[Consequences of premature rupture of the membranes in the perinatal lung]. / Physiopathologie des conséquences respiratoires néonatales de la rupture prématurée des membranes: application à la prise en charge néonatale.

Early premature rapture of the membranes (PROM) during pregnancy is associated with a high risk of perinatal morbidity and mortality. Early PROM impairs lung structures and function through 3 mechanisms : 1) oligo-hydramnios ; 2) fetal inflammatory syndrome ; and 3) prematurity. Thus, the related causes of respiratory failure at birth after PROM are: hyaline membrane disease, persistent pulmonary hypertension induced by impaired endothelial function and/or lung hypoplasia, materno-fetal infection, and bronchopulmonary dysplasia resulting at least in part from the fetal inflammatory syndrome. Severity of the respiratory morbidity is largely unpredictable. Even if gestational age at PROM is considered as a prognostic factor, survival without morbidity exist after PROM as early as 18 weeks GA. Better knowledge of the pathophysiology improved the outcome of the preterm infants born after early PROM. Optimal management of the respiratory failure including minimizing barotrauma is required to prevent from bronchopulmonary dysplasia.

Intrauterine tobacco smoke exposure and hyaline membrane disease amongst triplets.

We assessed the association between prenatal smoking and respiratory distress syndrome (RDS) among triplets using a population-based retrospective cohort of 12,169 triplet live births in the United States between 1995 and 1997. Analysis was conducted using the generalised estimating equation framework to adjust for intra-cluster correlations. A total of 938 cases of RDS were reported comprising 35 among smoking (7.2%) and 903 among non-smoking gravidas (7.7%). The likelihood of RDS was comparable in both smoking categories [adjusted odds ratio (OR) = 0.93; 95% confidence interval (CI) = 0.65-1.32]. The risk for RDS due to smoking diminished with declining birth weight albeit non-significantly: low birth weight (OR = 0.99; 95% CI = 0.40-2.42), very low birth weight (OR = 0.85; 95% CI = 0.39-1.86), and extremely low birth weight (OR = 0.69; 95% CI = 0.30-1.58). In conclusion, among triplet neonates, smoking during pregnancy was not associated with respiratory distress syndrome.

[Congenital diaphragmatic hernia. II. Is pulmonary hypoplasia an indefinable obstacle?]. / Hernie diaphragmatique congénitale II. L'hypoplasie pulmonaire, obstacle incontournable?

Despite major insights into the pathogenesis and pathophysiology of congenital diaphragmatic hernia, and despite the availability of an antenatal diagnosis and continuous progress in neonatal intensive care, little improvement has been obtained in the prognosis of this malformation. Thus obstetricians, neonatologists and pediatric surgeons are still facing a several dilemma: dilemma before birth to predict the prognosis, i.e., to evaluate the severity of the associated pulmonary hypoplasia in order to decide whether or not to interrupt pregnancy; dilemma after birth in case of severe respiratory failure to decide how far to go in life support. Based on a review of the literature and their own experience, the authors attempt to recapitulate the perinatal management and outcome of this severe malformation.

The effects of IL-10 on proinflammatory cytokine expression (IL-1beta and IL-8) in hyaline membrane disease (HMD).

Deficient expression of the counterregulatory cytokine IL-10 by lung inflammatory cells may facilitate chronic inflammation and the pathogenesis of hyaline membrane disease (HMD), in premature infants. To determine if pathways which regulate proinflammatory cytokines in response to human recombinant IL-10 (rIL-10) were functional in the lungs of these neonates, bronchoalveolar lavage (BAL)-derived lung inflammatory cells (predominantly macrophages and neutrophils) from infants with HMD were cultured in the presence of lipopolysaccharide (LPS) and increasing concentrations of (rIL-10). The expression of IL-1beta and IL-8 protein was assessed 24 h later. IL-10 protein was also measured from the BAL aspirates of these newborns at 4-day intervals over the first month of life. In cell culture IL-1beta expression was inhibited by rIL-10 in a dose-dependent fashion while IL-8 expression was inhibited by higher concentrations of rIL-10. IL-10 protein was undetectable from BAL fluid of the premature infants sampled over 28 days. The results demonstrate that lung inflammatory cells, which do not express IL-10 in vivo, are capable of responding to rIL-10 in cell culture with reduction of IL-1beta and IL-8 expression. These data support the rationale for the development of rIL-10 as a potential anti-inflammatory agent in the treatment of HMD.

