Numerical Investigation of Blood Flow Characteristics through Cannulated Aorta

2019 ◽  
Vol 43 ◽  
pp. 28-38
Author(s):  
Dheeman Bhuyan ◽  
P. Ramesh Babu ◽  
Jyoti Prasad Kalita
Keyword(s):  
Blood Flow ◽  
Aortic Wall ◽  
Flow Characteristics ◽  
Physiological Flow ◽  
Heart Lung Machine ◽  
Flow Through ◽  
Cardio Pulmonary Bypass ◽  
Pulmonary Bypass ◽  
Multiple Morbidities ◽  
Lung Machine

Cannulation of the aorta is done in order to provide oxygenation and circulatory function through the use of the heart lung machine during cardio-pulmonary bypass (CPB). The nature of the blood flow through the aorta and its ramifications during CPB is mostly linear as compared to the physiological flow, which is pulsatile in nature. This leads to the development of multiple morbidities caused by the development of emboli and atheromas. Perioperative postoperative care is necessitated by these conditions. As such the understanding of the blood flow characteristics is necessitated in order to effectively prevent the formation of emboli and to prevent the "Sandblasting" effect. The authors in this work seek to investigate the nature of blood flow through the aorta under such circumstances. The results obtained show the nature of blood flow in the cannulated aorta as well as the optimum angle of placement of the cannula with respect to the aortic wall.

FRAGMIN VS HEPARIN AT RECYCLING OE HUMAN BLOOD IN HEART-LUNG MACHINE (HLM)

1987 ◽  
Author(s):  
L Bagge ◽  
E Holmer ◽  
S O Nystroöm ◽  
H Tydeén ◽  
T Wahlberg
Keyword(s):  
Platelet Activity ◽  
Donor Blood ◽  
Artificial System ◽  
Thrombin Inhibition ◽  
Clinical Level ◽  
Heart Lung Machine ◽  
Cardio Pulmonary Bypass ◽  
Pulmonary Bypass ◽  
Dose Dependent ◽  
Lung Machine

During cardio-pulmonary bypass (CPB), Heparin inhibits EXa (EXal), thrombin and platelet activity and is also reported to induce fibrinolysis. Eragmin (Erag) has 25% thrombin inhibition capacity as related to that of Heparin (Hep). An in_vitro study was performed to compare Frag with Hep by circulating blood in a pure artificial system. In 20 experiments, 400 ml of freshly collected blood with Frag or Hep were recycled for 2 h. HLM was primed with 400 ml of Ringeracetate. Blood sampling: donor, blood pack and every 20 min from the oxygenator. V_a£i£ble£/jassay/:ACT/Hemochron/5 APTT , TT and NT/Nyegaard/;FXaI, FVIII and ATIiT t"ATA)/amydolytic/; AT 111 (ATAg) and vWF/IEP/;Plasminogen (Pig) and albumine/immuno-diffusion/;FDP/Wellcome/;Platelet function/Adeplat S/;Fibrinogen (Fbg)/clottable/;Hemolysis (HL)/photometric/; (β -Thromboglobulin ((βTG)/RTA/;EVF, Hb, platelet count (PC) and Leucocyte count (LC)/ conventional). Corrections for hemo-/plasma dilutions were calculated. Dosages (n): Frag: 750 (1), 1500 (3), 2100 (4), 2500 (4) FXal-U (U); Hep: 1000 (3), 1500 (6) IU clinical level. Clotting only occurred at Frag 750 (1) and 1500 (2) U, when ACT, APTT, FVIII, Fbg and ATA were significantly lowered. Generally, PC fell 75% during the recycling, while PF was constant'∼20% and (βTG increased. Neither presence of FDP nor Pig consumption were detected. FXal, ACT, APTT, TT and NT were dose dependent for both drugs. ATA was directly dose-related to Frag but inversely to Hep. LC decreased with the Frag-dose but inversely to that of Hep. HL increased generally. Several proteins increased (clotting excl): Fbg 30%, ATAg 25%, ATA 45?o and vWF 60%. Conclusions. Prevention of clotting required about the double dosage of Frag. Shortened ACT and APTT predicted clotting while the levels of FXal, TT and NT did not. Thus, an effective thrombin inhibition is needed under this conditions. Consumptions of FVIII, Fbg and ATA but no further drop in PC at clotting, indicate weak platelet aggregation involvement. Absence of fibrinolytic signs supports that the fibrinolysis seen at CPB, is not a genuine effect of Hep (or Frag). Increases in some proteins may be caused by cytolysis. The rise in vWF is probably due to release from platelet surfaces.

