Mode of delivery and antenatal steroids and their association with survival and severe intraventricular hemorrhage in very low birth weight infants.

OBJECTIVE: To determine whether CS delivery and receipt of antenatal steroids (ANS) in vertex-presenting singletons with a gestational age (GA) between 24 and 30 weeks is associated with improved survival and improved severe intraventricular hemorrhage (sIVH)-free survival. STUDY DESIGN: Multicenter cohort, retrospective analysis of prospectively collected data. Vertex-presenting singletons newborns with GA 24 to 30 weeks, birth weight between 500 and 1500 g, without major congenital malformations, born between 2001 and 2011 at Neocosur centers were included. RESULTS: Four thousand three hundred and eighty-six infants fulfilled inclusion criteria: 45.8% were delivered vaginally and 54.2% by cesarean section (CS). Newborns delivered vaginally received less ANS, had lower GA, Apgar scores and a lower incidence of survival and sIVH-free survival (P<0.001). Newborns with better survival were those with ANS, independent of mode of delivery. At 24 to 25 weeks GA, increased survival and sIVH-free survival were associated with ANS and CS delivery, compared with those who received ANS and delivered vaginally. CONCLUSIONS: Among vertex-presenting singletons with GA 24 to 30 weeks, better survival and IVH-free survival were associated with ANS, independent of mode of delivery. In infants at 24 to 25 weeks gestation the combination of ANS/CS was associated with improvement in both outcomes.

Humanitarian military medical mission in a postconflict environment: lessons from Cambodia.

In the aftermath of a genocidal civil war, the Government of Cambodia is left with major deficiencies in its healthcare system. This article recounts a military medical mission to Cambodia; the authors describe the objectives of the mission and provide a summary of the lessons learned. Specific areas of concern include healthcare infrastructure, logistics, standards of care, social traditions, organizational issues and potential problems in civil-military collaboration. This report is offered as a heuristic device to illuminate some of the issues that can mediate the success of military medical missions in postconflict environments.

Prevalencia al nacimiento de aberraciones cromosómicas en el Hospital Clínico de la Universidad de Chile. Período 1990-2001 / Prevalence of chromosomal aberrations at birth in the Clinical Hospital of Universidad de Chile, 1990-2001

BACKGROUND: A cytogenetical study should be performed to every newborn with malformations. If a chromosomal aberration is found, parents must be studied to give an adequate genetic advise. AIM: To study the frequency of chromosomal aberrations in newborns with malformations. PATIENTS AND METHODS: In the Clinical Hospital of the University of Chile all malformations in newborns are registered, as part of the Collaborative Latin American Study of Congenital Malformations (ECLAMC). The frequency of chromosomal aberrations, determined by cytogenetical studies, was determined in newborns with malformations. RESULTS: In the study period, there were 32,214 births. Of these, 2,268 live newborns and 43 stillbirths had malformations. Ninety nine children with malformations had chromosomal aberrations (4.3 per cent). Trisomy 21 was the most common aberration with a rate of 23/10,000 births, followed by trisomy 18 with a rate of 4/10,000 and trisomy 18 with a rate of 1.2/10,000. Ninety four percent of these children were born alive and 16.1 per cent died before discharge from the hospital. The masculinity indexes for Down syndrome and for trisomy 18 were 0.38 and 0.61 respectively. CONCLUSIONS: A higher frequency of female gender for trisomy 21 and male gender for trisomy 18 has not been reported previously.

Sobrevida, viabilidad y pronóstico del prematuro / Survival, viability and prognosis of premature infant

An heterogeneous group of newborns with different gestational ages, birth weight, nutritional status and different risks of morbidity and mortality are classified as premature. Therefore the definition of premature children subgroups is mandatory. Very low weight premature babies are those with a birth weight of less than 1500 g. In Chile, they correspond to 0.9 per cent of newborns and they contribute to neonatal mortality with 50 to 70 per cent and to infantile mortality, with 25 to 30 per cent. Survival of extremely premature babies has improved significantly in the last decades, due to a better perinatal care, the appearance of neonatal intensive care units, the routine use of mechanical ventilation, the perinatal use of steroids and the introduction of exogenous surfactant. However, survival varies considerably according to the place of birth, birth weight and gestational age and may be associated with different degrees of physical and mental disability. The imminent birth of a child in the limit of viability will require complex and difficult ethical decisions. There is consensus that the limit of viability is 23 weeks and that it fluctuates between 24 and 26 weeks in different parts of the world.