Bilateral multicystic kidney dysplasia in a fetus with neonatal pulmonary hyaline membrane disease: a case report.

Multicystic kidney disease is the most common cause of neonatal renal mass and either the most or second most common neonatal abdominal mass. This disease is a congenital dysplasia of the kidney characterized by large nonhomogeneous dilations of the collecting tubules. It may occur unilaterally or bilaterally, and the incidence is about 1 out of 5,000 to 10,000 births. Severe bilateral defects are lethal. Partial dysplastic involvement of both kidneys eventually leads to renal function impairment. This is a case of bilateral multicystic kidney dysplasia diagnosed prenatally at 34 weeks of gestation. Hyaline membrane disease was found in both lungs after delivery. The antenatal diagnostic criteria for multicystic kidney disease and treatment after diagnosis are also discussed.

Síndrome de dificultad respiratoria / Respiratory distress syndrome

Con el objeto de uniformar su denominación y facilitar la interpretación de las publicaciones sobre ellas en el país, se sugieren criterios para la caracterización de algunas afecciones respiratorias de los recién nacidos. Se propone hablar de enfermedad de membrana hialina (o síndrome de dificultad respiratoria del prematuro por déficit de surfactante) en casos de prematurez y déficit de surfactante; requerimientos precoces (antes de transcurridas 6 horas desde el nacimiento) de O2, progresivamente mayores y de duración igual o mayor a tres días; opacidad difusa, broncograma aéreo y disminución de volumen pulmonar en las radiografías de tórax. El pulmón inmaduro se caracteriza por prematurez (menos de 28 semanas de edad gestacional), insuficiencia respiratoria causada principalmente por inmadurez morfológica del pulmón, requerimientos de O2 en general bajos (no obstante requieran ventilación mecánica), no progresivos y de duración igual o mayor a 7 días, con alteraciones pulmonares mínimas inespecíficas, con volumen pulmonar conservado en las radiografías de tórax. El pulmón húmedo o taquipnea transitoria es un trastorno en que los antecedentes no son requisitos determinantes para hacer el diagnóstico y sus manifestaciones clínicas son taquipnea; aumento de los requerimientos de O2, generalmente no progresivos y de corta duración igual o menor a 5 días; infiltrado intersticial, cisuras visibles y aumento del volumen pulmonar en las radiografias de tórax

Prolonged premature rupture of membranes in the preterm infant: a 7 year study.

AIM: To review the outcome of infants born following prolonged and preterm rupture of the membranes. DESIGN: retrospective and partially prospective observational study. SETTING: babies born in and referred to a tertiary neonatal centre. PATIENTS: 117 preterm infants, median gestation (range) = 29.5 (25-36) weeks, seen over a 7 year period with membranes ruptured for more than 4 days; median (range) = 9 (4-119) days. OUTCOME MEASURES: survival and cause of death, compression deformities, pulmonary hypoplasia and infection. RESULTS: 23 infants died, 11 from pulmonary hypoplasia and 11 as a direct consequence of prematurity (3 from hyaline membrane disease, 7 from bronchopulmonary dysplasia and one from necrotising enterocolitis developed on day 17). One infant had a lethal congenital abnormality and died untreated of overwhelming infection. No other infants died of infection. 94% of infants were treated with broad-spectrum antibiotics after birth. Compression deformities were seen in 25 infants: median duration of membrane rupture 28 days, range 4-119. In those without deformity, median duration was 7 days, range 4-105. Sixteen infants had pulmonary hypoplasia (median 31, range 14-119), 11 died (median 37, range 21-112) and five survived (median 23, range 14-119). Although the median duration of membrane rupture in infants dying of pulmonary hypoplasia was longer than in those who did not have hypoplasia (31 compared to 7 days), 13 of 27 (48%) of infants whose membranes were ruptured for 4 weeks and 4 of 7 (57%) whose membranes were ruptured more than 70 days survived. CONCLUSION: death from pulmonary hypoplasia is a much more serious problem following preterm prolonged membrane rupture than is infection. Pulmonary hypoplasia is not inevitable even after prolonged periods of membrane rupture.

