Measurement of umbilical arterial blood flow to the sheep placenta and fetus in utero. Distribution to cotyledons and the intercotyledonary chorion.
نویسندگان
چکیده
A method of estimating the magnitude and distribution of umbilical blood flow by means of radioactive microspheres in sheep fetuses in utero is described. Simultaneous measurements of total umbilical flow by this method and the steady-state diffusion technique showed agreement within ± 11%. In 11 fetuses of 90 to 150 days gestational age, the distribution of umbilical flow to the intercotyledonary chorion was 6.2 ± 0.8% of the total. This information has been used to estimate the effect of venous admixture of cotyledonary and noncotyledonary blood on the umbilical vein-uterine vein concentration difference of inert molecules with flow-limited transplacental clearance. ADDITIONAL
منابع مشابه
Measurement of Umbilical Arterial Blood Flow to the Sheep Placenta and Fetus in Utero
A method of estimating the magnitude and distribution of umbilical blood flow by means of radioactive microspheres in sheep fetuses in utero is described. Simultaneous measurements of total umbilical flow by this method and the steady-state diffusion technique showed agreement within ± 11%. In 11 fetuses of 90 to 150 days gestational age, the distribution of umbilical flow to the intercotyledon...
متن کاملRelationships between pressure and flow in the umbilical and uterine circulations of the sheep.
We studied the relationship of fetal and maternal vascular pressures to umbilical and uterine blood flow in the unanesthetized ewe and in the sheep fetus in utero by placing electromagnetic flow transducers around both the common umbilical and uterine arteries. Reductions in umbilical arterial pressure or elevations in umbilical venous pressure decreased umbilical blood flow without affecting e...
متن کاملThe effects of hypoxaemia in fetal sheep.
Fetal hypoxaemia may result from altered maternal PaO2 or a reduction in maternal placental or umbilical blood flow. It is also possible that reduction of gas exchange across the placenta could limit the oxygen supply to the fetus. In this review we will be concerned with the effects of hypoxaemia in fetal sheep during the latter half of pregnancy. At present it is not easy to reduce maternal p...
متن کاملHemodynamic responses of the sheep fetus to vasopressin infusion.
The effects of intravenous infusion of vasopressin on the circulation of the fetus were studied in lambs in utero with chronically maintained intravascular catheters. Vasopressin infused in doses of 0.91-2.26 mU/min per kg fetal weight resulted in plasma levels of arginine vasopressin of 6.836.4 /iU/ml; these levels are similar to those achieved during fetal hypoxia. Petal mean arterial blood p...
متن کاملI-46: Obstetrical Doppler
Accurate assessment of gestational age, fetal growth, and the detection of fetal and placental abnormalities are major benefits of sonography. Color Doppler can be used to assist in the identification of vascular architecture, detection of vascular pathology and visualization of blood flow changes associated with physiologic processes and disease states. The clinical applications of obstetrical...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Circulation research
دوره 23 5 شماره
صفحات -
تاریخ انتشار 1968