterização das crianças foram analisados por meio de estatística descritiva. Na análise de comparação entre grupos foram utilizados os testes Qui-quadrado e t de Student. Na análise de predição foram realizados testes de regressão logística. Em todas as análises realizadas foi adotado o nível de significância de 5%. Os resultados demonstraram que 31% dos bebês apresentaram atrasos no desenvolvimento neurocomportamental na fase neonatal. Em relação ao desenvolvimento global avaliado pelo teste de Denver II, 51% revelou risco para problemas entre 2 e 4 meses de ICC, 43% entre 4 e 6 meses de ICC e 33% entre 6 e 8 meses de ICC Quanto ao desenvolvimento motor, 48% dos bebês apresentaram atraso entre 2 e 4 meses de ICC, 47% entre 4 e 6 meses de ICC e 36% entre 6 e 8 meses de ICC. Ao comparar o desempenho dos bebês nas idades cronológica e corrigida, verificou-se a necessidade de realizar a correção da idade em todas as faixas etárias avaliadas. Verificou-se que fatores de risco tais como: peso <1.500g, idade gestacional 32 semanas, alto risco clínico neonatal, presença de hemorragias intracranianas, aleitamento materno artificial, baixa escolaridade do chefe da família, maior densidade de pessoas na residência, número reduzido de cômodos na casa e nível sócio-econômico baixo foram as principais variáveis de maior influência no risco e atraso no desenvolvimento. Os bebês acompanhados longitudinalmente apresentaram 24% de atraso na avaliação neurocomportamental na fase neonatal e manutenção da taxa de risco no desenvolvimento global e atraso no desenvolvimento motor entre 2 e 8 meses de ICC. Quanto ao estudo da validade concorrente, verificou-se que o Teste de Denver II apresentou concordância de 64% com o teste TIMP entre 2 e 4 meses de ICC, 89% com a escala AIMS entre 4 e 6 meses de ICC e 82% com a escala AIMS entre 6 e 8 meses de ICC. Em relação a validade preditiva, verificou-se que a avaliação NAPI apresentou associações com o desenvolvimento motor e global e o teste de Denver apresentou concordância 52% nas faixas etárias avaliadas pela AIMS. / Several biological and environmental risk factors influence the development of preterm infants. The objective of this study was to assess risk factors for development delay in preterm infants born with low birth weight, focusing on the following domains: neurobehavioral achievements in the neonatal phase, as well as personal-social, language and motor developments in the first 8 months of postnatal age. We also aimed to: identify the better predictive model for development, based on the biological and socioeconomic variables measured in our sample of low birth weight preterm; to longitudinally follow and to describe the development of these infants during the first 8 months of corrected chronological age (CA); to test the psychometric parameters and to estimate the predictive value of the Neurobehavioral Assessment of Preterm Infant (NAPI) and Denver II tests (DDST-II), in assessing the motor development of the infants. Our sample consisted of 190 preterm infants (< 37 weeks of gestational age) and with low birth weight (<2,500 grams) seen during their first year of age, born and initially assisted at a neonatal specialty center at the Infant Maternity Hospital of Goiania (GO), Brazil. At the neonatal phase, the infants were assessed using the NAPI test; from 2-4 months of CA, we used the Test of Infant Motor Performance (TIMP); from 4-6 months and 6-8 months of CA, we used, the DDST-II; from 6-8 months of CA, we used the Alberta Infant Motor Scale (AIMS). Initial assessments were performed in the neonatal unit of intermediate risk (while the infants were hospitalized); subsequent assessments were conducted in our outpatient hospital clinic (ambulatory) for high risk infants. Descriptive statistics included mean, range, and standard deviation for continuous variables, and frequency and percentage for categorical variables. The in-between group comparisons were conducted using the Chi-square Test or Student T Test. For predictive assessments, we used logistical regression. The significance level for each