scholarly journals Mammary Blood Flow and Venous Drainage in Cows

1974 ◽  
Vol 15 (2) ◽  
pp. 179-187
Author(s):  
Per Kjœrsgaard
Keyword(s):  
Blood Flow ◽  
Venous Drainage

scholarly journals Blood Flow in Portal Systems with Special Reference to the Rat Pituitary Gland

1992 ◽  
Vol 12 (1) ◽  
pp. 128-138 ◽  
Author(s):  
P. D. Lees ◽  
D. T. Lynch ◽  
H. K. Richards ◽  
A. H. J. Lovick ◽  
S. Perry ◽  
...  
Keyword(s):  
Blood Flow ◽  
Flow Rate ◽  
Median Eminence ◽  
Venous Drainage ◽  
Mean Value ◽  
Portal System ◽  
Posterior Pituitary ◽  
Flow Rates ◽  
Fischer 344 ◽  
Rat Pituitary

Regional pituitary blood flow has been studied in adult female Fischer 344 rats by [14C]iodoantipyrine autoradiography. A general mathematical solution has been derived to allow the calculation of blood flow in the second compartment of a portal system and the proportion of blood “shunted” through the first compartment without exposure to tissue uptake from a knowledge of (a) the volume ratios of the two compartments, (b) the tissue tracer uptakes of the two compartments, and (c) the arterial tracer concentration with respect to time of a freely diffusible tracer. Significant diffusion limitation and/or arteriovenous shunting has been demonstrated in the neurohypophysis, suggesting that the majority of incoming blood is “shunted” unchanged to the adenohypophysis. The mean value of the shunt is 89% (range of 84–93%) for the median eminence and lies between 72% (range of 52–82%) and 73% (range of 59–81%) for the posterior pituitary. Neurohypophysial flow rates of 1.20 (range of 0.99–1.55) ml g−1 min−1 for the median eminence and 1.68 (range of 0.83–3.53) ml g−1 min−1 for the posterior pituitary were measured. These values represent “tissue-available” (nonshunted) flow; estimated mean total (shunted plus nonshunted) neurohypophysial flow rates were 11.7 (range of 9.5–17.5) ml g−1 min−1 for the median eminence and 6.1 (range of 3.1–8.9) ml g−1 min−1 (minimum) for the posterior pituitary. Adenohypophysial blood flow is heterogeneous. In the long portal territory, the flow rate was 1.18 (range of 0.95–1.75) ml g−1 min−1 but short portal territory flow calculation is complicated by an unquantifiable nonportal venous drainage; using the natural limits of zero and 100% gives a minimum adenohypophysial flow rate of 1.42 (range of 0.76–2.07) ml g−1 min−1 and a maximum value of 1.97 (range of 1.03–2.82) ml g−1 min−1.

scholarly journals Arterio–venous differences to study macronutrient metabolism: introduction and overview

1999 ◽  
Vol 58 (4) ◽  
pp. 871-875 ◽  
Author(s):  
I. A. Macdonald
Keyword(s):  
Blood Flow ◽  
Venous Drainage ◽  
Volume Of Distribution ◽  
Tissue Metabolism ◽  
Unidirectional Flux ◽  
Arterial Blood ◽  
Transit Times ◽  
Arterial Concentration ◽  
Flow Through ◽  
Different Tissues

The arterio-venous difference technique is now well established in the study of organ and tissue metabolism. This technique requires samples to be obtained of the arterial blood supplying and the venous drainage from a tissue, together with a measurement of the blood flow through the tissue. The technique is most appropriate when the arterial concentration and tissue metabolism of a substance are constant, and when the blood flow is stable. If these criteria are not satisfied, care is needed in the interpretation of the results obtained. It should be recognized that the arterio-venous difference technique only measures the net exchange of a substance with the tissue, and that tracers are needed if unidirectional flux needs to be estimated. The other factors which must be borne in mind when intending to use this technique are the transit times of blood and the substance of interest through a tissue, the volume of distribution of the substance in the tissue, and the possibility that the venous samples obtained are derived from a mixture of different tissues.