Test de Apgar. Después de medio siglo. Sigue vigente? / The Apgar Score. Is it still valid after a half century?

In 1952, Virginia Apgar MD, proposed to assess the clinical condition of newborns, during the first minutes of life and to evaluate anesthetic and obstetrical practices. She proposed five objectives and easily measured clinical signs: cardiac frequency, respiratory effort, muscle tone, irritability and color. The test was later named Apgar Score Test. Since then, all newborns are evaluated using Apgar score. This article reviews the uses and abuses of Apgar test. It has been used to assess asphyxia, predict neurological damage, to identify newborns that require reanimation and as a survival predictor. It is concluded that Apgar score is useful to know the vitality of a newborn during his first minutes of life. It is a background, that along with acid base state and evolution, allows the diagnosis of asphyxia and predicts survival. Therefore, after half a century of use, it still remains useful.

[Ambiguous sex: prevalence at birth in the maternity ward of the clinical hospital of the university of Chile]. / Sexo ambiguo: prevalencia al nacimiento en la maternidad del Hospital Clínico de la Universidad de Chile.

BACKGROUND: Ambiguous sex has a great phenotypic variability and is a serious medical and social problem. AIM: To study the prevalence of ambiguous sex among newborns. MATERIAL AND METHODS: As part of the ECLAMC (Cooperative Latin American Study of Congenital Malformations) all newborns with malformations are registered and the next normal newborn is considered as a control. RESULTS: 50.253 births occurred (between 1982 and 1999) in the University of Chile Maternity Hospital. The rate of congenital malformations was 6.78% and the prevalence of ambiguous sex was 4.7 per 10.000 births. Affected children had a lower birth weight, lower gestational age and a lower maternal age than controls. The most frequent associated malformations were of the urinary (64%) and cardiovascular systems (60.7%). Thirty two percent of affected children had specific syndromes. CONCLUSIONS: The prevalence of ambiguous sex in this study was 4.7 per 10.000 births, which is higher than that reported in the ECLAMC (1.9 per 10,000).

[Incidence of the cleft lip and palate in the University of Chile Maternity Hospital and in maternity Chilean participating in the Latin American Collaborative Study of Congenital Malformations (ECLAMC)]. / Incidencia de labio leporino y paladar hendido en la Maternidad del Hospital Clínico de la Universidad de Chile y en las maternidades chilenas participantes en el estudio colaborativo Latino Americano de malformaciones congénitas (ECLAMC) período 1991-1999.

BACKGROUND: ECLAMC is a registry, aimed to assess the incidence of congenital malformations, that started in 1967 and Chile incorporated to it in 1969. AIM: To report the incidence of cleft lip/palate, updated to 1999 in the University of Chile Maternity Hospital and other Chilean hospitals participating in the ECLAMC. PATIENTS AND METHODS: A review of the ECLAMC database that registers all births or stillbirths of more than 500 g. RESULTS: The incidence of orofacial cleft, at the University of Chile Maternity Hospital, in the period 1991-1999 was 17.8 per 10,000 (12.6 for cleft lip and 5.2 for cleft palate). The incidence in the rest of participating hospitals was 12.04 and 4.6 respectively. Males had a higher incidence of cleft lip and 80% of children with cleft palate, had other malformations, most of them as part of a syndrome (13 and 18 trisomy, holoproscencephalia, Pierre Robin, Apert en EE syndromes, anencephaly etc). In three of 12 children with cleft lip but without cleft palate, there was a relative with the same malformation. CONCLUSIONS: It is proposed that both entities, cleft lip with or without cleft palate and cleft palate without cleft lip, are two etiopathogenically different conditions.

[Anorectal congenital malformations and their preferential associations. Experience of the Clinical Hospital of the University of Chile. Period 1979-1999]. / Malformaciones congénitas anorrectales y sus asociaciones preferentes. Experiencia del Hospital Clínico de la Universidad de Chile. Período 1979-1999.

