scholarly journals Fetal aortic isthmus blood flow and the fraction of cardiac output distributed to the upper body and brain at 11- 20 weeks of gestation

2009 ◽  
Vol 33 (5) ◽  
pp. 538-544 ◽  
Author(s):  
T. Vimpeli ◽  
H. Huhtala ◽  
T. Wilsgaard ◽  
G. Acharya
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
Upper Body ◽  
Aortic Isthmus

Effects of cord compression on fetal blood flow distribution and O2 delivery

1987 ◽  
Vol 252 (1) ◽  
pp. H100-H109 ◽  
Author(s):  
J. Itskovitz ◽  
E. F. LaGamma ◽  
A. M. Rudolph
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
Cord Compression ◽  
Upper Body ◽  
Ductus Venosus ◽  
Foramen Ovale ◽  
Arterial Blood ◽  
O2 Delivery ◽  
The Brain ◽  
Distribution Of Cardiac Output

We used the radionuclide microsphere technique in nine fetal lambs to examine the effect of partial cord compression on distribution of cardiac output and O2 delivery to fetal organs and venous flow patterns. With a 50% reduction in umbilical blood flow the fraction of fetal cardiac output distributed to the brain, heart, carcass, kidneys, and gastrointestinal tract increased. Pulmonary blood flow fell. O2 delivery to the brain and myocardium was maintained but was reduced to peripheral, renal, and gastrointestinal circulations. Hepatic blood flow decreased and O2 delivery fell by 75%. The proportion of umbilical venous blood passing through the ductus venosus increased from 43.9 to 71.8%. The preferential distribution of ductus venosus blood flow through the foramen ovale was enhanced (29.4 vs. 47.2%) and the proportion of O2 delivery to upper body organs derived from the ductus venosus increased (33.2 vs. 49.4%). Abdominal inferior vena caval blood flow increased, and it was also preferentially distributed through the foramen ovale (21.9 vs. 44.2%) and constituted the major fraction of the arterial blood supply to the upper body organs (16.5 vs. 36.4%). Thus cord compression modified the distribution of cardiac output and the patterns of venous returns in the fetus. This pattern of circulatory response differs from that observed with other causes of reduced O2 delivery.

Diastolic pressure and peripheral resistance during stellate ganglion stimulation

1963 ◽  
Vol 204 (1) ◽  
pp. 71-72 ◽  
Author(s):  
Edward D. Freis ◽  
Jay N. Cohn ◽  
Thomas E. Liptak ◽  
Aristide G. B. Kovach
Keyword(s):  
Heart Rate ◽  
Blood Flow ◽  
Cardiac Output ◽  
Total Peripheral Resistance ◽  
Diastolic Pressure ◽  
Stellate Ganglion ◽  
Peripheral Resistance ◽  
Resistance Vessels ◽  
Left Stellate Ganglion ◽  
Increased Blood Flow

The mechanism of the diastolic pressure elevation occurring during left stellate ganglion stimulation was investigated. The cardiac output rose considerably, the heart rate remained essentially unchanged, and the total peripheral resistance fell moderately. The diastolic rise appeared to be due to increased blood flow rather than to any active changes in resistance vessels.

scholarly journals The use of pulse pressure variation for predicting impairment of microcirculatory blood flow

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Christoph R. Behem ◽  
Michael F. Graessler ◽  
Till Friedheim ◽  
Rahel Kluttig ◽  
Hans O. Pinnschmidt ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
Reperfusion Injury ◽  
Pulse Pressure ◽  
Pulse Pressure Variation ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Pressure Variation ◽  
Volume Loading ◽  
Microcirculatory Blood Flow