Color Doppler Ultrasound Evaluation of Internal Jugular Vein Before Radical Neck Dissection

2019 ◽  
Vol 9 (2) ◽  
pp. 371-375
Author(s):  
Zhiyong Chen ◽  
Binshan Zha ◽  
Yan Li ◽  
Yongchao Chen
Keyword(s):  
Blood Flow ◽  
Neck Dissection ◽  
Color Doppler ◽  
Radical Neck Dissection ◽  
Venous Drainage ◽  
Color Doppler Ultrasound ◽  
Sitting Position ◽  
Section Area ◽  
Cerebral Venous Drainage ◽  
The Right

Objective: There is a great controversy about whether the internal jugular vein (IJV) should be retained during radical neck dissection. In this study, the right and left IJV under different body position were observed by color Doppler ultrasound, in order to provide a experimental basis for the preservation of IJV in neck dissections. Methods: A total of 40 patients with thyroid cancer undergoing radical neck dissection were examined in this study. The hemodynamic data such as section area, velocity, and volume of blood flow were measured by Doppler in supine and sitting position under quiet breath. Results: In supine position, the cross sectional area, the velocity and the blood flow volume in the right side were 58%, 23% and 91% more than left side respectively. The right side advantage, symmetrical, and left side advantage of IJV was in 65%, 25%, and 10% of patients. The blood flow of bilateral IJV was 74% of total cerebral outflow. The IJV predominate, balanced type, and no-IJV predominate cerebral venous drainage was in 73%, 23% and 5% of patients. In sitting position, the section area, the velocity and the blood flow volume in the right side were 29%, 35% and 56% more than left side respectively. The right side advantage, symmetrical, and left side advantage of IJV was in 45%, 45%, and 10% of patients. The blood flow of bilateral IJV was 23% of total cerebral outflow. The balanced type and no-IJV predominate cerebral venous drainage was in 23% and 78% of patients. Conclusions: There are side advantage of IJV. With quiet breathing, IJV is not the main pathway of cerebral venous drainage in sitting position. The preoperative ultrasound is useful to design the individualized surgical approach for the radical neck dissections.

Distribution of blood flow and neutrophil kinetics in bronchial vasculature of sheep

1997 ◽  
Vol 82 (5) ◽  
pp. 1466-1471 ◽  
Author(s):  
Elisabeth M. Baile ◽  
Peter D. Paré ◽  
David Ernest ◽  
Peter M. Dodek
Keyword(s):  
Blood Flow ◽  
Bronchial Artery ◽  
Airflow Obstruction ◽  
Venous Drainage ◽  
Inflammatory Cells ◽  
Pulmonary Vasculature ◽  
Relative Distribution ◽  
Edema Formation ◽  
Airway Narrowing ◽  
Neutrophil Kinetics

Baile, Elisabeth M., Peter D. Paré, David Ernest, and Peter M. Dodek. Distribution of blood flow and neutrophil kinetics in bronchial vasculature of sheep. J. Appl. Physiol. 82(5): 1466–1471, 1997.—The bronchial circulation, as opposed to the pulmonary circulation, is the likely source of the edema and inflammatory cells that contribute to airflow obstruction and airway narrowing associated with asthma and pulmonary edema. The purpose of this study was to understand the mechanism of edema formation and inflammation in airway walls. Therefore, we sought first to determine the normal bronchial venous drainage pathways. In anesthetized, ventilated, open-chest sheep we measured the relative distribution of 51Cr-labeled red blood cells to the right and left ventricles after injection into the bronchial artery ( n = 7). Using this information, we then studied the kinetics of leukocytes in the bronchial vascular bed. We measured the extraction of111In-labeled neutrophils during their first pass through the microvasculature after injection into the bronchial artery or right ventricle ( n= 6). In the first set of experiments, we found >85% of the systemic blood flow to the lung returns to the left ventricle. In the second set of experiments, we found that extraction of neutrophils in the bronchial vasculature (50–60%) was less ( P < 0.05) than that in the pulmonary vasculature (80%). This finding may be explained by differences in the anatomy and/or hydrodynamic dispersal forces between the pulmonary and bronchial vascular beds or may reflect sequestration of neutrophils within the pulmonary microvasculature while traversing bronchial-to-pulmonary anastomotic pathways.