test was set at 5%. Over 31% of the infants in our sample showed signs of impaired neurobehavioral development in the neonatal phase. Infants assessed from 2-4 months of CA had 51% of risk for developmental problems according to the DDST-II; 48% obtained abnormal classifications in the TIMP. Similarly, 43 % of the infants were at risk in the DDST-II, and 47% had abnormal motor development according to the AIMS at 4-6 months of CA. At 6-8 months of CA, 33% of the infants were at risk as per the DDST-II, and 36% of the infants had abnormal motor development according to the AIMS. When comparing the development of the infants as per the chronological and corrected age, it became evident the needs for correcting the age in all assessed age-ranges. The main variables imposing risk and influencing the development of our sample were: weight <1.500g; gestational age 32 weeks; high neonatal clinical risk; presence of intracranial hemorrhage; lack of natural breast feeding; low levels of education by the household head; number of individuals living in the household; reduced number of rooms in the household; low socio-economic level. The 80 infants that were longitudinally followed had 24% of delay, as measured by the neurobehavioral assessment conducted in the neonatal phase, and mantained the risk levels for global development, as well as deleyed in motor development between 2 to 8 months of CA. Regarding our concurrent validty study, the DDST-II test showed 64% of agreement with the TIMP test between 2 and 4 months of CA; the agreement with AIMS betwen 4 and 6 months of CA was 89%, and from 6-8 months of CA it was 82%. Regarding the predictive values, the NAPI assessment for motor and global developments agreeed with the DDST-II test in 52%, in the age ranges measured by the AIMS.

Even though initiation of breastfeeding among term and preterm infants has increased, the incidence and duration among preterm infants continues to lag because of the unique challenges of breastfeeding preterm infants. African American mothers have the lowest rates of breastfeeding initiation and duration, and their preterm infants are less likely to receive breast milk while in the neonatal intensive care unit. The objective of this cross-€sectional quantitative study was to evaluate the relationship between breastfeeding and maternal sociodemographic factors as well as medical and obstetrical conditions for infants born between 32-€37 weeks gestational age in South Carolina from 2009 to 2011. The health belief model provided the framework for this study. Secondary data from the South Carolina Pregnancy Risk Assessment Monitoring System included 1,752 preterm pregnancies. Results of binary logistic regression and multivariate logistic regression analysis indicated that mothers who were African American and those who had lower income, no Medicaid, and lower education level breastfed less frequently. Findings may be used to decrease neonatal, postnatal, and infant morbidity and mortality, and to increase breastfeeding knowledge and support to ensure successful breastfeeding of preterm infants beyond the hospital.

A prematuridade está associada com uma alta incidência de complicações no período neonatal sendo uma das mais importantes a retinopatia da prematuridade (ROP) e suas seqüelas: ambliopia, estrabismo, cegueira. Estudos indicam que alterações no fluxo sanguíneo retiniano estão envolvidas na patogênese da ROP causando um crescimento vascular anormal dos vasos da retina. A análise por ultrassonografia Doppler (USD) dos vasos da órbita permite uma estimativa do fluxo sanguíneo local. Objetivo: estabelecer valores de velocidade do fluxo sanguíneo e de seus índices na artéria oftálmica em recém-nascidos pré-termos de muito baixo peso (RNPTMBP) "saudáveis" do nascimento até a alta. Metodologia: Coorte de recémnascidos pré-termos de muito baixo peso, nascidos na UTI Neonatal do Hospital de Clínicas de Porto Alegre (HCPA) no período de agosto de 2006 a abril de 2008. Foram obtidas as medidas de velocidade sistólica (VS), velocidade diastólica (VD), índice de pulsatilidade (IP) e índice de resistência (IR) da artéria oftálmica por USD nas primeiras 24 horas de vida, com sete dias, com 28 dias e no momento da alta hospitalar. Incluímos RN com peso de nascimento abaixo de 1500 gramas e idade gestacional <= 32 semanas, sem ROP graus 2 e 3, e sem hemorragia peri-intraventricular (HPIV) graus 3 e 4. A análise estatística foi realizada utilizando teste t pareado e análise de variância (ANOVA). Resultados: Foram estudados 46 RNPTMBP (92 olhos examinados). No primeiro exame os valores em média do fluxo sanguíneo e índices da artéria oftálmica foram: VS 18,42 cm/s; VD 6,22 cm/s; IP 1,40; IR 0,70 e com 28 dias de vida: VS 22,38 cm/s; VD 6,97 cm/s; IP 1,51; IR 0,75 (p<0.001). Não houve diferença significativa entre as medidas obtidas no olho direito e no esquerdo, e entre primeiro e segundo exames. Da mesma forma, as medidas obtidas com 28 dias de vida foram similares aquelas no momento da alta hospitalar. Conclusão: Ocorre uma elevação nas velocidades de fluxo sanguíneo da artéria oftálmica do período pós-natal até a alta em recémnascidos pré-termo de muito baixo peso de nascimento "saudáveis". Os índices calculados não mostraram diferença estatisticamente significativa. O conhecimento deste padrão normal poderá auxiliar na prevenção e no screening para detecção de doença ocular. / Retinopathy of prematurity (ROP) is a multifactorial disease of very low birth weight infants (VLBWI), and the vascular component has an important role. Evaluation of retinal blood flow is essential to understand its physiopathology. Objective: To establish normal blood flow velocity and Doppler indices of the ophthalmic arteries from birth to discharge of "healthy" VLBWI.Methods: Cohort study of newborns with birth weight < 1500 grams and gestational age <= 32 weeks born at our Hospital from August 2006 to April 2008. Doppler ultrasound exam was done in both eyes in the first 24 hours after birth, at 7 and 28 days old, and at hospital discharge for systolic velocity (SV), diastolic velocity (DV), pulsatility index (PI) and resistance index (RI). We excluded those with ROP stage 2 and higher, periintraventricular hemorrhage grades 3 and 4, and death. Statistical analysis was performed using paired t test and repeated measures ANOVA. The study was approved by our Ethic Committee.Results: 46 VLBWI (92 eyes) were studied. First exam: SV 18.40 cm/s; DV 6.23 cm/s; PI 1.41; RI 0.70 and 28 days after birth: SV 22.30 cm/s; DV 6.77 cm/s; PI 1,50; RI 0.75 ( p<0.001). Both eyes had similar Doppler findings at all examined moments. SV and DV increased significantly from the first 24 hours to hospital discharge. There were no significant changes during the study period in PI and RI. Conclusions: There was a increase of SV and DV retinal blood flow from birth to hospital discharge in "healthy" VLBWI; other Doppler measurements were stable. Knowing this normal pattern will provide prevention and screening for ROP.

A prematuridade está associada com uma alta incidência de complicações no período neonatal sendo uma das mais importantes a retinopatia da prematuridade (ROP) e suas seqüelas: ambliopia, estrabismo, cegueira. Estudos indicam que alterações no fluxo sanguíneo retiniano estão envolvidas na patogênese da ROP causando um crescimento vascular anormal dos vasos da retina. A análise por ultrassonografia Doppler (USD) dos vasos da órbita permite uma estimativa do fluxo sanguíneo local. Objetivo: estabelecer valores de velocidade do fluxo sanguíneo e de seus índices na artéria oftálmica em recém-nascidos pré-termos de muito baixo peso (RNPTMBP) "saudáveis" do nascimento até a alta. Metodologia: Coorte de recémnascidos pré-termos de muito baixo peso, nascidos na UTI Neonatal do Hospital de Clínicas de Porto Alegre (HCPA) no período de agosto de 2006 a abril de 2008. Foram obtidas as medidas de velocidade sistólica (VS), velocidade diastólica (VD), índice de pulsatilidade (IP) e índice de resistência (IR) da artéria oftálmica por USD nas primeiras 24 horas de vida, com sete dias, com 28 dias e no momento da alta hospitalar. Incluímos RN com peso de