Impacto económico del uso de surfactante pulmonar sintético para el tratamiento de la enfermedad de membrana hialina en recién nacidos prematuros

El uso de surfactante pulmonar para el manejo de la enfermedad de membrana hialina constituye uno de los mayores logros de la medicina neonatal en los últimos años. Diferentes estudios clínicos han demostrado ampliamente los beneficios del uso del surfactante en prematuros con membrana hialina. La efectividad de su uso está plenamente comprobada, y teniendo en cuenta que la meta que se busca con su uso es disminuir la incidencia de displasia broncopulmonar y la mortalidad generada por la enfermedad, consideramos que su utilización tiende a reducir los costos finales de tratamiento por disminución del tiempo de ventilación asistida y las complicaciones. Basados en lo anterior, quisimos conocer los costos finales de tratamiento generados, por la enfermedad de membrana hialina, en un grupo de pacientes de la ciudad de Bogotá, ya que dados los limitados recursos económicos y locativos que tenemos para la atención del recién nacido de alto riesgo es importante conocer que terapia brinda los mejores resultados a un costo menor en nuestro país. Nosotros realizamos un estudio de identificación de costos generados por la enfermedad, en un grupo de pacientes manejados con y sin surfactante pulmonar. Encontramos que la terapia con surfactante pulmonar disminuye el tiempo de ventilación asistida (67 hr vs 100 hr p=0.26) y la mortalidad (4.54 por ciento vs 13.6 por ciento p=0.57). El costo final de tratamiento fue menor en el grupo con surfactante (2ï455.000 vs 2ï813.000 pesos p>0.05). De acuerdo con nuestros resultados podemos concluir que el uso de surfactante pulmonar no incrementa los costos de manejo de la enfermedad de membrana hialina.

Evolución del peso en neonatos con enfermedad de membrana hialina

Se analizó el comportamiento del peso de 18 recién nacidos con enfermedad de membrana hialina que no presentaban ninguna patología asociada de tipo quirúrgico, infeccioso o malformación congénita. El objetivo principal fue demostrar si la evolución del peso estaba asociada al aporte hidrocalórico suministrado por vía parenteral o enteral, o si por el contrario existen otros fenómenos que condicionan la ganancia de peso. Se comparó el aporte promedio de calorías, proteínas y líquidos suministrados por cada una de las vías de alimentación encontalizadas no se presentaron diferencias significativas. Se analizaron características de la muestra en relación con sexo, edad gestacional, peso al nacer, vía de nacimiento, talla, perímetro cefálico, antecedentes maternos y complicaciones que pueden ser determinantes en la aparición de la enfermedad de membrana hialina. También se observó y analizó el comportamiento del puntaje de Apgar, medición utilizada para medir el estado fisiológico del neonato.

Hyaline membrane disease: the role of ethnicity and maternal risk characteristics.

OBJECTIVE: Our objective was to explore the association between maternal ethnicity and maternal antepartum complications of pregnancy, maternal sociodemographic factors, and newborn characteristics with the incidence of hyaline membrane disease. STUDY DESIGN: By using a retrospective cohort analysis the incidence of hyaline membrane disease was determined for 2295 preterm infants. The study population consisted of all live, inborn infants delivered vaginally from 1982 to 1987. Statistical differences were assessed by use of chi 2 and Student's t tests. A logistic regression procedure determined the relationship of ethnicity and hyaline membrane disease after the study was controlled for all other significant population differences. RESULTS: The differences between black and white populations in marital status, were statistically significant years of education, prolonged rupture of membranes, anemia, and chronic hypertension were statistically significant. Infants of black mothers were diagnosed with hyaline membrane disease less often than infants of white mothers (overall and at each gestational age interval). After the study was controlled for population differences, infants of black mothers were still found to experience hyaline membrane disease less often. CONCLUSION: These data suggest that hyaline membrane disease occurs less frequently, is less severe, and is accompanied by fewer related complications in black preterm infants.