scholarly journals Anomalous Venous Blood Flow and Iron Deposition in Multiple Sclerosis

2009 ◽  
Vol 29 (12) ◽  
pp. 1867-1878 ◽  
Author(s):  
Ajay Vikram Singh ◽  
Paolo Zamboni
Keyword(s):  
Multiple Sclerosis ◽  
Blood Flow ◽  
Iron Overload ◽  
Neurodegenerative Disorders ◽  
Imaging Techniques ◽  
Venous Blood ◽  
Unknown Origin ◽  
Venous Drainage ◽  
Iron Deposition ◽  
Venous Blood Flow

Multiple sclerosis (MS) is primarily an autoimmune disorder of unknown origin. This review focuses iron overload and oxidative stress as surrounding cause that leads to immunomodulation in chronic MS. Iron overload has been demonstrated in MS lesions, as a feature common with other neurodegenerative disorders. However, the recent description of chronic cerebrospinal venous insufficiency (CCSVI) associated to MS, with significant anomalies in cerebral venous outflow hemodynamics, permit to propose a parallel with chronic venous disorders (CVDs) in the mechanism of iron deposition. Abnormal cerebral venous reflux is peculiar to MS, and was not found in a miscellaneous of patients affected by other neurodegenerative disorders characterized by iron stores, such as Parkinson's, Alzheimer's, amyotrophic lateral sclerosis. Several recently published studies support the hypothesis that MS progresses along the venous vasculature. The peculiarity of CCSVI-related cerebral venous blood flow disturbances, together with the histology of the perivenous spaces and recent findings from advanced magnetic resonance imaging techniques, support the hypothesis that iron deposits in MS are a consequence of altered cerebral venous return and chronic insufficient venous drainage.

Superior venous drainage in the “LifeBox”: a portable extracorporeal oxygenator with a self-expanding venous cannula

Perfusion ◽  
2010 ◽  
Vol 25 (4) ◽  
pp. 211-215 ◽  
Author(s):  
Denis Berdajs ◽  
Frank Born ◽  
Monique Crosset ◽  
Judith Horisberger ◽  
Andreas Künzli ◽  
...  
Keyword(s):  
Blood Flow ◽  
Jugular Vein ◽  
Venous Drainage ◽  
External Jugular Vein ◽  
The Self ◽  
Patient Transport ◽  
Drainage Device ◽  
Venous Cannula ◽  
The Common ◽  
Line Pressure

Background: In an experimental setting, the performance of the LifeBox, a new portable extracorporeal membrane oxygenator (ECMO) system suitable for patient transport, is presented. Standard rectilinear percutaneous cannulae are normally employed for this purpose, but have limited flow and pressure delivery due to their rigid structure. Therefore, we aimed to determine the potential for flow increase by using self-expanding venous cannulae. Methods: Veno-arterial bypass was established in three pigs (40.6±5.1 kg). The venous line of the cardiopulmonary bypass was established by cannulation of the external jugular vein. The arterial side of the circulation was secured by cannulation of the common carotid artery. Two different venous cannulae (SmartCanula 18/36F 430mm and Biomedicus 19F) were examined for their functional integrity when used in conjunction with the centrifugal pump (500-3000 RPM) of the LifeBox system. Results: At 1500, 2000, 2500, and 3000 RPM, the blood flow increased steadily for each cannula, but remained higher in the self-expanding cannula. That is, the 19F rectilinear cannula achieved a blood flow of 0.93±0.14, 1.47±0.37, 1.9±0.68, and 1.5±0.9 l/min, respectively, and the 18/36F self-expanding cannula achieved 1.1±0.1, 1.9±0.33, 2.8±0.39 and 3.66±0.52 l/min. However, when tested for venous line pressure, the standard venous cannula achieved -29±10.7mmHg while the self-expanding cannula achieved -13.6 ±4.3mmHg at 1500 RMP. As the RPM increased from 2500 to 3000, the venous line pressure accounted for −141.9±20 and −98±7.3mmHg for the 19F rectilinear cannula and -30.6±6.4 and -45±11.6mmHg for the self-expanding cannula. Conclusion: The self-expanding cannula exhibited superior venous drainage ability when compared to the performance of the standard rectilinear cannula with the use of the LifeBox. The flow rate achieved was approximately 40% greater than the standard drainage device, with a maximal pump flow recorded at 4.3l/min.