AbstractDynamic parameters of preload have been widely recommended to guide fluid therapy based on the principle of fluid responsiveness and with regard to cardiac output. An equally important aspect is however to also avoid volume-overload. This accounts particularly when capillary leakage is present and volume-overload will promote impairment of microcirculatory blood flow. The aim of this study was to evaluate, whether an impairment of intestinal microcirculation caused by volume-load potentially can be predicted using pulse pressure variation in an experimental model of ischemia/reperfusion injury. The study was designed as a prospective explorative large animal pilot study. The study was performed in 8 anesthetized domestic pigs (German landrace). Ischemia/reperfusion was induced during aortic surgery. 6 h after ischemia/reperfusion-injury measurements were performed during 4 consecutive volume-loading-steps, each consisting of 6 ml kg−1 bodyweight−1. Mean microcirculatory blood flow (mean Flux) of the ileum was measured using direct laser-speckle-contrast-imaging. Receiver operating characteristic analysis was performed to determine the ability of pulse pressure variation to predict a decrease in microcirculation. A reduction of ≥ 10% mean Flux was considered a relevant decrease. After ischemia–reperfusion, volume-loading-steps led to a significant increase of cardiac output as well as mean arterial pressure, while pulse pressure variation and mean Flux were significantly reduced (Pairwise comparison ischemia/reperfusion-injury vs. volume loading step no. 4): cardiac output (l min−1) 1.68 (1.02–2.35) versus 2.84 (2.15–3.53), p = 0.002, mean arterial pressure (mmHg) 29.89 (21.65–38.12) versus 52.34 (43.55–61.14), p < 0.001, pulse pressure variation (%) 24.84 (17.45–32.22) versus 9.59 (1.68–17.49), p = 0.004, mean Flux (p.u.) 414.95 (295.18–534.72) versus 327.21 (206.95–447.48), p = 0.006. Receiver operating characteristic analysis revealed an area under the curve of 0.88 (CI 95% 0.73–1.00; p value < 0.001) for pulse pressure variation for predicting a decrease of microcirculatory blood flow. The results of our study show that pulse pressure variation does have the potential to predict decreases of intestinal microcirculatory blood flow due to volume-load after ischemia/reperfusion-injury. This should encourage further translational research and might help to prevent microcirculatory impairment due to excessive fluid resuscitation and to guide fluid therapy in the future.

Increase in hepatic blood flow and cardiac output during dopamine infusion in man

1981 ◽  
Vol 9 (1) ◽  
pp. 14-16 ◽  
Author(s):  
P. MAESTRACCI ◽  
D. GRIMAUD ◽  
N. LIVRELLI ◽  
F. PHILIP ◽  
C. DOLISI
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
Hepatic Blood Flow ◽  
Dopamine Infusion

Control of Blood Pressure and the Distribution of Blood Flow

1991 ◽  
Vol 7 (S1) ◽  
pp. 79-84 ◽  
Author(s):  
Hans T. Versmold
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Cardiac Output ◽  
Peripheral Resistance ◽  
Systemic Blood Pressure ◽  
Adrenergic Innervation ◽  
Systemic Blood ◽  
Low Cardiac Output ◽  
Neurohumoral Control ◽  
The Brain

Systemic blood pressure (BP) is the product of cardiac output and total peripheral resistance. Cardiac output is controlled by the heart rate, myocardial contractility, preload, and afterload. Vascular resistance (vascular hindrance × viscosity) is under local autoregulation and general neurohumoral control through sympathetic adrenergic innervation and circulating catecholamines. Sympathetic innovation predominates in organs receivingflowin excess of their metabolic demands (skin, splanchnic organs, kidney), while innervation is poor and autoregulation predominates in the brain and heart. The distribution of blood flow depends on the relative resistances of the organ circulations. During stress (hypoxia, low cardiac output), a raise in adrenergic tone and in circulating catecholamines leads to preferential vasoconstriction in highly innervated organs, so that blood flow is directed to the brain and heart. Catecholamines also control the levels of the vasoconstrictors renin, angiotensin II, and vasopressin. These general principles also apply to the neonate.

