scholarly journals Morphometric Analysis of the Aorto-Esophageal Relationship in Swine for Trans-Esophageal Aortic Blood Flow Occlusion

2022 ◽  
Vol 5 (3) ◽  
Author(s):  
Samuel G Savidge ◽  
Hossam Abdou ◽  
Joseph Edwards ◽  
Neerav Patel ◽  
Michael J Richmond ◽  
...  
Keyword(s):  
Blood Flow ◽  
Thoracic Esophagus ◽  
Aortic Blood Flow ◽  
Miniature Swine ◽  
Descending Aorta ◽  
Aortic Blood ◽  
Significant Difference ◽  
Blood Flow Occlusion ◽  
The Mean ◽  
Flow Occlusion

Background Trans-esophageal aortic blood flow occlusion (TEABO) is an emerging technology undergoing laboratory research that offers a strategy for temporary hemorrhage control. The purpose of this study was to evaluate the anatomical relationship between the esophagus and descending thoracic aorta in two breeds of swine to support a porcine model for future TEABO investigations. Methods Thoracoabdominal CT scans were compared in Hanford miniature swine and Yorkshire swine. Measurements were taken at the five vertebral levels proximal to the gastroesophageal junction. Data collected included the distance between the center of the esophagus and the center of the descending aorta, the angle between the vertebral column, descending aorta, and esophagus, and the length the thoracic esophagus travels anteriorly to the descending aorta. Results Ten Hanford swine and ten Yorkshire swine were compared. In Hanford swine, the distal thoracic esophagus travels anteriorly to the descending aorta for a mean distance of 11.5 ± 2.3 cm. In Yorkshire swine, the thoracic esophagus travels to the right of the descending aorta. The mean angle between the vertebral body, descending aorta, and esophagus was 79.6 to 97.8 degrees higher in Hanfords compared to Yorkshires (p<0.0001 at all five vertebral levels compared). The mean distance between the esophagus and descending aorta was 0.2 to 0.6 cm higher in Hanfords compared to Yorkshires with a significant difference found at only two vertebral levels (p=0.01 and p=0.02). Conclusion Hanford miniature swine possess an aorto-esophageal relationship comparable to humans and should be the preferred animal model for TEABO studies.

Use of microspheres in measurement of regional blood flows during +GZ stress

1979 ◽  
Vol 47 (6) ◽  
pp. 1148-1156 ◽  
Author(s):  
M. H. Laughlin ◽  
J. W. Burns ◽  
F. M. Loxsom
Keyword(s):  
Blood Flow ◽  
Regional Blood Flow ◽  
Aortic Pressure ◽  
Aortic Blood Flow ◽  
Miniature Swine ◽  
Blood Flows ◽  
Aortic Blood ◽  
High Acceleration ◽  
Regional Blood Flows ◽  
Aortic Blood Pressure

The use of the radiolabeled microsphere technique for the study of the effects of +GZ acceleration on regional blood flow is examined. A theoretical analysis of the limits of this technique in a high acceleration environment is presented. Chronically implanted, electromagnetic, aortic flow probes were used to determine the relationship between aortic blood flow velocity and +GZ acceleration in conscious adult miniature swine. It was found that conscious straining adult miniature swine, with the assistance of an inflated anti-G suit, are able to compensate quite well to acceleration levels less than or equal to +7 GZ. Exposure to +9 GZ often resulted in unstable cardiovascular states involving relative bradycardia, often progressing to asystole, declining aortic blood pressure, and markedly diminished cardiac outputs approaching zero. It was found that, if aortic pressure and heart rate attain a relatively steady state during acceleration, and if heart level mean aortic pressure is greater than or equal to 100 Torr, the application of the microsphere technique during +GZ acceleration is theoretically valid. This hypothesis was tested using the microsphere technique (9.0 +/- 0.8 microns diam) in conscious miniature swine during exposure to +GZ acceleration. It is concluded that within the defined limits the radiolabeled microsphere technique is as accurate for use during acceleration studies as it is for use in routine laboratory studies.

scholarly journals Exercise and Repeated Testing Improves Accuracy of Laser Doppler Assessment of Microvascular Function Following Shortened (1-minute) Blood Flow Occlusion

2016 ◽  
Vol 23 (4) ◽  
pp. 293-300 ◽  
Author(s):  
Brian D. Tran ◽  
Abraham Chiu ◽  
Charlene Tran ◽  
Danica Rose Rogacion ◽  
Nicole Tfaye ◽  
...  
Keyword(s):  
Blood Flow ◽  
Microvascular Function ◽  
Laser Doppler ◽  
Repeated Testing ◽  
Blood Flow Occlusion ◽  
Flow Occlusion