BACKGROUND: Anorectal atresia is a relatively frequent malformation in the newborn. According to the Latin American Collaborative Study for Congenital Malformations (ECLAMC), its frequency is 4.1 per 10,000 born alive. AIM: To determine the frequency of anorectal malformations at birth, and compare the figures with those of other maternity hospitals in Chile participating in ECLAMC, with the figures of the whole ECLAMC and with figures from other worldwide monitoring systems. PATIENTS AND METHODS: All births occurred in the University of Chile Clinical Hospital between January 1979 and August 1999, were reviewed. RESULTS: During the study period, 70,242 children were born, 4,486 had a malformation and 54 had an anorectal malformation (7.7 per 10,000 born alive). Fifty nine percent had other associated malformations (of the urinary tract in 42.5%, skeletal in 26% and cardiovascular in 18.5%). Five stillborn babies had other severe malformations. Twenty one children had a fistula. Forty three % were male, 39% female and 18% had ambiguous sex. When compared with normal controls, malformed newborns had a lower birth weight, lower gestational age and a higher mean maternal age, a higher frequency of metrorrhagia during the first trimester of pregnancy, a higher number of siblings with malformations and a higher degree of consanguinity among parents. CONCLUSIONS: The participation of recessive genes in the etiology of anorectal malformations is suggested.

[Esophageal atresia and associated malformations]. / Atresia esofágica y malformaciones asociadas.

BACKGROUND: Survival of newborns with esophageal atresia and tracheoesophageal fistula has increased in the last years. AIM: To assess the prevalence of esophageal atresia and describe associated malformations in Chilean newborns. MATERIAL AND METHODS: All births occurring between January 1983 and June 1998 were studied. All malformed children were registered and the next non malformed born child was considered as control. RESULTS: During the study period, 50,965 births occurred and 3,336 malformed children were born. Eighteen (3 stillborn) had esophageal atresia with a rate of 3,53 per 10,000 born alive. Overall survival was 73%. Survival among children classified in Waterson groups A and B was 100% and 50% among those classified in group C. Seventy two percent had associated malformations, being congenital cardiopathies and skeletal malformations the most frequent. VACTERL association was found in 44% of children. All stillborn children had other severe malformations. When compared to controls, malformed children had a lower weight, a lower gestational age, their mothers had a higher age, a higher frequency of relatives with malformations and a higher frequency of maternal diseases during the first trimester of pregnancy. CONCLUSIONS: The rate of esophageal atresia found in this study is similar to that reported in other Chilean obstetrical units as part of the Latin American Study of Congenital Malformations (ECLAMC).

[Dual photon absorptiometry in full-term newborns]. / Densitometría bifotónica en recién nacidos de término.

BACKGROUND: There is scanty information about bone mineral density in newborns. Normal values are needed to assess the effects of diseases and drugs used during the neonatal period. AIM: To assess bone mineral density in normal newborns. PATIENTS AND METHODS: Total body bone mineral density was measured in 16 newborns with 39 +/- 1.2 weeks of gestational age, using a Norland dual photon densitometer. RESULTS: The mean weight of newborns was 3.366 +/- 325 g. Bone mineral content was 58.3 +/- 10.8 g and bone mineral density was 0.369 +/- 9.6 g/cm2. RESULTS: The availability of normal bone mineral content values in newborns will be useful for the assessment of conditions that affect bone mineralisation.

The effect of early dexamethasone administration on bronchopulmonary dysplasia in preterm infants with respiratory distress syndrome.

OBJECTIVES: This study was carried to evaluate the effect of early administration of dexamethasone on the incidence of bronchopulmonary dysplasia (BPD) and/or death in surfactant-treated preterm infants with respiratory distress syndrome (RDS). STUDY DESIGN: In a multicenter, double-blind, placebo-controlled trial, 109 preterm infants with RDS and birth weights between 700 and 1600 gm, who were treated with mechanical ventilation and surfactant, were randomly assigned before 36 hours of life to receive dexamethasone (n = 55) or placebo (n = 54) for 12 days. RESULTS: There were no differences in the incidence of BPD and/or death between groups. However, fewer patients in the dexamethasone group were oxygen-dependent at 36 weeks after conception (8% vs 33%, p < 0.05). The dexamethasone group had a lower incidence of necrotizing enterocolitis (0% vs 9%, p < 0.05). The incidence of arterial hypertension, hyperglycemia, and sepsis was not affected by the treatment. Basal and poststimulation serum cortisol levels did not differ between groups. CONCLUSION: The administration of dexamethasone early in the course of RDS does not decrease the incidence of BPD and/or death in preterm infants. However, dexamethasone may reduce oxygen dependency at 36 weeks after conception.

[Epidemiologic study of factors associated with hypospadias]. / Estudio epidemiol ogico de factores asociados a hipospadias.