nascimento abaixo de 1500 gramas e idade gestacional <= 32 semanas, sem ROP graus 2 e 3, e sem hemorragia peri-intraventricular (HPIV) graus 3 e 4. A análise estatística foi realizada utilizando teste t pareado e análise de variância (ANOVA). Resultados: Foram estudados 46 RNPTMBP (92 olhos examinados). No primeiro exame os valores em média do fluxo sanguíneo e índices da artéria oftálmica foram: VS 18,42 cm/s; VD 6,22 cm/s; IP 1,40; IR 0,70 e com 28 dias de vida: VS 22,38 cm/s; VD 6,97 cm/s; IP 1,51; IR 0,75 (p<0.001). Não houve diferença significativa entre as medidas obtidas no olho direito e no esquerdo, e entre primeiro e segundo exames. Da mesma forma, as medidas obtidas com 28 dias de vida foram similares aquelas no momento da alta hospitalar. Conclusão: Ocorre uma elevação nas velocidades de fluxo sanguíneo da artéria oftálmica do período pós-natal até a alta em recémnascidos pré-termo de muito baixo peso de nascimento "saudáveis". Os índices calculados não mostraram diferença estatisticamente significativa. O conhecimento deste padrão normal poderá auxiliar na prevenção e no screening para detecção de doença ocular. / Retinopathy of prematurity (ROP) is a multifactorial disease of very low birth weight infants (VLBWI), and the vascular component has an important role. Evaluation of retinal blood flow is essential to understand its physiopathology. Objective: To establish normal blood flow velocity and Doppler indices of the ophthalmic arteries from birth to discharge of "healthy" VLBWI.Methods: Cohort study of newborns with birth weight < 1500 grams and gestational age <= 32 weeks born at our Hospital from August 2006 to April 2008. Doppler ultrasound exam was done in both eyes in the first 24 hours after birth, at 7 and 28 days old, and at hospital discharge for systolic velocity (SV), diastolic velocity (DV), pulsatility index (PI) and resistance index (RI). We excluded those with ROP stage 2 and higher, periintraventricular hemorrhage grades 3 and 4, and death. Statistical analysis was performed using paired t test and repeated measures ANOVA. The study was approved by our Ethic Committee.Results: 46 VLBWI (92 eyes) were studied. First exam: SV 18.40 cm/s; DV 6.23 cm/s; PI 1.41; RI 0.70 and 28 days after birth: SV 22.30 cm/s; DV 6.77 cm/s; PI 1,50; RI 0.75 ( p<0.001). Both eyes had similar Doppler findings at all examined moments. SV and DV increased significantly from the first 24 hours to hospital discharge. There were no significant changes during the study period in PI and RI. Conclusions: There was a increase of SV and DV retinal blood flow from birth to hospital discharge in "healthy" VLBWI; other Doppler measurements were stable. Knowing this normal pattern will provide prevention and screening for ROP.

A prematuridade está associada com uma alta incidência de complicações no período neonatal sendo uma das mais importantes a retinopatia da prematuridade (ROP) e suas seqüelas: ambliopia, estrabismo, cegueira. Estudos indicam que alterações no fluxo sanguíneo retiniano estão envolvidas na patogênese da ROP causando um crescimento vascular anormal dos vasos da retina. A análise por ultrassonografia Doppler (USD) dos vasos da órbita permite uma estimativa do fluxo sanguíneo local. Objetivo: estabelecer valores de velocidade do fluxo sanguíneo e de seus índices na artéria oftálmica em recém-nascidos pré-termos de muito baixo peso (RNPTMBP) "saudáveis" do nascimento até a alta. Metodologia: Coorte de recémnascidos pré-termos de muito baixo peso, nascidos na UTI Neonatal do Hospital de Clínicas de Porto Alegre (HCPA) no período de agosto de 2006 a abril de 2008. Foram obtidas as medidas de velocidade sistólica (VS), velocidade diastólica (VD), índice de pulsatilidade (IP) e índice de resistência (IR) da artéria oftálmica por USD nas primeiras 24 horas de vida, com sete dias, com 28 dias e no momento da alta hospitalar. Incluímos RN com peso de nascimento abaixo de 1500 gramas e idade gestacional <= 32 semanas, sem ROP graus 2 e 3, e sem hemorragia peri-intraventricular (HPIV) graus 3 e 4. A análise estatística foi realizada