Physiology of transition from intrauterine to extrauterine life

Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, 3333 Burnet Avenue, ML#7029, Cincinnati, OH 45229-3039, USA.
Clinics in perinatology (Impact Factor: 2.13). 12/2012; 39(4):769-83. DOI: 10.1016/j.clp.2012.09.009
Source: PubMed

ABSTRACT The transition from fetus to newborn is the most complex adaptation that occurs in human experience. Lung adaptation requires coordinated clearance of fetal lung fluid, surfactant secretion, and onset of consistent breathing. The cardiovascular response requires striking changes in blood flow, pressures, and pulmonary vasodilation. Energy metabolism and thermoregulation must be quickly controlled. The primary mediators that prepare the fetus for birth and support the multiorgan transition are cortisol and catecholamine. Abnormalities in adaptation are frequently found following preterm birth or cesarean delivery at term, and many of these infants need delivery room resuscitation to assist in this transition.

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    • "Altogether these factors will predispose preterm infants to respiratory insufficiency and the need for positive pressure ventilation and oxygen supplementation. In this scenario, the achievement of a stable pre-ductal SpO 2 is substantially delayed even in healthy well-adapted preterm infants [10] [37]. Recently, a group of researchers developed a SpO 2 reference range for the first ten minutes after birth for term and preterm infants who did not receive any medical intervention in the delivery room. "
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  • NeoReviews 06/2012; 13(6):e334-e335. DOI:10.1542/neo.13-6-e334
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