INTERRELATIONSHIPS OF MATERNAL AND FETAL CIRCULATIONS

PEDIATRICS ◽  
1961 ◽  
Vol 27 (4) ◽  
pp. 627-635
Author(s):  
Forrest H. Adams ◽  
Nicholas Assali ◽  
Marjorie Cushman ◽  
Allan Westersten

Epinephrine and norepinephrine injected intravenously into pregnant ewes produced a prompt increase in maternal arterial pressure but a significant and sustained decrease in uterine arterial blood flow. Angiotensin injected intravenously into pregnant ewes produced a prompt increase in maternal arterial pressure (similar to epinephrine and norepinephrine) and an increase in uterine arterial blood flow. In the doses used, epinephrine, norepinephrine and angiotensin injected intravenously into pregnant ewes produced no significant observable effects on the arterial pressure and blood flow in the umbilical cord on heart rate in the fetus. Epinephrine and norepinephrine injected in the umbilical vein of lambs in utero produced a prompt and significant rise in umbilical arterial pressure and umbilical arterial flow only when large doses (five times effective adult doses/kg body weight) were used. Effective adult doses (kg body weight) injected into lambs in utero produced no significant change in arterial pressure or blood flow in the fetus. Angiotensin injected intravenously into lambs in utero produced no significant change in arterial pressure or blood flow in the umbilical cord. Vasoactive drugs injected into the mother on into the fetus did not appear to cross the placenta in either direction in physiologically effective amounts.

2018 ◽  
Vol 1 ◽  
pp. 10
Author(s):  
Matin Goldooz ◽  
Mike Draper ◽  
Jessica Comstock ◽  
Anne Kennedy

Umbilical cord hemangiomas are rare tumors of the umbilical cord. Doppler ultrasound has been shown to be useful in the diagnosis of cord hemangioma and evaluation of arterial blood flow through the mass. In this study, we present a 28-year-old pregnant woman with an umbilical cord mass with solid and cystic components. She was followed with weekly umbilical artery (UA) Doppler ultrasound, but the fact that the umbilical vein (UV) ran in the wall of the mass was not noted prospectively. At the time of placental delivery, the cystic component of the mass ruptured tearing the UV causing significant bleeding. The case illustrates the importance of using Doppler ultrasound to both look for UA compromise and to map the UV location through the entirety of the cord.


2009 ◽  
Vol 17 (3) ◽  
pp. 258-268 ◽  
Author(s):  
Aaron D. Kaplan ◽  
Ariel J. Jaffa ◽  
Ilan E. Timor ◽  
David Elad

2002 ◽  
Vol 93 (6) ◽  
pp. 1966-1972 ◽  
Author(s):  
Maria T. E. Hopman ◽  
Jan T. Groothuis ◽  
Marcel Flendrie ◽  
Karin H. L. Gerrits ◽  
Sibrand Houtman

The purpose of the present study was to determine the effect of a spinal cord injury (SCI) on resting vascular resistance in paralyzed legs in humans. To accomplish this goal, we measured blood pressure and resting flow above and below the lesion (by using venous occlusion plethysmography) in 11 patients with SCI and in 10 healthy controls (C). Relative vascular resistance was calculated as mean arterial pressure in millimeters of mercury divided by the arterial blood flow in milliliters per minute per 100 milliliters of tissue. Arterial blood flow in the sympathetically deprived and paralyzed legs of SCI was significantly lower than leg blood flow in C. Because mean arterial pressure showed no differences between both groups, leg vascular resistance in SCI was significantly higher than in C. Within the SCI group, arterial blood flow was significantly higher and vascular resistance significantly lower in the arms than in the legs. To distinguish between the effect of loss of central neural control vs. deconditioning, a group of nine SCI patients was trained for 6 wk and showed a 30% increase in leg blood flow with unchanged blood pressure levels, indicating a marked reduction in vascular resistance. In conclusion, vascular resistance is increased in the paralyzed legs of individuals with SCI and is reversible by training.


1993 ◽  
Vol 71 (6) ◽  
pp. 1238-1241 ◽  
Author(s):  
Peter S. Davie ◽  
Craig E. Franklin

Coronary arterial blood flow and pressure, intraventricular blood pressure, and ventral aortic blood velocity were measured in two anaesthetized school sharks (Galeorhinus australis) in order to examine the phasic relationships between these flows and pressures. Maximum instantaneous flow recorded in the ventral coronary artery was 0.37 mL∙min−1∙kg−1 body mass (estimated 0.63 mL∙min−1∙g−1 ventricular mass). The average mean coronary blood flow was estimated as 0.28 mL∙min−1∙g−1 ventricular mass during periods of high coronary blood flow. On average, 86% of coronary flow occurred during diastole. Coronary arterial flow began during the last quarter of ventricular systole. Coronary blood flow peaked when intraventricular pressure fell to just below zero immediately after ventricular systole. Coronary blood flow fell slightly as diastole continued and reflected the small fall in coronary arterial pressure. Coronary flow reversed briefly during isovolumic ventricular contraction. Increases in the proportion of the cardiac cycle occupied by ventricular diastole, which occur during hypoxic bradycardia, have the potential to more than double coronary blood flow provided coronary arterial pressure is maintained.


