Changes of the hepatic subcapsular blood flow in a case of high-grade retroperitoneal liposarcoma: what to expect?

2021 ◽  
Vol 14 (1) ◽  
pp. e237317
Author(s):  
Nádia Silva ◽  
Filipe Veloso Gomes ◽  
João Santos Coelho ◽  
Tiago Bilhim
Keyword(s):  
Blood Flow ◽  
Female Patient ◽  
Superior Vena ◽  
Vena Cava ◽  
Falciform Ligament ◽  
High Grade ◽  
External Compression ◽  
Retroperitoneal Liposarcoma ◽  
Radiologic Findings ◽  
Early Appearance

Changes of the hepatic subcapsular blood flow with the early appearance of hypervascularity near the falciform ligament are rare radiologic findings. They present most frequently in cases of superior vena cava (SVC) obstruction and are related to the recruitment of the cavo-mammary-phrenic–hepatic–capsule–portal and the cavo-superficial–umbilical–portal pathways. We present the case of a 52-year-old female patient with an highly aggressive retroperitoneal liposarcoma with SVC obstruction caused by external compression due to a mediastinal metastatic mass. The patient exhibited no symptoms of SVC obstruction due to the collateral cavo-portal pathways.

Regional pulmonary blood flow during 96 hours of hypoxia in conscious sheep

1986 ◽  
Vol 61 (6) ◽  
pp. 2136-2143 ◽  
Author(s):  
D. C. Curran-Everett ◽  
K. McAndrews ◽  
J. A. Krasney
Keyword(s):  
Blood Flow ◽  
Arterial Pressure ◽  
Pulmonary Blood Flow ◽  
Pulmonary Arterial Pressure ◽  
Pressor Response ◽  
Superior Vena ◽  
Acute Hypoxia ◽  
Vena Cava ◽  
Normobaric Hypoxia ◽  
Pulmonary Arterial

The effects of acute hypoxia on regional pulmonary perfusion have been studied previously in anesthetized, artificially ventilated sheep (J. Appl. Physiol. 56: 338–342, 1984). That study indicated that a rise in pulmonary arterial pressure was associated with a shift of pulmonary blood flow toward dorsal (nondependent) areas of the lung. This study examined the relationship between the pulmonary arterial pressor response and regional pulmonary blood flow in five conscious, standing ewes during 96 h of normobaric hypoxia. The sheep were made hypoxic by N2 dilution in an environmental chamber [arterial O2 tension (PaO2) = 37–42 Torr, arterial CO2 tension (PaCO2) = 25–30 Torr]. Regional pulmonary blood flow was calculated by injecting 15-micron radiolabeled microspheres into the superior vena cava during normoxia and at 24-h intervals of hypoxia. Pulmonary arterial pressure increased from 12 Torr during normoxia to 19–22 Torr throughout hypoxia (alpha less than 0.049). Pulmonary blood flow, expressed as %QCO or ml X min-1 X g-1, did not shift among dorsal and ventral regions during hypoxia (alpha greater than 0.25); nor were there interlobar shifts of blood flow (alpha greater than 0.10). These data suggest that conscious, standing sheep do not demonstrate a shift in pulmonary blood flow during 96 h of normobaric hypoxia even though pulmonary arterial pressure rises 7–10 Torr. We question whether global hypoxic pulmonary vasoconstriction is, by itself, beneficial to the sheep.

scholarly journals Thrombogenic Catheter-Associated Superior Vena Cava Syndrome

2013 ◽  
Vol 2013 ◽  
pp. 1-3 ◽  
Author(s):  
Imran Shaikh ◽  
Kenneth Berg ◽  
Nicholas Kman
Keyword(s):  
Superior Vena Cava ◽  
Superior Vena Cava Syndrome ◽  
Superior Vena ◽  
Vena Cava ◽  
Signs And Symptoms ◽  
External Compression ◽  
Central Lines ◽  
Svc Syndrome ◽  
History Of ◽  
Vena Cava Syndrome

Superior vena cava syndrome has historically been associated with malignancy. With the increasing use of indwelling central lines, catheters, and pacemakers in the past decade, there have been an increasing number of cases associated with thrombosis rather than by direct external compression. Patients presenting to the ED with an acute process of SVC syndrome need to be assessed in a timely fashion. Computed tomography angiography (CTA) or magnetic resonance angiogram (MRA) are superb modalities for diagnosis and can quickly be used in the ED. Treatment is oriented towards the underlying cause of the syndrome. In cases of thrombogenic catheter-associated SVC syndrome, anticoagulation is the mainstay of treatment. We present a case report and discussion of a 56-year-old male with a history of metastatic colorectal cancer and an indwelling central venous port with acute signs and symptoms of superior vena cava syndrome.

