The fetal brain sparing response to hypoxia: physiological mechanisms
TLDR
In this paper, it was shown that major components of fetal brain sparing during acute hypoxia are triggered exclusively by a carotid chemoreflex and that they are modified by endocrine agents and vascular oxidant tone.Abstract:Â
How the fetus withstands an environment of reduced oxygenation during life in the womb has been a vibrant area of research since this field was introduced by Joseph Barcroft, a century ago. Studies spanning five decades have since used the chronically instrumented fetal sheep preparation to investigate the fetal compensatory responses to hypoxia. This defence is contingent on the fetal cardiovascular system, which in late gestation adopts strategies to decrease oxygen consumption and redistribute the cardiac output away from peripheral vascular beds and towards essential circulations, such as those perfusing the brain. The introduction of simultaneous measurement of blood flow in the fetal carotid and femoral circulations by ultrasonic transducers has permitted investigation of the dynamics of the fetal brain sparing response for the first time. Now we know that major components of fetal brain sparing during acute hypoxia are triggered exclusively by a carotid chemoreflex and that they are modified by endocrine agents and the recently discovered vascular oxidant tone. The latter is determined by the interaction between nitric oxide and reactive oxygen species. The fetal brain sparing response matures as the fetus approaches term, in association with the prepartum increase in fetal plasma cortisol, and treatment of the preterm fetus with clinically relevant doses of synthetic steroids mimics this maturation. Despite intense interest into how the fetal brain sparing response may be affected by adverse intrauterine conditions, this area of research has been comparatively scant, but it is likely to take centre stage in the near future.read more
Citations
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Neonatal Morbidities of Fetal Growth Restriction: Pathophysiology and Impact.
Atul Malhotra,Beth J. Allison,Margie Castillo-Melendez,Margie Castillo-Melendez,Graham Jenkin,Graham Jenkin,Graeme R. Polglase,Graeme R. Polglase,Suzanne L. Miller,Suzanne L. Miller +9 more
TL;DR: A better understanding of neonatal morbidities associated with FGR will enable early neonatal detection, monitoring and management of potential adverse outcomes in the newborn period and beyond.
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Diagnostic Value of Blood Sampling in Fetuses With Growth Retardation
Giorgio Pardi,Irene Cetin,Anna Maria Marconi,A. Lanfranchi,Patrizia Bozzetti,Enrico Ferrazzi,Mauro Buscaglia,Frederick C. Battaglia +7 more
TL;DR: Assessment of fetal oxygenation and acid-base balance is not indicated in fetuses with growth retardation if their heart rates and the results of velocimetry are normal, but fetal-blood sampling can distinguish fetuses that have growth retardations alone from those that also have hypoxia and acidosis, and thus may aid in determining the optimal time of delivery.
Journal ArticleDOI
Gestational Hypoxia and Developmental Plasticity
TL;DR: This review explores the impact of gestational hypoxia on maternal health and fetal development, and epigenetic mechanisms of developmental plasticity with emphasis on the uteroplacental circulation, heart development, cerebral circulation, pulmonaryDevelopment, and the hypothalamic-pituitary-adrenal axis and adipose tissue.
Journal ArticleDOI
Brain Injury and Neurodevelopmental Outcome in Congenital Heart Disease: A Systematic Review
TL;DR: Prenatal and postnatal preoperative abnormal cerebral findings might play an important role in neurodevelopmental impairment in infants with CHD, and increased awareness of the vulnerability of the young developing brain of an infant withCHD among caregivers is essential.
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Improving pregnancy outcomes in humans through studies in sheep
Janna L. Morrison,Mary J. Berry,Kimberley J. Botting,Jack R. T. Darby,Martin G. Frasch,Kathryn L. Gatford,Dino A. Giussani,Clint Gray,Richard Harding,Emilio A. Herrera,Matthew W. Kemp,Mitchell C. Lock,I. Caroline McMillen,Timothy J. M. Moss,Gabrielle C. Musk,Mark H. Oliver,Timothy R. H. Regnault,Claire T. Roberts,Jia Yin Soo,Ross L. Tellam +19 more
TL;DR: The aim of this review is to highlight the advances in perinatal human medicine that have been achieved following translation of research using the pregnant sheep and fetus.
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