Surgical Management of Infants with Complex Cardiac Anomalies Associated with Reduced Pulmonary Blood Flow and Total Anomalous Pulmonary Venous Drainage

1987 ◽  
Vol 43 (2) ◽  
pp. 207-211 ◽  
Author(s):  
Serafin Y. DeLeon ◽  
Samuel S. Gidding ◽  
Michel N. Ilbawi ◽  
Farouk S. Idriss ◽  
Alexander J. Muster ◽  
...  
Keyword(s):  
Blood Flow ◽  
Surgical Management ◽  
Pulmonary Blood Flow ◽  
Venous Drainage ◽  
Cardiac Anomalies ◽  
Anomalous Pulmonary Venous Drainage

scholarly journals Coupling between arterial and venous cerebral blood flow during postural change

2016 ◽  
Vol 311 (6) ◽  
pp. R1255-R1261 ◽  
Author(s):  
Shigehiko Ogoh ◽  
Takuro Washio ◽  
Hiroyuki Sasaki ◽  
Lonnie G. Petersen ◽  
Niels H. Secher ◽  
...  
Keyword(s):  
Blood Flow ◽  
Healthy Subjects ◽  
Internal Carotid ◽  
Jugular Vein ◽  
Venous Drainage ◽  
Postural Change ◽  
Venous Outflow ◽  
Venous Flow ◽  
End Tidal ◽  
The Brain

In supine humans the main drainage from the brain is through the internal jugular vein (IJV), but the vertebral veins (VV) become important during orthostatic stress because the IJV is partially collapsed. To identify the effect of this shift in venous drainage from the brain on the cerebral circulation, this study addressed both arterial and venous flow responses in the “anterior” and “posterior” parts of the brain when nine healthy subjects (5 men) were seated and flow was manipulated by hyperventilation and inhalation of 6% carbon dioxide (CO2). From a supine to a seated position, both internal carotid artery (ICA) and IJV blood flow decreased ( P = 0.004 and P = 0.002), while vertebral artery (VA) flow did not change ( P = 0.348) and VV flow increased ( P = 0.024). In both supine and seated positions the ICA response to manipulation of end-tidal CO2 tension was reflected in IJV ( r = 0.645 and r = 0.790, P < 0.001) and VV blood flow ( r = 0.771 and r = 0.828, P < 0.001). When seated, the decrease in ICA blood flow did not affect venous outflow, but the decrease in IJV blood flow was associated with the increase in VV blood flow ( r = 0.479, P = 0.044). In addition, the increase in VV blood flow when seated was reflected in VA blood flow ( r = 0.649, P = 0.004), and the two flows were coupled during manipulation of the end-tidal CO2 tension (supine, r = 0.551, P = 0.004; seated, r = 0.612, P < 0001). These results support that VV compensates for the reduction in IJV blood flow when seated and that VV may influence VA blood flow.

VENOUS DRAINAGE AND FUNCTIONAL CONTROL OF THE CANINE PROSTATE GLAND

1977 ◽  
Vol 75 (1) ◽  
pp. 105-108 ◽  
Author(s):  
C. B. DHABUWALA ◽  
C. G. PIERREPOINT
Keyword(s):  
Blood Flow ◽  
Intravenous Injection ◽  
Prostate Gland ◽  
Venous Drainage ◽  
Venous System ◽  
Prostatic Urethra ◽  
Post Mortem ◽  
Data Support ◽  
Retrograde Blood Flow ◽  
Functional Control

The venous drainage of the canine prostate gland has been studied in nine dogs after post-mortem intravenous injection of a coloured suspension of latex. A submucosal cavernous plexus of the prostatic urethra continuous with that of the penis, and a previously unnamed vessel that drains this plexus into the prostatico-vesical vein are described. The eferential vein was found to open variably, but always into the prostatic venous system. The data support the concept that a very small retrograde blood flow would take androgenrich blood from the deferential vein into the prostate gland.

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