Hemorragia intraventricular en el neonato prematuro / Intraventricular hemorrage in preterm infants

La hemorragia intraventricular (HIV) es la principal complicación neurológica en los prematuros; consiste en sangrado de la matriz germinal y las regiones periventriculares del cerebro. Su frecuencia y gravedad aumentan en la medida en que es menor el peso al nacimiento; se la halla entre 10 y 20 por ciento de los neonatos de 1.000-1.500 gramos y hasta en 70 por ciento en los menores de 700 gramos; se presenta en 85 por ciento de las veces en las primeras 72 horas posparto y en 95 por ciento ya es evidente al finalizar la primera semana; son múltiples los factores maternos y fetales que se han encontrado asociados con el aumento o disminución de su frecuencia, además del uso de algunos medicamentos.Se han propuesto diversos mecanismos fisiopatogénicos asociados a la inmadurez neurológica para explicar la aparición de la HIV.Las manifestaciones clínicas son variables en cuanto a presentación y evolución. La confirmación diagnóstica, la clasificación y el pronóstico se basan en la ecografía transfontanelar.La principal medida preventiva es la disminución de la frecuencia del parto prematuro; los resultados de otras medidas como el uso prenatal y posnatal de algunos medicamentos para evitarla y tratarla han sido variables.El pronóstico depende de la extensión de la hemorragia, del desarrollo de leucomalacia periventricular y del grado de dilatación ventricular.

Neonatal intraventricular hemorrage (IVH) is the main neurological complication in preterm infants involving bleeding into the germinal matrix and the periventricular brain areas. Its incidence and severity are greater with lower birthweigth: from 10-20% in 1.000-1.500 g babies to 70% in those less than 700 g. Most often (85%) it appears during the first 72 hours after birth and almost 95% of the cases are evident by the end of the first week of life. Many maternal and fetal risk factors are associated with the risk of neonatal IVH. Diferent pathogenic mechanisms associated with an immature central nervous system have been proposed to explain IVH. Clinical manifestations and evolution are variable. Transfontanelar cranial ultrasonography permits diagnosis, classification and prognosis of HIV. The main preventive intervention is the reduction of the frequency of preterm delivery; treatment with different drugs before and after delivery to prevent IVH has had variable results. Prognosis depends on the severity of IVH, the development of periventricular leukomalacia and ventriculomegaly.

Detection of Acute Intraventricular Hemorrhage: Comparison of FLAIR MR Imaging with Unenhanced CT

PURPOSE: To compare the usefulness of fluid-attenuated inversion recovery (FLAIR) MR imaging with that of unenhanced CT in the detection of acute intraventricular hemorrhage (IVH). MATERIALS AND METHODS: Thirty-four patients with acute IVH underwent FLAIR MR imaging and unenhanced CT within three days of the onset of symptoms. Except in one patient, all MR studies were performed after CT. The mean time intervals between CT and symptom onset and between CT and MR examinations were six and five hours, respectively. Two radiologists evaluated the detectability and conspicuity of acute IVH at FLAIR MR imaging and unenhanced CT. Positive imaging criteria in the detection of acute IVH were intraventricular hyperintensity at FLAIR MRI and hyperattenuation at CT. RESULTS: Acute IVH was detected in all patients at FLAIR MR imaging and in 30 (88%) of 34 patients at unenhanced CT. In 32 patients (94%), the conspicuity of IVH at FLAIR MR imaging was as good as or better than that at unenhanced CT. CONCLUSION: FLAIR MR imaging was superior to unenhanced CT in the detection of acute IVH.

Predicting Intraventricular Hemorrhage by the Nucleated Erythrocytes Counts in Preterm Neonates

PURPOSE: Prolonged fetal hypoxia stimulates erythropoiesis in fetal life and induces increased nucleated erythrocytes(NRBC) counts at the early newborn period. To evaluate the relationship between prolonged fetal hypoxia and neonatal intraventricular hemorrhage (IVH), and the prediction of neonatal IVH by neonatal NRBC. METHODS: We compared the daily courses of the absolute NRBC count in preterm new- boms at 34 weeks' gestation or earlier with(n=17) and without(n=20) IVH for 7 days of life. RESULTS: Absolute NRBC counts at birth were higher in neonates with IVH than in control neonates(2,499/mm3+/-3,748 and 412/mm3+/-272, respectively, P=0.0022). The cut-off value of 1,000/mm3 for absolute NRBC counts at birth showed the best parameter estimate of the predictive model for IVH at early newborn period with 100% of positive predictive value and 74.1% of negative predictive value. CONCLUSION: Prolonged fetal hypoxia inducing fetal erythropoiesis near labor is closely related to IVH at early newborn period. Thabsolute NRBC counts at birth is the very important predictable marker for the condition.