RESUMEN
The growth of 32 extremely low birth weight infants (1000 gm or less) was determined at adolescence. Their height, weight, and head circumference were measured twice in the first year of life and then at ages 2, 3, 5, 8, 10 years, and during adolescence (12 to 18 years). The mean height, weight, and head circumference of the adolescents were at the 50th percentile. Female heights were > or = their mothers; male heights were in the same or greater percentile than those of their fathers. Extremely low birth weight infants experience "catch-up" growth up to and into adolescence and attain predicted biparental genetic height.
Asunto(s)
Estatura , Peso Corporal , Recién Nacido de muy Bajo Peso/crecimiento & desarrollo , Adolescente , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Trastornos del Crecimiento/diagnóstico , Trastornos del Crecimiento/epidemiología , Cabeza/anatomía & histología , Humanos , Recién Nacido , Estudios Longitudinales , Masculino , Factores de TiempoRESUMEN
OBJECTIVE: To determine whether fetal exposure to cigarette smoke impairs postnatal chemoreceptor control of ventilation and hypercapnic and hypoxic awakening responses. STUDY DESIGN: Smoking (n = 13) and nonsmoking (n = 34) women were recruited during pregnancy. Serum cotinine levels were measured to assess level of nicotine exposure. The infants were studied at 2 to 3 months of age for ventilatory and awakening responses to hypoxia (17%, 15% and 13% inspired O2) and hypercapnia 4%, 6%, and 8% inspired CO2). Continuous measures were analyzed with unpaired t tests and analysis of variance for repeated measures. Proportions of awakening and periodic breathing were analyzed by means of a comparison of proportions. RESULTS: The infants of smokers had lower birth weights (3022 +/- 566 vs 3518 +/- 491 gm; p < or = 0.005) and were older at the time of study (10.4 +/- 2.8 vs 8.7 +/- 1.3 weeks; p < 0.01) than the control infants. Maternal cotinine levels were higher in smokers (97.8 +/- 107 ng/ml vs no cotinine; p < 0.0001). More infants of smokers failed to awaken with hypoxia than did control infants (54% vs 15%; p = 0.006). The ventilatory responses to hypoxia and hypercapnia were similar in the two groups. All infants awakened with hypercapnia, and there was no difference in the awakening threshold for carbon dioxide (50.3 +/- 4.5 vs 48.3 +/- 5.4 mm Hg; p = 0.28). CONCLUSION: Infants of mothers who smoked during pregnancy have deficient hypoxic awakening responses, which may contribute to the increased risk of sudden infant death syndrome in infants of smoking mothers.
Asunto(s)
Hipoxia/fisiopatología , Efectos Tardíos de la Exposición Prenatal , Muerte Súbita del Lactante/etiología , Contaminación por Humo de Tabaco/efectos adversos , Vigilia , Adulto , Análisis de Varianza , Femenino , Humanos , Hipercapnia/fisiopatología , Lactante , Masculino , Embarazo , Pruebas de Función Respiratoria/métodos , Pruebas de Función Respiratoria/estadística & datos numéricos , Contaminación por Humo de Tabaco/estadística & datos numéricosRESUMEN
During the double-blind, multicenter trials of the synthetic surfactant Exosurf Neonatal, we measured pulmonary mechanics at 28 days of age in 30 surfactant- or placebo-treated infants. In the 20 surfactant-treated and 10 air-treated infants studied, there were no differences in lung compliance or resistance at 28 days of age. These observations suggest that improvements in pulmonary function reported early in the neonatal course after the administration of exogenous surfactant are not detectable at 28 days of age.