From August 60 to December 90, 103 male newborns with hypospadias were diagnosed among 124 588 consecutive newborns examined (8.3 per 10,000). Mortality among them was 1.94%. The annual incidence rate increased significantly over the study period (p < 0.001. Hypospadias was an isolated finding in 92% of cases, and its was associated to other non genital malformation in 8.7%. Location of hypospadias was distal in 73% and proximal in 15.5%. There was no seasonal variation in the incidence rate. Weight of affected individuals did not differ from that of controls. Older age of parents among affected individuals was not statistically significant.

[Increase of incidence of Down syndrome and its possible relation with increased maternal age]. / Aumento de la incidencia del síndrome de Down y su posible relación con el incremento de la edad materna.

Among 47,458 consecutive births taking place between july 1977 and december 1989, we found 83 newborns with Down syndrome, for a 1.74/1000 live births incidence rate. This compares to a rate of 1.39 rate observed at the same maternity from 1971 to 1977 (NS). The mean age of all mothers was 25.9 years as compared to 31.87 for mothers of children with Down syndrome (p < 0.00001). The mean maternal age has increased from 24.34 in 1977 to 27.38 in 1988 (p < 0.0001), mostly due to a greater proportion of the 25 to 29 year-old group of mothers. These data support, although not conclusively, that the increased incidence of Down syndrome in our population is related to older maternal age.

[Incidence of malformations of the central nervous system: 1978-1988]. / Incidencia de las malformaciones del sistema nervioso central: período 1978-1988.

During the period Jan 1978 to Dec 1988, 41,867 deliveries took place at the University of Chile Hospital. Among them, 148 babies were found to have malformations of the central nervous system, an incidence of 3.6 per 1000 live births. A longitudinal study from 1969 to 1988 suggests a yearly increment of 0.1% in the incidence rate of these malformations. The comparison of some quantitative variables, such as gestational age, birthweight, number of previous abortions and some risk factors like maternal illness, bleeding, radiation exposure, drug ingestion during the first trimester of pregnancy and instructional level of both parents show significant differences between the malformed and the control newborns. No significant differences were found for maternal age, sex nor seasonal variation.

Synthesis of sulfated glycosaminoglycans by the three cell types of the rabbit cornea in culture.

Rabbit corneal cells were cultivated for 21 days and then exposed to Na235SO4, a precursor of sulfated glycosaminoglycans (GAG). All 3 cell types of the cornea, the fibroblasts, the epithelial as well as the endothelial cells, synthesize GAG. The fractionation-patterns of the epithelial and endotherlial GAG are almost identical and differ clearly from the one of fibroblastic GAG.

Biosynthesis of glycosaminoglycans by mammalian corneal epithelium and fibroblasts in vitro. II. Approach to specify the GAG from the two cell types.

35S- as well as 3H-labeled glycosaminoglycans (GAG) produced by cultivated epithelium and fibroblasts of the rabbit cornea were treated with testicular hyaluronidase, leech hyaluronidase and chondroitinase-ABC or -AC. The fractionation-patterns of enzyme-treated GAG were compared with blanks not exposed to enzymes. The epithelial GAG revealed to be generally more resistant to the enzymatic degradation than the GAG synthesized by the fibroblasts, but--depending on the enzyme--in the GAG of both cell types the same fractions were attacked. The decline of the radioactivity in the fractions of enzyme-treated GAG allows the conclusions that both cell types produce relatively small amount of keratan sulfate but mainly chondroitin sulfates with a different degree of sulfation. In addition GAG, not present in the normal cornea, are synthesized: hyaluronic acid chiefly by fibroblasts and probably dermatan sulfate. The possible role of the fibroblastic and epithelial GAG in corneal wound repair is discussed.

Biosynthesis of glycosaminoglycans by mammalian corneal epithelium and fibroblasts in vitro. I. Isolation and fractionation-differences of GAG from the two cell types.

Labeled glycosaminoglycans (GAG) were isolated and fractionated from cultured rabbit corneal epithelium, rabbit or bovine corneal fibroblasts and rabbit bone fibroblasts that had been previously incubated with either Na235SO4 or D-glucosamine-6-3H precursors. Thus it was demonstrated that the epithelium produces GAG. The fractionations indicated that the epithelial cells predominantly synthesize GAG with a lower degree of sulfation than those produced by corneal fibroblasts. The GAG-fractionation-patterns of the corneal epithelium and bone fibroblasts were similar.