Umbilical Blood Flow and Glucose Uptake in Lamb Fetus Following Single Umbilical Artery Ligation

Neonatology ◽  
1975 ◽  
Vol 26 (3-4) ◽  
pp. 291-299 ◽  
Author(s):  
William Oh ◽  
Keiichiro Omori ◽  
Calvin J. Hobel ◽  
Allen Erenberg ◽  
George C. Emmanouilides
Keyword(s):  
Blood Flow ◽  
Glucose Uptake ◽  
Umbilical Artery ◽  
Single Umbilical Artery ◽  
Artery Ligation ◽  
Umbilical Blood ◽  
Umbilical Blood Flow

Hemodynamic model for analysis of Doppler ultrasound indexes of umbilical blood flow

1999 ◽  
Vol 276 (6) ◽  
pp. H2204-H2214 ◽  
Author(s):  
Ayala Kleiner-Assaf ◽  
Ariel J. Jaffa ◽  
David Elad
Keyword(s):  
Blood Flow ◽  
Flow Rate ◽  
Umbilical Artery ◽  
Blood Flow Rate ◽  
Velocity Profiles ◽  
Fetal Blood ◽  
System Parameters ◽  
Umbilical Blood ◽  
Hemodynamic Model ◽  
Umbilical Blood Flow

A hemodynamic model for pulsatile fluid flow in a pressurized thin-walled elastic tube was applied for the computation of volumetric blood flow and velocity profiles for a given set of system parameters at any selected location along the umbilical artery. The velocity profiles over one heart cycle provide the fetal blood flow velocity waveforms (FVW) from which the usual Doppler indexes (DI) can be derived. The model was used for a comprehensive investigation of the correlation between DI and system parameters that reflect the anatomy and physiology of umbilical blood flow. The simulations showed that the radial location of the Doppler measurement is insignificant for the calculated DI, whereas the axial site is important. The analysis showed that decreasing the diameter or increasing the length of the umbilical artery reduces fetal mean blood flow rate and increases the DI. Increasing blood viscosity tends to induce similar patterns, whereas decreasing arterial compliance or increasing blood density decreases the DI with little effect on blood flow rate. Fetal heart rate has a minor effect on both DI and fetal blood flow rate. This study provides insight into the dependence of DI on the anatomic and physiological characteristics of umbilical blood flow.

Placental transfer as a function of uterine blood flow

1982 ◽  
Vol 242 (3) ◽  
pp. H429-H436 ◽  
Author(s):  
R. B. Wilkening ◽  
S. Anderson ◽  
L. Martensson ◽  
G. Meschia
Keyword(s):  
Blood Flow ◽  
Placental Transfer ◽  
Appreciable Effect ◽  
Uterine Blood Flow ◽  
Placental Perfusion ◽  
Umbilical Blood ◽  
Norepinephrine Infusion ◽  
Umbilical Blood Flow ◽  
Clearance Level ◽  
Different Levels

The effect of variations of uterine blood flow (F) on placental transfer was examined in six chronic sheep preparations by measuring the placental clearances of ethanol (CE) and antipyrine (CA) at different levels of F. Norepinephrine infusion, hemorrhage, and occlusion of the terminal aorta were used to reduce F below normal. The reduction of F had no appreciable effect on umbilical blood flow (f). In each ewe, CE significantly correlated with F. The CE vs. F relationship at constant f was curvilinear with convexity toward the clearance axis. Regression analysis showed that the equation 1/CE = 1/.911 F + 1/.831 f could account for most of the CE variance (r2 = 0.97). Implicit in this relation is the concept that, given a certain level of placental perfusion, an F/f ratio congruent to 1 is optimal for the exchange of highly diffusible inert molecules between mother and fetus [CE/(F + f) was maximum at F/f = 0.955]. CA was not significantly different from CE at low clearance level but became smaller than CE at clearance values greater than 300 ml/min. This suggests that a high rates of perfusion placental permeability was a factor in limiting CA.

scholarly journals CSH RNA Interference Reduces Global Nutrient Uptake and Umbilical Blood Flow Resulting in Intrauterine Growth Restriction