COMPUTATIONS OF PULSATILE AORTIC BLOOD FLOW PROBLEMS ON PARALLEL COMPUTERS

2003 ◽  
Vol 15 (03) ◽  
pp. 109-114
Author(s):  
YANG-YAO NIU ◽  
SHOU-CHENG TCHENG
Keyword(s):  
Blood Flow ◽  
Stokes Equations ◽  
Computing Time ◽  
Time Integration ◽  
Parallel Computer ◽  
Aortic Blood Flow ◽  
Pc Cluster ◽  
Flow Problems ◽  
Aortic Blood ◽  
Speed Up

In this study, a parallel computing technology is applied on the simulation of aortic blood flow problems. A third-order upwind flux extrapolation with a dual-time integration method based on artificial compressibility solver is used to solve the Navier-Stokes equations. The original FORTRAN code is converted to the MPI code and tested on a 64-CPU IBM SP2 parallel computer and a 32-node PC Cluster. The test results show that a significant reduction of computing time in running the model and a super-linear speed up rate is achieved up to 32 CPUs at PC cluster. The speed up rate is as high as 49 for using IBM SP2 64 processors. The test shows very promising potential of parallel processing to provide prompt simulation of the current aortic flow problems.

Blood Flow Occlusion Pressure At Rest And Immediately After A Bout Of Low Load Exercise

2015 ◽  
Vol 47 ◽  
pp. 548
Author(s):  
Scott J. Dankel ◽  
Brian E. Barnett ◽  
Brittany R. Counts ◽  
Allison L. Nooe ◽  
Takashi Abe ◽  
...  
Keyword(s):  
Blood Flow ◽  
Occlusion Pressure ◽  
Low Load ◽  
Blood Flow Occlusion ◽  
Flow Occlusion

Effect of Blood Flow Occlusion on Laser Hyperthermia for Liver Metastases

2002 ◽  
Vol 103 (2) ◽  
pp. 165-174 ◽  
Author(s):  
V. Muralidharan ◽  
C. Malcontenti-Wilson ◽  
Chris Christophi
Keyword(s):  
Blood Flow ◽  
Liver Metastases ◽  
Laser Hyperthermia ◽  
Blood Flow Occlusion ◽  
Flow Occlusion

S-nitroso-albumin carries a thiol-labile pool of nitric oxide, which causes venodilation in the rat

2005 ◽  
Vol 289 (2) ◽  
pp. H916-H923 ◽  
Author(s):  
Nelson N. Orie ◽  
Patrick Vallance ◽  
Dean P. Jones ◽  
Kevin P. Moore
Keyword(s):  
Nitric Oxide ◽  
Molecular Weight ◽  
Blood Flow ◽  
Vascular Function ◽  
Low Molecular Weight ◽  
Aortic Blood Flow ◽  
Hemodynamic Effects ◽  
Rapid Decomposition ◽  
Aortic Blood

It is now established that S-nitroso-albumin (SNO-albumin) circulates at low nanomolar concentrations under physiological conditions, but concentrations may increase to micromolar levels during disease states (e.g., cirrhosis or endotoxemia). This study tested the hypothesis that high concentrations of SNO-albumin observed in some diseases modulate vascular function and that it acts as a stable reservoir of nitric oxide (NO), releasing this molecule when the concentrations of low-molecular-weight thiols are increased. SNO-albumin was infused into rats to increase the plasma concentration from <50 nmol/l to ∼4 μmol/l. This caused a 29 ± 6% drop in blood pressure, 20 ± 4% decrease in aortic blood flow, and a 25 ± 14% reduction of renal blood flow within 10 min. These observations were in striking contrast to those of an infused arterial vasodilator (hydralazine), which increased aortic blood flow, and suggested that SNO-albumin acts primarily as a venodilator in vivo. This was confirmed by the observations that glyceryl trinitrate (a venodilator) led to similar hemodynamic changes and that the hemodynamic effects of SNO-albumin are reversed by infusion of colloid. Infusion of N-acetylcysteine into animals with artificially elevated plasma SNO-albumin concentrations led to the rapid decomposition of SNO-albumin in vivo and reproduced the hemodynamic effects of SNO-albumin infusion. These data demonstrate that SNO-albumin acts primarily as a venodilator in vivo and represents a stable reservoir of NO that can release NO when the concentrations of low-molecular-weight thiols are elevated.

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