Direct Numerical Simulation of Cellular Blood Flow Through a Model Arteriole Bifurcation

2010 ◽  
Author(s):  
Daniel A. Reasor ◽  
Jonathan R. Clausen ◽  
Cyrus K. Aidun
Keyword(s):  
Numerical Simulation ◽  
Blood Flow ◽  
Direct Numerical Simulation ◽  
Volume Fraction ◽  
Flow Characteristics ◽  
Particle Level ◽  
Suspension Dynamics ◽  
Flow Through ◽  
Fahraeus Effect ◽  
The Continuum

Blood is composed of a suspension of red blood cells (RBCs) suspended in plasma, and the presence of the RBCs substantially changes the flow characteristics and rheology of these suspensions. The viscosity of blood varies with the hematocrit (volume fraction of RBCs), which is a result not seen in Newtonian fluids. Additionally, RBCs are deformable, which can alter suspension dynamics. Understanding the physics in these flows requires accurately simulating the suspended phase to recover the microscale, and a subsequent analysis of the rheology to ascertain the continuum-level effects caused by the changes at the particle level. The direct numerical simulation of blood flow including RBC migration effects has the capability to resolve the Fåhraeus effect of observing low hematocrit values near walls, the subsequent cell-depleted layer, and the presence of velocity profile blunting due to the distribution of RBCs.

Blood flow analysis in tapered stenosed arteries with pseudoplastic characteristics

2014 ◽  
Vol 07 (06) ◽  
pp. 1450065 ◽  
Author(s):  
Noreen Sher Akbar ◽  
S. Nadeem
Keyword(s):  
Blood Flow ◽  
Flow Analysis ◽  
Flow Characteristics ◽  
Shearing Stress ◽  
Tapered Artery ◽  
Impedance Wall ◽  
Flow Through ◽  
Blood Flow Analysis ◽  
Parameters Of Interest ◽  
Perturbation Solutions

In this paper, the blood flow through a tapered artery with a stenosis by considering axially non-symmetric but radially symmetric mild stenosis on blood flow characteristics is analyzed, assuming the flow is steady and blood is treated as Williamson fluid. Perturbation solutions have been evaluated for velocity, resistance impedance, wall shear stress and shearing stress at the stenosis throat. The graphical results of different type of tapered arteries (i.e. converging tapering, diverging tapering, non-tapered artery) have been examined for different parameters of interest.

scholarly journals Numerical Simulation of Magnetohydrodynamic Influences on Casson Model for Blood Flow through an Overlapping Stenosed Artery

2021 ◽  
pp. 1016-1024
Author(s):  
Ahmed Bakheet ◽  
Esam A. Alnussairy
Keyword(s):  
Blood Flow ◽  
Flow Characteristics ◽  
Correction Method ◽  
Casson Fluid ◽  
Governing Equations ◽  
Finite Difference Technique ◽  
Stenosed Artery ◽  
Flow Phenomena ◽  
Flow Through ◽  
Unsteady Blood Flow

Magnetohydrodynamic (MHD) effects of unsteady blood flow on Casson fluid through an artery with overlapping stenosis were investigated. The nonlinear governing equations accompanied by the appropriate boundary conditions were discretized and solved based on a finite difference technique, using the pressure correction method with MAC algorithm. Moreover, blood flow characteristics, such as the velocity profile, pressure drop, wall shear stress, and patterns of streamlines, are presented graphically and inspected thoroughly for understanding the blood flow phenomena in the stenosed artery.

