Hemodynamic and metabolic responses to moderate asphyxia in brain and skeletal muscle of late-gestation fetal sheep

Autor: D Peebles, R. Springett, S. R. G. Harding, Mark A. Hanson, James P. Newman
Rok vydání: 2000
Předmět:
Zdroj: Journal of Applied Physiology. 88:82-90
ISSN: 1522-1601
8750-7587
DOI: 10.1152/jappl.2000.88.1.82
Popis: The purpose of this study was to investigate metabolic and hemodynamic responses in two fetal tissues, hindlimb muscle and brain, to an episode of acute moderate asphyxia. Near-infrared spectroscopy was used to measure changes in total hemoglobin concentration ([tHb]) and the redox state of cytochrome oxidase (COX) simultaneously in the brain and hindlimb of near-term unanesthetized fetal sheep in utero. Oxygen delivery (Do2) to, and consumption (V˙o2) by, each tissue was derived from the arteriovenous difference in oxygen content and blood flow, measured by implanted flow probes. One hour of moderate asphyxia ( n = 11), caused by occlusion of the maternal common internal iliac artery, led to a significant fall in Do2to both tissues and to a significant drop inV˙o2by the head. This was associated with an initial fall in redox state COX in the leg but an increase in the brain. [tHb], and therefore blood volume, fell in the leg and increased in the brain. These data suggest the presence of a fetal metabolic response to hypoxia, which, in the brain, occurs rapidly and could be neuroprotective.
Databáze: OpenAIRE