1969 ◽  
Vol 24 (7) ◽  
pp. 602-607
Author(s):  
EDGAR L. MAKOWSKI ◽  
GIACOMO MESCHIA ◽  
WILLIAM DROEGEMUELLER ◽  
FREDERICK C. BATTAGLIA

1958 ◽  
Vol 193 (2) ◽  
pp. 360-364 ◽  
Author(s):  
Allan V. N. Goodyer ◽  
Louis R. Mattie ◽  
Allen Chetrick

In anesthetized dogs, bleeding (1.5–3% of the body weight) was allowed while renal arterial pressure was maintained at constant levels by graded changes of mechanical aortic obstruction. The renal hematocrit decreased, (as measured with I131 albumin and acid hematin, and as compared to the blood hematocrit), primarily as a result of an increased renal plasma volume. These changes are correlated with previously identified alterations of sodium excretion, all independent of renal innervation or arterial blood pressure. It is proposed that hemorrhage may involve an intrarenal redistribution of blood flow favoring diversion of plasma to cell-poor capillaries or to lymphatic spaces.


1988 ◽  
Vol 66 (12) ◽  
pp. 1493-1498 ◽  
Author(s):  
José M. Romeo ◽  
Antonio López-Farré ◽  
Vicente Martín-Paredero ◽  
José M. López-Novoa

The effect of surgical end-to-side portacaval anastomosis (PCSA) on systemic and splanchnic circulation has been studied in cirrhotic rats with portal hypertension (CCl4–Phenobarbital method) and in control animals. Hemodynamics have been measured using the microsphere technique, with a reference sample for the systemic hemodynamic measurements, and intrasplenic injection for portal systemic shunting rate measurements. Compared with controls, sham-operated (SO) cirrhotic rats showed a hyperdynamic circulation with increased cardiac output (CO) and decreased mean arterial pressure and peripheral resistances. PCSA in control rats induced only a small change in systemic hemodynamics, with parallel decreases in arterial pressure and peripheral resistances, and a small, nonsignificant increase in CO. In cirrhotic rats, PCSA induced a decrease of CO to values similar to those of control rats, with an increase in total peripheral resistances. PCSA induced an increase in hepatic arterial blood flow in control and in cirrhotic rats, portal pressure becoming in this latter group not different from that of control rats. Blood flow to splanchnic organs was higher in SO cirrhotic than in SO control animals. Thus portal venous inflow was also increased in SO cirrhotic rats. PCSA induced an increase in portal venous inflow in control rats, which was only significant in cirrhotic rats when expressed as a percentage of CO. In SO control animals, a significant correlation was observed between total peripheral resistances and splanchnic arteriolar resistances and between CO and splanchnic blood flow. These correlations were not observed in cirrhotic rats. These results do not support the hypothesis that hyperdynamic circulation shown by cirrhotic rats is based on increases in splanchnic blood flow and (or) massive portal systemic shunting.


1968 ◽  
Vol 23 (5) ◽  
pp. 623-631 ◽  
Author(s):  
EDGAR L. MAKOWSKI ◽  
GIACOMO MESCHIA ◽  
WILLIAM DROEGEMUELLER ◽  
FREDERICK C. BATTAGLIA

1965 ◽  
Vol 209 (1) ◽  
pp. 37-50 ◽  
Author(s):  
Ricardo Ferretti ◽  
Neil S. Cherniack ◽  
Guy Longobardo ◽  
O. Robert Levine ◽  
Eugene Morkin ◽  
...  

Rhythmic oscillations in systemic arterial blood pressure (Mayer waves) were produced in the dog by metabolic acidosis; hypoxia generally augmented the amplitude of the Mayer waves. When the Mayer waves exceeded 20 mm Hg in amplitude, they were associated with rhythmic fluctuations in pulmonary arterial pressure. The pulmonary arterial waves resembled the Mayer waves with respect to frequency and independence of the breathing pattern but were generally smaller in amplitude Measurements of instantaneous pulmonary arterial blood flow indicate that the rhythmic fluctuations in pulmonary arterial pressure represent the passive effects of fluctuations in pulmonary blood flow rather than fluctuations in pulmonary vasomotor activity. In turn, the swings in pulmonary arterial blood flow appear to originate in rhythmic variations in systemic vasomotor activity.


1975 ◽  
Vol 228 (2) ◽  
pp. 386-391 ◽  
Author(s):  
LA Hohnke

Arterial blood pressure (ABP) responses to graded hemorrhage and passive head-up tilt were studied in restrained, anesthetized, and unanesthetized iguanas. The ABP fell slowly in response to hemorrhage up to a critical deficit of 35 plus or minus 19% of the estimated blood volume; the rate of ABP fall then increased nearly 40-fold to continued hemorrhage. Increased heart rate and decreased femoral arterial blood flow accompanied progressive hemorrhage. Propranolol (2-3 mug/kg) did not appreciably alter arterial pressure-hemorrhage curves but hemorrhage-induced increases in heart rate were diminished nearly 50%. Atropine had little effect on either the blood pressure or heart rate changes induced by hemorrhage. During passive tilts of 0-90 degrees carotid arterial pressure fell 33% before returning to control levels (2 min). Heart rate increased and femoral arterial blood flow and central venous pressure fell in response to head-up tilts. It is concluded that hemorrhage and passive head-up tilting can induce reflex cardiovascular changes that assist ABP regulation in iguanas.


Sign in / Sign up

Export Citation Format

Share Document