A Computational Pulsatile Model of the Bidirectional Cavopulmonary Anastomosis: The Influence of Pulmonary Forward Flow

1996 ◽  
Vol 118 (4) ◽  
pp. 520-528 ◽  
Author(s):  
Francesco Migliavacca ◽  
Marc R. de Leval ◽  
Gabriele Dubini ◽  
Riccardo Pietrabissa
Keyword(s):  
Blood Flow ◽  
Pulmonary Artery ◽  
Superior Vena Cava ◽  
Superior Vena ◽  
Main Pulmonary Artery ◽  
Vena Cava ◽  
Similar Distribution ◽  
Pulsatile Blood Flow ◽  
Cavopulmonary Anastomosis ◽  
Bidirectional Cavopulmonary Anastomosis

The bidirectional cavopulmonary anastomosis (BCPA or bidirectional Glenn) is an operation to treat congenital heart diseases of the right heart by diverting the systemic venous return from the superior vena cava to both lungs. The main goal is to provide the correct perfusion to both lungs avoiding an excessive increase in systemic venous pressure. One of the factors which can affect the clinical outcome of the surgically reconstructed circulation is the amount of pulsatile blood flow coming from the main pulmonary artery. The purpose of this work is to analyse the influence of this factor on the BCPA hemodynamics. A 3-D finite element model of the BCPA has been developed to reproduce the flow of the surgically reconstructed district. Geometry and hemodynamic data have been taken from angiocardiogram and catheterization reports, respectively. On the basis of the developed 3-D model, four simulations have been performed with increasing pulsatile blood flow rate from the main pulmonary artery. The results show that hemodynamics in the pulmonary arteries are greatly influenced by the amount of flow through the native main pulmonary artery and that the flow from the superior vena cava allows to have a similar distribution of the blood to both lungs, with a little predilection for the left side, in agreement with clinical postoperative data.

scholarly journals Use of Superior Vena Cava-Right Pulmonary Artery Anastomosis in Congenital Heart Disease with Decreased Pulmonary Blood Flow

Circulation ◽  
1969 ◽  
Vol 40 (6) ◽  
pp. 777-784 ◽  
Author(s):  
IRWIN B. BORUCHOW ◽  
THOMAS D. BARTLEY ◽  
LARRY P. ELLIOTT ◽  
MYRON W. WHEAT ◽  
L. JEROME KROVETZ ◽  
...  
Keyword(s):  
Congenital Heart Disease ◽  
Blood Flow ◽  
Heart Disease ◽  
Pulmonary Artery ◽  
Superior Vena Cava ◽  
Pulmonary Blood Flow ◽  
Congenital Heart ◽  
Superior Vena ◽  
Vena Cava ◽  
Right Pulmonary Artery

scholarly journals The Methodology of Doppler-Derived Central Blood Flow Measurements in Newborn Infants

2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Koert A. de Waal
Keyword(s):  
Blood Flow ◽  
Doppler Ultrasound ◽  
Superior Vena ◽  
Ductus Arteriosus ◽  
Newborn Infants ◽  
Vena Cava ◽  
Left Ventricular ◽  
Flow Measurements ◽  
General Guide ◽  
Blood Flow Measurements

Central blood flow (CBF) measurements are measurements in and around the heart. It incorporates cardiac output, but also measurements of cardiac input and assessment of intra- and extracardiac shunts. CBF can be measured in the central circulation as right or left ventricular output (RVO or LVO) and/or as cardiac input measured at the superior vena cava (SVC flow). Assessment of shunts incorporates evaluation of the ductus arteriosus and the foramen ovale. This paper describes the methodology of CBF measurements in newborn infants. It provides a brief overview of the evolution of Doppler ultrasound blood flow measurements, basic principles of Doppler ultrasound, and an overview of all used methodology in the literature. A general guide for interpretation and normal values with suggested cutoffs of CBFs are provided for clinical use.

Hemodynamics Characteristics of a Four-Way Right-Atrium Bypass Connector

2017 ◽  
Author(s):  
Elizabeth Mack ◽  
Alexandrina Untaroiu
Keyword(s):  
Blood Flow ◽  
Superior Vena Cava ◽  
Right Atrium ◽  
Superior Vena ◽  
Pulmonary Arteries ◽  
Vena Cava ◽  
Design Parameters ◽  
Patient Specific ◽  
Optimal Size ◽  
The Right