scholarly journals On Two-Fluid Blood Flow through Stenosed Artery with Permeable Wall

2014 ◽  
Vol 11 (1-2) ◽  
pp. 39-45
Author(s):  
Rupesh K. Srivastav ◽  
V. P. Srivastava
Keyword(s):  
Blood Flow ◽  
Present Model ◽  
Fluid Model ◽  
Flow Characteristics ◽  
Mechanical Study ◽  
Stenosed Artery ◽  
Flow Through ◽  
Flowing Blood ◽  
Two Fluid Model ◽  
Two Fluid

The present investigation concerns the fluid mechanical study on the effects of the permeability of the wall through an axisymmetric stenosis in an artery assuming that the flowing blood is represented by a two-fluid model. The expressions for the blood flow characteristics, the impedance, the wall shear stress distribution in the stenotic region and the shearing stress at the stenosis throat have been derived. Results for the effects of permeability as well as of the peripheral layer on these blood flow characteristics are quantified through numerical computations and presented graphically and discussed comparatively to validate the applicability of the present model.

scholarly journals A Macroscopic Two-Phase Blood Flow Through a Stenosed Artery with Permeable Wall

2013 ◽  
Vol 10 (1) ◽  
pp. 1-9
Author(s):  
Amit Medhavi
Keyword(s):  
Blood Flow ◽  
Flow Characteristics ◽  
Shearing Stress ◽  
Critical Height ◽  
Two Phase ◽  
Wall Shear Stress Distribution ◽  
Mechanical Study ◽  
Stenosed Artery ◽  
Flow Through ◽  
Flowing Blood

The present paper concerns with the fluid mechanical study on the effects of the permeability of the wall through an overlapping stenosis in an artery assuming that the flowing blood is represented by a macroscopic two-phase model. The expressions for the blood flow characteristics, the impedance, the wall shear stress distribution in the stenotic region, shearing stress at the stenosis throats and at the stenosis critical height have been derived. Results for the effects of permeability as well as of hematocrit on these blood flow characteristics are shown graphically and discussed briefly.

Mixed convection analysis for blood flow through arteries on Williamson fluid model

2015 ◽  
Vol 08 (04) ◽  
pp. 1550045 ◽  
Author(s):  
Noreen Sher Akbar
Keyword(s):  
Blood Flow ◽  
Mixed Convection ◽  
Fluid Model ◽  
Flow Characteristics ◽  
Williamson Fluid ◽  
Tapered Artery ◽  
Impedance Wall ◽  
Different Types ◽  
Flow Through ◽  
Perturbation Solutions

In this paper, the blood flow through a tapered artery with a stenosis by considering axially non-symmetric but radially symmetric mild stenosis on blood flow characteristics is analyzed, assuming the flow is steady and blood is treated as Williamson fluid. The effects of mixed convection heat and mass transfer are also carried out. Perturbation solutions have been calculated for velocity, temperature, concentration, resistance impedance, wall shear stress and shearing stress at the stenosis throat. The graphical results of different types of tapered arteries (i.e. converging tapering, diverging tapering, non-tapered artery) have been examined for different parameters of interest. Streamlines have been plotted at the end of the paper.

scholarly journals The Effect of Vacuum on Venous Drainage: an Experimental Evaluation on Pediatric Venous Cannulas and Tubing Systems

2014 ◽  
Vol 52 (196) ◽  
pp. 960-966 ◽  
Author(s):  
Vladimiro L Vida ◽  
A Bhattarai ◽  
Simone Speggiorin ◽  
Fabio Zanella ◽  
Giovanni Stellin
Keyword(s):  
Experimental Study ◽  
Blood Flow ◽  
Cardiopulmonary Bypass ◽  
Venous Return ◽  
Venous Drainage ◽  
Open Circuit ◽  
Wall Suction ◽  
Starting Point ◽  
Cardio Pulmonary Bypass ◽  
Pulmonary Bypass