utilizando teste t pareado e análise de variância (ANOVA). Resultados: Foram estudados 46 RNPTMBP (92 olhos examinados). No primeiro exame os valores em média do fluxo sanguíneo e índices da artéria oftálmica foram: VS 18,42 cm/s; VD 6,22 cm/s; IP 1,40; IR 0,70 e com 28 dias de vida: VS 22,38 cm/s; VD 6,97 cm/s; IP 1,51; IR 0,75 (p<0.001). Não houve diferença significativa entre as medidas obtidas no olho direito e no esquerdo, e entre primeiro e segundo exames. Da mesma forma, as medidas obtidas com 28 dias de vida foram similares aquelas no momento da alta hospitalar. Conclusão: Ocorre uma elevação nas velocidades de fluxo sanguíneo da artéria oftálmica do período pós-natal até a alta em recémnascidos pré-termo de muito baixo peso de nascimento "saudáveis". Os índices calculados não mostraram diferença estatisticamente significativa. O conhecimento deste padrão normal poderá auxiliar na prevenção e no screening para detecção de doença ocular. / Retinopathy of prematurity (ROP) is a multifactorial disease of very low birth weight infants (VLBWI), and the vascular component has an important role. Evaluation of retinal blood flow is essential to understand its physiopathology. Objective: To establish normal blood flow velocity and Doppler indices of the ophthalmic arteries from birth to discharge of "healthy" VLBWI.Methods: Cohort study of newborns with birth weight < 1500 grams and gestational age <= 32 weeks born at our Hospital from August 2006 to April 2008. Doppler ultrasound exam was done in both eyes in the first 24 hours after birth, at 7 and 28 days old, and at hospital discharge for systolic velocity (SV), diastolic velocity (DV), pulsatility index (PI) and resistance index (RI). We excluded those with ROP stage 2 and higher, periintraventricular hemorrhage grades 3 and 4, and death. Statistical analysis was performed using paired t test and repeated measures ANOVA. The study was approved by our Ethic Committee.Results: 46 VLBWI (92 eyes) were studied. First exam: SV 18.40 cm/s; DV 6.23 cm/s; PI 1.41; RI 0.70 and 28 days after birth: SV 22.30 cm/s; DV 6.77 cm/s; PI 1,50; RI 0.75 ( p<0.001). Both eyes had similar Doppler findings at all examined moments. SV and DV increased significantly from the first 24 hours to hospital discharge. There were no significant changes during the study period in PI and RI. Conclusions: There was a increase of SV and DV retinal blood flow from birth to hospital discharge in "healthy" VLBWI; other Doppler measurements were stable. Knowing this normal pattern will provide prevention and screening for ROP.

Les enfants nés prématurément, et plus particulièrement les grands prématurés nés avant<p>31 semaines d’âge gestationnel, sont à haut risque de contracter des infections. La<p>vaccination peut prévenir certaines infections, dont la coqueluche qui est causée par la<p>bactérie Bordetella pertussis (Bp). Cependant, cette maladie infectieuse hautement<p>contagieuse est en recrudescence depuis plusieurs années malgré une bonne couverture<p>vaccinale. La morbidité et surtout la mortalité de la coqueluche affectent plus<p>particulièrement les jeunes enfants, incomplètement ou non encore vaccinés.<p>Il existe deux types de vaccins contre B. pertussis :les vaccins de première génération à<p>cellules entières et les vaccins acellulaires, plus récents. Suite à l’apparition d’effets<p>secondaires causés par le vaccin à cellules entières, les vaccins acellulaires, comprenant<p>seulement un certain nombre d’antigènes purifiés de B. pertussis, sont utilisés en Belgique<p>comme dans de nombreux autres pays industrialisés.<p>L’immunité protectrice contre B. pertussis fait appel tant à l’immunité cellulaire qu‘à<p>l’immunité humorale. De nombreuses études ont démontré une production d’anticorps<p>spécifiques aux antigènes de B. pertussis suite à l’administration des différents types de<p>vaccins. Par contre, peu d’entre elles ont analysé la réponse d’immunité cellulaire spécifique<p>caractérisée, entre autres, par une sécrétion d’Interféron-gamma (IFN-& / Doctorat en Sciences médicales / info:eu-repo/semantics/nonPublished