Mortalidad en prematuros tratados con surfactante exógeno / Mortality in premature infants treated with exogenous surfactant

Objective: Characterize mortality and associated factors in Chilean prematures born < 32 weeks of gestational age (GA) and treated with exogenous surfactant. Method: Cohort of newborns (n = 2 868) registered between 1998-2005 in the database of the Surfactant National Program. The association of gestational and neonatal variables with mortality was estimated through survival analysis and logistic regression. Results: Global mortality was 35 percent, varying by GA from 86.7 percent (< 25 weeks) to 12.6 percent (32 weeks). There was a clear decrease of mortality during the study period, along with a fall in the gestational age and birth weight (BW) of the patients who died (1 021 g +/- 295 to 854 g +/- 258) and GA (27.7 +/- 2.1 to 26.5 +/- 23) during this period. Pulmonary hemorrhage (PH) was the most important factor associated to mortality, so we decided to stratify the analysis by this condition. In children with PH, the mortality estimated risk lower as the GA increased (OR= 0.73; CI95 0.57-0.93) and every 100 g of additional BW (OR= 0.74; CI95 0.63-0.88). Children not affected by PH also had their OR diminished with major GA (OR= 0.82; CI95 0.76-0.90) and more BW (OR= 0.84; CI95 0.79 - 0.89). In addition, the OR decreased with better Apgar 5 min score (OR= 0.80; CI95 0.75-0.85), use of prenatal corticoids (OR= 0.71; CI95 0.56-0.90) and was higher in boys (OR= 1.36; CI95 1.08-1.71). Conclusions: Mortality in premature newborns decreased 15 percent during this period. Inmaturity and extreme low birth weight factors constitute a challenge to improve survival and avoid further complications like PH.

Objetivo: Caracterizar la mortalidad y factores asociados en prematuros chilenos < 32 semanas de edad gestacional (EG) receptores de surfactante exógeno. Pacientes y Métodos: Cohorte de neonatos 1998-2005 (n = 2 868) de la base de datos del Programa Nacional de Surfactante. Se estimó la mortalidad y su relación con variables maternas, del embarazo y neonatales mediante análisis de sobrevida y regresión logística. Resultados: La mortalidad global fue 35 por ciento, variando por EG entre 86,7 por ciento (< 25 semanas) y 12,6 por ciento (32 semanas). La mortalidad descendió en el período, reduciéndose también el peso de nacimiento (PN) de los fallecidos (1 02 lg +/- 295 a 854 g +/- 258) y su EG (27,7 +/- 2,1 a 26,5 +/- 2,3). La hemorragia pulmonar (HP) fue el factor más importante asociado a mortalidad, por lo que se estratificó el análisis por esa condición. En niños con HP, cada semana adicional de EG disminuye el riesgo de morir (OR: 0,73; IC95 0,57-0,93), así como por cada 100 g de peso adicional (OR: 0,74; IC95 0,63-0,88). Sin HP, el riesgo disminuye con mayor EG (OR: 0,82; IC95 0,76-0,90), mayor PN (OR: 0,84; IC95 0,79-0,89), mejor puntuación Apgar 5 minutos (OR: 0,80; IC95 0,75-0,85) y uso de corticoide prenatal (OR: 0,71; IC95 0,56-0,90), siendo significativamente mayor en varones (OR: 1,36; IC(95)1,08-1,71). Conclusiones: En el período, la mortalidad en prematuros disminuyó en 15 por ciento. La inmadurez y extremo bajo peso de niños actualmente viables, plantean importantes desafíos para mejorar su sobrevida y evitar complicaciones, entre ellas, la HP.

Cintigrafía tiroídea (CT) con Tc99m-pertecnectato en recién nacidos (RN) con hipotiroidismo congénito (HC) / Tc99m-pertechnetate thyroid scintigraphy in newborns with congenital hypothyroidism

Background: Congenital hypothyroidism is one of the most frequent endocrine diseases of the newborn and requires an early diagnosis to avoid its deleterious effects on neurological and intellectual functions. Aim: To evaluate thyroid scintigraphy (TS) findings in newborns with congenital hypothyroidism (CH), detected in the national program of newborn screening, which is working in Chile since 1992. Material and methods : TS findings of 189 newborns with CH (68 percent female) were analyzed. Tc99m pertechnetate TS was performed at 19 ñ 11 days of life. The gland was classified as eutopic, ectopic or absence of contrast (AC). Eutopic glands were classified by visual and quantitative criteria as: normal, goiter and decreased contrast (DC). TS results were compared by gender and hormonal levels. Results: Forty seven percent of newborns had ectopy, 29.1 percent eutopy and 24.3 percent AC. Eutopic gland predominated in males (44.2 percent vs 22.7 percent) and ectopy was more frequent in girls (53.1 percent vs 32.8 percent, p <0.05). Newborns with AC had the most severe hormonal alterations, without gender differences. Newborns with normal TS had less hormonal alterations than those with goiter. Conclusions: TS allows an etiological classification of CH. Thyroid dysgenesis is the most frequent cause, most of which correspond to ectopy, especially in girls. Eutopic glands are present in one third of newborns with CH. Goiter predominates, especially in males