Prematurity and the developing lung.

Bronchopulmonary dysplasia results from treatment of immature lungs resulting from an abnormally short gestation or from pulmonary hypoplasia. Lung hypoplasia secondary to lung compression, oligohydramnios, or diminished complexity of tissue. Normal lung development and the pathologic process associated with lung hypoplasia and their effects of postnatal lung structure are reviewed.

The relationship of fluid restriction during the 1st month of life to the occurrence and severity of bronchopulmonary dysplasia in low birth weight infants: a 1-year radiological follow up.

One hundred consecutive low birth weight (LBW) infants (less than 1751 g) were randomized into a study group having a restricted fluid intake until 4 weeks of age and a control group following the fluid regimen conventionally used in the hospital. Chest X-ray films were examined on admission, at the ages of 3 days, 7 days, 2 weeks and 4 weeks and at 2-monthly visits to the outpatient clinic up to 1 year of age or until the chest examinations were normal. The severity of hyaline membrane disease (HMD) and typical radiological abnormalities of bronchopulmonary dysplasia (BPD) were assessed. Twelve patients succumbed, one in the study group and 11 in the control group. The study group seemed experience less severe HMD than the controls. Fifty-four percent of the former and 32% of the latter were alive and had no radiological signs of BPD at 4 weeks of age (P less than 0.05). The difference between the groups in the cumulative number of normal chest X-ray examinations during the follow up was even more significant. The percentage of normal X-ray films at 1 year of age was 92% in the study group and 72% in the control group. These results suggest that fluid restriction for the first 4 weeks of life can lower the incidence of radiological abnormalities typical of BPD obtained during the 1st year of life in LBW infants. Pulmonary oedema seems to be a significant aetiological factor causing HMD to develop into chronic lung disease.

Uma análise da relaçäo entre a via do parto, complicaçöes obstétricas e a doença da membrana hialina / An analysis of relationship between the delivery way, obstetric complications and hyaline membrane disease

Em vista da controvérsia atual sobre a influência da rota do parto na incidência da Doença da Membrana Hialina, decidi investigar, através da análise retrospectiva de 82 casos ocorridos no Hospital Säo Lucas da PUC entre janeiro/1981 e junho/1988, a relaçäo desta entidade com a via do parto e complicaçöes obstétricas associadas. Constatou-se a incidência desta doença em 51 casos (70,83%) quando o parto foi via alta, sendo que o sofrimento fetal foi, em 30% das vezes, a indicaçäo mais freqüente. Näo houve diferença no grau de asfixia entre as duas vias de parto. Näo foi possível avaliar a influência da eletividade do parto como fator causal para Doença da Membrana Hialina. Quanto à gemelaridade, o segundo gêmeo era o único fator independente de risco, mas somente em partos vaginais

Hyaline membrane disease and surfactant protein, SAP-35, in diabetes in pregnancy.

Surfactant-associated protein of Mr 28,000 to 35,000 (SAP-35) is an abundant glycoprotein present in the alveolus of the lung, which imparts both structural organization to surfactant phospholipids and provides regulatory information controlling surfactant phospholipid secretion and metabolism. SAP-35 expression is enhanced by 3'-5'-cyclic adenosine monophosphate and epidermal growth factor during perinatal differentiation of type II epithelial cells. Its synthesis and RNA are also controlled by a variety of inhibitory factors, which include transforming growth factor and insulin. Glucocorticoids both enhance and inhibit SAP-35 expression in fetal lung explants. There is evidence that fetal hyperinsulinemia or hyperglycemia, or both, inhibit the morphologic differentiation of the type II epithelial cell in association with decreased phospholipid surfactant synthesis or secretion. Insulin is also a potent inhibitor of SAP-35 expression in fetal lung tissue, and decreased SAP-35 was previously noted in amniotic fluid of patients with diabetes during pregnancy. Recent progress in the management of diabetes in pregnancy, characterized by more rigorous metabolic control, has decreased the risk of hyaline membrane disease for the infant of the diabetic mother and is associated with normal levels of SAP-35 in amniotic fluid. Hyaline membrane disease remains a major cause of morbidity in infants of diabetic mothers but may also reflect a higher incidence of premature delivery, cesarean section, and asphyxia at delivery as well as inhibition of pulmonary surfactant phospholipid synthesis or expression of the surfactant protein SAP-35.

