Prominence of cerebral veins using susceptibility weighted magnetic resonance imaging (SWI) has been used as a qualitative indicator of cerebral venous oxygenation (CvO). Quantitative susceptibility mapping (QSM) adds more precision to the assessment of CvO, but has not been applied to neonatal hypoxic ischemic injury (HII). QSM measures of venous susceptibility and their correlation with direct measures of brain oxygenation and cerebral blood flow (CBF) in the neonatal piglet.
View Article and Find Full Text PDFCirculating metabolites of nitric oxide, such as nitrite, iron nitrosyls (FeNO), and nitrosothiols, have vasodilatory bioactivity. In both human and sheep neonates, plasma concentrations of these NO metabolite (NOx) concentrations fall >50% within minutes after birth, raising the possibility that circulating NOx plays a role in maintaining low fetal vascular resistance and in the cardiovascular transition at birth. To test whether the fall in plasma NOx concentrations at birth is due to either ligation of the umbilical cord or oxygenation of the fetus to newborn levels, plasma NOx concentrations were measured during stepwise delivery of near-term fetal lambs.
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