Introduction: To observe how vacuum assisted venous drainage (VAVD) may influence the flow in a cardiopulmonary bypass circuit with different size of venous lines and cannulas. Methods: The experimental circuit was assembled to represent the cardiopulmonary bypass circuit routinely used during cardiac surgery. Wall suction was applied directly, modulated and measured into the venous reservoir. The blood flow was measured with a flow-meter positioned on the venous line. The circuit prime volume was replaced with group O date expired re-suspended red cells and Plasmalyte 148 to a hematocrit of 28% to 30%. Results: In an open circuit with gravity siphon venous drain, angled cannulae drain more than straight ones regardless the amount of suction applied to the venous line (16 Fr straight cannula (S) drains 90 ml/min less than a 16 Fr angled (A) with a siphon gravity). The same flow can be obtained with lower cannula size and higher suction (i.e. 12 A with and -30 mmHg). Tables have been created to list how the flow varies according to the size of the cannulas, the size of the venous tubes, and the amount of suction applied to the system. Conclusions: Vacuum assisted venous drainage allows the use of smaller cannulae and venous lines to maintain a good venous return, which is very useful during minimally invasive approaches. The present study should be considered as a preliminary attempt to create a scientific-based starting point for a uniform the use of VAVD. Keywords: cardio-pulmonary bypass; experimental study; vacuum assisted drainage.

scholarly journals Concentric ballooned catheterization to the fractional non-newtonian hybrid nano blood flow through a stenosed aneurysmal artery with heat transfer

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Obaid Ullah Mehmood ◽  
Sehrish Bibi ◽  
Dzuliana F. Jamil ◽  
Salah Uddin ◽  
Rozaini Roslan ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Blood Flow ◽  
Fluid Model ◽  
Flow Characteristics ◽  
Second Grade ◽  
Governing Equations ◽  
Arterial Segment ◽  
Grade Fluid ◽  
Flow Through ◽  
The Impact

AbstractThe current work analyzes the effects of concentric ballooned catheterization and heat transfer on the hybrid nano blood flow through diseased arterial segment having both stenosis and aneurysm along its boundary. A fractional second-grade fluid model is considered which describes the non-Newtonian characteristics of the blood. Governing equations are linearized under mild stenosis and mild aneurysm assumptions. Precise articulations for various important flow characteristics such as heat transfer, hemodynamic velocity, wall shear stress, and resistance impedance are attained. Graphical portrayals for the impact of the significant parameters on the flow attributes have been devised. The streamlines of blood flow have been examined as well. The present finding is useful for drug conveyance system and biomedicines.

scholarly journals Modelling Compressible Blood Flow with Slip in a Constricted Rectangular Flow Domain

2021 ◽  
Author(s):  
Matthew DeClerico
Keyword(s):  
Blood Flow ◽  
Numerical Solutions ◽  
Rectangular Channel ◽  
Flow Characteristics ◽  
Navier Stokes ◽  
Rectangular Microchannel ◽  
Flow Features ◽  
Flow Through ◽  
Linear Differential ◽  
Momentum Integral

The abnormal narrowing of blood vessels is known to affect the characterization of blood flow through these constricted regions. Both theoretical and clinical research has suggested that these changes in flow are associated with cardiovascular related diseases. Analytic, numerical, and particle based methods have been employed to solve the Navier-Stokes momentum integral equations associated with compressible, Newtonian fluid flow. In this thesis, the Karman-Pohlhausen method is used to transform a system of partial differential equations into a single second-order, non-linear differential equation in terms of the density. Numerical solutions are presented and important flow features, including the role of slip and compressibility, are discussed. The choice to use a symmetric rectangular channel, rather than a cylindrical one, is largely motivated by the opportunity to compare the numerical solutions with experimental data collected from a rectangular microchannel. The numerical results also indicate similar trends in the flow characteristics for the rectangular channel as compared to previous results using cylindrical models.

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