Fetal Hemodynamic Alterations During Advancing Gestation
Since oxygenation for the fetus occurs in the placenta the fetal circulation is arranged so that several sites of shunting are present. In addition, preferential flow and streaming take place to offset the disadvantages of intermixing of oxygenated and deoxygenated blood returning through the venous circulations. In the presence of fetal stress these patterns are changed, and the distribution of blood flow to different organs is modified. Since individual organ blood flows normally change as gestation advances an understanding and knowledge of these changes is important when considering circulatory alterations invoked by stress.
KeywordsCardiac Output Fetal Lamb Ventricular Output Newborn Lamb Fetal Heart Rate Monitoring
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