Prematuridade iatrogênica: aspectos neonatais / Iatrogenic prematurity: neonatal aspects

As relaçöes das características clínicas do recém-nascido portador de prematuridade iatrogênica com os procedimentos médicos säo de difícil interpretaçäo. Sobressai, na literatura, a idéia de que a cesárea, na ausência de trabalho de parto, seria um fator na gênese da doença de membranas hialinas. Parece claro, porém, que em geral, nesses casos, se está lidando com portadores de pulmäo imaturo e que esta condiçäo seria a determinante real do problema respiratório. A anoxia e o sangramento, juntamente com a imaturidade, säo fatores predisponentes que muitas vezes acompanham a cesárea, de um modo geral, marcando-a como um evento a preceder o sofrimento respiratório, sem ter necessariamente nenhuma conotaçäo etiológica. Näo parece possível dizer, no momento, qual o papel verdadeiro da cesárea eletiva na doença de membranas hialinas. Em relaçäo à taquipnéia transitória neonatal, parece provável que seja influenciada pela cesárea, na medida em que esta propicia uma relaçäo diminuída volume aéreo/volume líquido nas vias aéreas, nos primeiros momentos da vida. Mesmo esta noçäo, porém, necessita reavaliaçäo. A inter-relaçäo cesárea/trabalho de parto/anoxia e sangramento/imaturidade pulmonar necessita ser mais profundamente analisada, em sua possível influência sobre o desconforto respiratório neonatal. Desde já um grande problema se coloca para essa análise: a dificuldade que freqüentemente existe no diagnóstico preciso dos quadros de desconforto respiratório neonatal precoce

Hérnia diafragmática à direita em um paciente com membrana hialina: diagnóstico evolutivo; relato de caso / Right diaphragmatic hernia in a patient with hyaline membrane: evolutive diagnosis; a case report

É relatado um caso de hérnia diafragmática direita em um RN pré-termo que desenvolveu membrana hialina nas primeiras horas de vida e, quando da resoluçäo desta, iniciou uma ascensäo hepática pelo forame de Bochdalek, com traduçäo clínica de um distress respiratório e radiográfico de um derrame pleural. Esta migraçäo tardia é atribuida à existência de uma pressäo positiva intratorácica que manteve o fígado em sua posiçäo anatômica até a retirada da assistência ventilatória (CPAP nasal), quando ocorreu uma queda dos níveis pressóricos e a diminuiçäo da resistência pulmonar

Respiratory distress following elective repeat cesarean section.

The clinical course and chest radiographs of 47 infants with respiratory distress after elective cesarean section were reviewed. The mean difference between the gestational age determined prenatally and that postnatally was 2.6 +/- 1.6 weeks. However, 14 of the infants were delivered at term. All 47 infants required more than 40% oxygen, and 18 infants required a respirator. Fifteen infants developed a pneumothorax; one, a pneumopericardium; one, bronchopulmonary dysplasia; and one infant died. Chest radiographs and the clinical course were consistent with hyaline membrane disease in 17 patients; respiratory distress syndrome type II in 24; and in three the radiographic findings were normal. These data suggest that some of the respiratory morbidity subsequent to elective repeat cesarean section is not secondary to iatrogenic delivery of a premature infant, and that much of it is not due to hyaline membrane disease. These data emphasize that respiratory distress in an infant delivered by elective cesarean section does not necessarily suggest poor prenatal care in regard to the timing of delivery.