Currently, the surgical procedure followed by the majority of cardiac surgeons to address right ventricular dysfunction is the Fontan procedure, which connects the superior and inferior vena cava directly to the left and right pulmonary arteries bypassing the right atrium. However, this is not the most efficient configuration from a hemodynamics perspective. The goal of this study is to develop a patient-specific 4-way connector to bypass the dysfunctional right ventricle and augment the pulmonary circulation. The 4-way connector is intended to channel the blood flow from the inferior and superior vena cava directly to the right and left pulmonary arteries. By creating a connector with proper hemodynamic characteristics, one can control the jet flow interactions between the inferior and superior vena cava and streamline the flow towards the right and left pulmonary arteries. In this study the focus is on creating a system that can identify the optimal configuration for the 4-way connector for patients from 0–20 years of age. A platform is created in ANSYS that utilizes the DOE function to minimize power-loss and blood damage propensity in the connector based on junction geometries. A CFD model is created to simulate the blood flow through the connector. Then the geometry of the bypass connector is parameterized for DOE process. The selected design parameters include inlet and outlet diameters, radius at the intersection, and length of the connector pathways. The chosen range for each geometric parameter is based on the relative size of the patient’s arteries found in the literature. It was confirmed that as the patient’s age and artery size change, the optimal size and shape of the connector also changes. However, the corner radius did not decrease at the same rate as the opening diameters. This means that creating different sized connectors is not just a matter of scaling the original connector to match the desired opening diameter. However, it was found that power losses within the connector decrease and average and maximum blood traversal time through the connector increased for increasing opening radius. This information could be used to create a more specific relationship between the opening radius and the flow characteristics. So in order to create patient specific connectors, either a new more complicated trend needs to be found or an optimization program would need to be run on each patient’s specific geometry when they need a new connector.

scholarly journals Pharmacological management of low blood flow state in less than 28weeks neonate.

2021 ◽  
Author(s):  
Femi Adeniyi ◽  
Kunle Oyedokun ◽  
Adeniyi Ajiboye ◽  
Sanjeev Rath
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Pharmacological Treatment ◽  
Superior Vena ◽  
Ductus Arteriosus ◽  
Vena Cava ◽  
Low Flow ◽  
Systemic Resistance ◽  
Preterm Neonates ◽  
Flow State

low blood flow state is defined as insufficient cardiac output to maintain adequate cellular metabolism at the organ level. A low blood flow state can be measured by reduced organ perfusion, such as reduced superior vena cava flow[1,2] or high resistance flow in superior mesenteric doppler scan [3]. The combination of capillary refill time of greater than 4 seconds and serum lactate greater than 4 mmol/litre has 97% sensitivity of identifying low blood flow state [4]. In the presence of the above markers of a low blood flow state, the blood pressure may be normal or high in the first 48hours of life due to high systemic resistance [5]. Therefore, high, or normal blood pressure should be interpreted with great caution. CONCLUSIONThe pharmacological treatment of a low blood flow state should be guided by thorough clinical assessment. The prophylaxis or stress dose hydrocortisone treatment of low flow state is gaining grounds mainly when there is evidence of adrenal insufficiency. The choice and titration of pharmacological treatment should be guided by functional echocardiography. The use of Dobutamine as first-line treatment is advised when myocardia dysfunction on echocardiography is noted.Milrinone use is reserved for extreme preterm neonates with myocardia dysfunction before patent ductus arteriosus ligation. Dopamine and noradrenaline remain the commonly used first and second-line vasopressors, respectively, to manage low blood flow states secondary to poor vasomotor resistance.

scholarly journals OPTIMAL CONTROL THEORY APPLIED TO A DIFFERENCE EQUATION MODEL FOR CARDIOPULMONARY RESUSCITATION

2005 ◽  
Vol 15 (10) ◽  
pp. 1519-1531 ◽  
Author(s):  
EUNOK JUNG ◽  
SUZANNE LENHART ◽  
VLADIMIR PROTOPOPESCU ◽  
CHARLES F. BABBS
Keyword(s):  
Optimal Control ◽  
Blood Flow ◽  
Cardiopulmonary Resuscitation ◽  
Superior Vena ◽  
Vena Cava ◽  
Circulation Model ◽  
Adjoint System ◽  
State Variables ◽  
Time Step ◽  
Current Time

The techniques of optimal control are applied to a validated blood circulation model of cardiopulmonary resuscitation (CPR), consisting of a system of seven difference equations. In this system, the nonhomogeneous forcing term is the externally applied chest pressure acting as the "control". We seek to maximize the blood flow, as measured by the pressure differences between the thoracic aorta and the superior vena cava. The new aspect in this application is that the control values from the two previous time steps are used to calculate the pressures (state variables) at the current time step. We prove the existence and uniqueness of the optimal control and provide a new CPR strategy, with increased blood flow. The characterization of the optimal control is given in terms of the solutions of the circulation model and of the corresponding adjoint system. The numerical results show a significant increase in the blood flow as compared with standard CPR.

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