2021 ◽  
Vol 22 (15) ◽  
pp. 8150
Author(s):  
Amelia R. Tanner ◽  
Cameron S. Lynch ◽  
Victoria C. Kennedy ◽  
Asghar Ali ◽  
Quinton A. Winger ◽  
...  
Keyword(s):  
Blood Flow ◽  
Rna Interference ◽  
Nutrient Uptake ◽  
Intrauterine Growth Restriction ◽  
Growth Restriction ◽  
Intrauterine Growth ◽  
Umbilical Blood ◽  
Uterine Growth ◽  
Umbilical Blood Flow ◽  
Placental Hormone

Deficiency of the placental hormone chorionic somatomammotropin (CSH) can lead to the development of intrauterine growth restriction (IUGR). To gain insight into the physiological consequences of CSH RNA interference (RNAi), the trophectoderm of hatched blastocysts (nine days of gestational age; dGA) was infected with a lentivirus expressing either a scrambled control or CSH-specific shRNA, prior to transfer into synchronized recipient sheep. At 90 dGA, umbilical hemodynamics and fetal measurements were assessed by Doppler ultrasonography. At 120 dGA, pregnancies were fitted with vascular catheters to undergo steady-state metabolic studies with the 3H2O transplacental diffusion technique at 130 dGA. Nutrient uptake rates were determined and tissues were subsequently harvested at necropsy. CSH RNAi reduced (p ≤ 0.05) both fetal and uterine weights as well as umbilical blood flow (mL/min). This ultimately resulted in reduced (p ≤ 0.01) umbilical IGF1 concentrations, as well as reduced umbilical nutrient uptakes (p ≤ 0.05) in CSH RNAi pregnancies. CSH RNAi also reduced (p ≤ 0.05) uterine nutrient uptakes as well as uteroplacental glucose utilization. These data suggest that CSH is necessary to facilitate adequate blood flow for the uptake of oxygen, oxidative substrates, and hormones essential to support fetal and uterine growth.

The effect of steroids on the fetal brain and umbilical blood flow and biophysical profile

2003 ◽  
Vol 189 (6) ◽  
pp. S218
Author(s):  
Zeev Weiner ◽  
Rula Hamisa ◽  
Allan Fisher ◽  
Allan Bombard ◽  
Eliezer Shalev
Keyword(s):  
Blood Flow ◽  
Fetal Brain ◽  
Umbilical Blood ◽  
Biophysical Profile ◽  
Umbilical Blood Flow

Effects of Pharmacologic Agents on Umbilical Blood Flow in Fetal Lambs in utero

Neonatology ◽  
1978 ◽  
Vol 33 (5-6) ◽  
pp. 225-235 ◽  
Author(s):  
William Berman jr. ◽  
Robert C. Goodlin ◽  
Michael A. Heymann ◽  
Abraham M. Rudolph
Keyword(s):  
Blood Flow ◽  
In Utero ◽  
Umbilical Blood ◽  
Umbilical Blood Flow ◽  
Pharmacologic Agents

scholarly journals A comparative study of three indices of umbilical blood flow in relation to prediction of growth retardation

1987 ◽  
Vol 15 (1) ◽  
pp. 3-12 ◽  
Author(s):  
Léon G. M. Mulders ◽  
Pieter F. F. Wijn ◽  
Henk W. Jongsma ◽  
Peter R. Hein
Keyword(s):  
Blood Flow ◽  
Comparative Study ◽  
Growth Retardation ◽  
Umbilical Blood ◽  
Umbilical Blood Flow

EFFECTS OF SINGLE UMBILICAL ARTERY LIGATION IN THE LAMB FETUS

1969 ◽  
Vol 24 (8) ◽  
pp. 1068-1070 ◽  
Author(s):  
GEORGE C. EMMANOUILIDES ◽  
DUANE E. TOWNSEND ◽  
ROBERT A. BAUER
Keyword(s):  
Umbilical Artery ◽  
Single Umbilical Artery ◽  
Artery Ligation

EFFECTS OF EPIDURAL BLOCK WITH L1DOCAINE AND LIDOCAINE-EPINEPHRINE ON UMBILICAL BLOOD FLOW VELOCITY WAVEFORMS

1986 ◽  
Vol 65 (Supplement 3A) ◽  
pp. A378
Author(s):  
G. F. Marx ◽  
M. Schuss ◽  
A. Anyaegbunam ◽  
A. Fleischer
Keyword(s):  
Blood Flow ◽  
Flow Velocity ◽  
Blood Flow Velocity ◽  
Epidural Block ◽  
Umbilical Blood ◽  
Umbilical Blood Flow
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