scholarly journals Reference values for an index of fetal aortic isthmus blood flow during the second half of pregnancy

2003 ◽  
Vol 21 (5) ◽  
pp. 441-444 ◽  
Author(s):  
J. Ruskamp ◽  
J.-C. Fouron ◽  
J. Gosselin ◽  
M.-J. Raboisson ◽  
C. Infante-Rivard ◽  
...  
Keyword(s):  
Blood Flow ◽  
Reference Values ◽  
Aortic Isthmus

Improved cardiac output and peripheral blood flow after correcting neonatal hyperviscosity

1985 ◽  
Vol 110 (3) ◽  
pp. 707
Author(s):  
Sydney Swetnam ◽  
Dale Alverson ◽  
Steven M. Yabek ◽  
Pam Angelus ◽  
Connie Bakstrom ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
Peripheral Blood ◽  
Peripheral Blood Flow

Cardiac Output and Liver Blood Flow in Humans

1992 ◽  
Vol 36 (6) ◽  
pp. 341
Author(s):  
P. ALTMAYER ◽  
U. GRUNDMANN ◽  
M. ZIEHMER ◽  
R. LARSEN ◽  
H. P. B??CH
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
Liver Blood Flow

Human respiratory muscle blood flow measured by near-infrared spectroscopy and indocyanine green

2008 ◽  
Vol 104 (4) ◽  
pp. 1202-1210 ◽  
Author(s):  
Jordan A. Guenette ◽  
Ioannis Vogiatzis ◽  
Spyros Zakynthinos ◽  
Dimitrios Athanasopoulos ◽  
Maria Koskolou ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
Infrared Spectroscopy ◽  
Respiratory Muscle ◽  
Near Infrared ◽  
Vastus Lateralis ◽  
Muscle Blood Flow ◽  
Work Of Breathing ◽  
Dilution Method ◽  
Transdiaphragmatic Pressure

Measurement of respiratory muscle blood flow (RMBF) in humans has important implications for understanding patterns of blood flow distribution during exercise in healthy individuals and those with chronic disease. Previous studies examining RMBF in humans have required invasive methods on anesthetized subjects. To assess RMBF in awake subjects, we applied an indicator-dilution method using near-infrared spectroscopy (NIRS) and the light-absorbing tracer indocyanine green dye (ICG). NIRS optodes were placed on the left seventh intercostal space at the apposition of the costal diaphragm and on an inactive control muscle (vastus lateralis). The primary respiratory muscles within view of the NIRS optodes include the internal and external intercostals. Intravenous bolus injection of ICG allowed for cardiac output (by the conventional dye-dilution method with arterial sampling), RMBF, and vastus lateralis blood flow to be quantified simultaneously. Esophageal and gastric pressures were also measured to calculate the work of breathing and transdiaphragmatic pressure. Measurements were obtained in five conscious humans during both resting breathing and three separate 5-min bouts of constant isocapnic hyperpnea at 27.1 ± 3.2, 56.0 ± 6.1, and 75.9 ± 5.7% of maximum minute ventilation as determined on a previous maximal exercise test. RMBF progressively increased (9.9 ± 0.6, 14.8 ± 2.7, 29.9 ± 5.8, and 50.1 ± 12.5 ml·100 ml−1·min−1, respectively) with increasing levels of ventilation while blood flow to the inactive control muscle remained constant (10.4 ± 1.4, 8.7 ± 0.7, 12.9 ± 1.7, and 12.2 ± 1.8 ml·100 ml−1·min−1, respectively). As ventilation rose, RMBF was closely and significantly correlated with 1) cardiac output ( r = 0.994, P = 0.006), 2) the work of breathing ( r = 0.995, P = 0.005), and 3) transdiaphragmatic pressure ( r = 0.998, P = 0.002). These data suggest that the NIRS-ICG technique provides a feasible and sensitive index of RMBF at different levels of ventilation in humans.

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