PURPOSE: [(18)F]Fluoroazomycin arabinoside (FAZA) is a positron emission tomography (PET) tracer developed to enable identification of hypoxic regions within a tumour. The aims of this study were to determine the optimal kinetic model along with validation of using alternatives to arterial blood sampling for analysing [(18)F]FAZA studies and to assess ...

Aim: The aim of this paper was to analyze the correlation between preoperative imaging features and intraoperative blood loss and transfusion of meningioma in order to explore the possibility of reasonable blood preparation based on the preoperative images. Methods: The data of 93 adults with meningioma having undergone microsurgical operations ...

Long-term, frequent venous access for diagnostic, therapeutic, or research purposes in cats is problematic. Frequent blood sampling over extended periods is necessary for some therapeutic regimes and often required for clinical research in veterinary science. In this paper, we describe the implantation of vascular access ports (VAPs) and assess their ...

OBJECTIVE: This study aims to investigate the distribution of progesterone in venous whole blood, venous serum, fingertip capillary blood, and saliva after its topical application in both cream and gel formulations. METHODS: Ten postmenopausal women were randomized to receive 80 mg of progesterone cream or gel applied daily for 14 ...

We describe an in vitro model of the Fontan circulation with respiration to study subdiaphragmatic venous flow behavior. The venous and arterial connections of a total cavopulmonary connection (TCPC) test section were coupled with a physical lumped parameter (LP) model of the circulation. Intrathoracic and subdiaphragmatic pressure changes associated with ...

During hemodialysis (HD), microemboli develop in the blood circuit of the apparatus. These microemboli can pass through the venous chamber and enter into the patient's circulation. The aim of this study was to investigate whether it is possible to reduce the risk for exposure of microemboli by altering of the ...

BACKGROUND AND PURPOSE:Association between developmental venous anomalies is well known, but remains unexplained. Our aim was to study possible hemodynamic differences around developmental venous anomalies with and without cavernous malformations.MATERIALS AND METHODS:In this prospective study approved by the institutional review board, PWI was performed in 24 patients with 25 DVAs ...

Subduction of intraplate seamounts beneath a geochemically depleted mantle wedge provides a seldom opportunity to trace element recycling and mantle flow in subduction zones. Here we present trace element and Sr, Nd and Pb isotopic compositions of lavas from the central Tonga-Kermadec arc, west of the contemporary Louisville-Tonga trench intersection, ...

In the field of thrombosis and haemostasis, many preanalytical variables influence the results of coagulation assays and measures to limit potential results variations should be taken. To our knowledge, no paper describing the development and maintenance of a haemostasis biobank has been previously published. Our description of the biobank of ...

In Harvey's Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus of 1628, we see the mechanisms of the Circulation worked out more or less in full from the results of experimental demonstration, virtually complete but for the direct visual evidence of a link between the minute final terminations and ...

Previously, we presented the electrolytic inferior vena cava (IVC) model (EIM) during acute venous thrombosis (VT). Here, we present our evaluation of the EIM for chronic VT time points in order to determine whether this model allows for the study of thrombus resolution. C57BL/6 mice (n=191) were utilised. In this ...

Oseltamivir and oseltamivir carboxylate concentrations were measured in venous plasma, venous blood, and capillary blood taken simultaneously from 24 healthy volunteers. Median (range) venous blood to plasma ratios were 1.42 (0.920-1.97) for oseltamivir and 0.673 (0.564-0.814) for oseltamivir carboxylate. Capillary blood/venous plasma ratios were 1.32 (0.737-3.16) for oseltamivir and 0.685 ...

In this study, a new arterial spin labeling (ASL) method with spatially nonselective labeling is introduced, based on the acceleration of flowing spins, which is able to image brain perfusion with minimal contamination from venous signal. This method is termed acceleration-selective ASL (AccASL) and resembles velocity-selective ASL (VSASL), with the ...

The vascular access used in hemodialysis can suffer from numerous complications, which may lead to failure of the access, patient morbidity, and significant costs. The flow field in the region of the venous needle may be a source of damaging hemodynamics and hence adverse effects on the fistula. In this ...

The effects of graduated compression stockings (GCSs) on venous blood velocity were measured in 26 hospitalized medical patients while supine at rest. Peak blood velocity in the right femoral vein was 21.6 cm/s without GCS and 23.0 cm/s with GCS [not significant (NS)]. Peak blood velocity in the right popliteal ...

BACKGROUND: Interaction between vascular wall abnormalities, inflammatory leukocytes, platelets, coagulation factors and hemorheology in the pathogenesis of deep vein thrombosis (DVT) is incompletely understood, requiring well defined animal models of human disease. METHODS AND RESULTS: We subjected male C57BL/6 mice to ligation of the inferior vena cava (IVC) as a ...

BACKGROUND: Exsanguinating haemorrhage is a leading cause of death in severely injured trauma patients. Management includes achieving haemostasis, replacing lost intravascular volume with fluids and blood, and treating coagulopathy. The provision of fluids and blood products is contingent on obtaining adequate vascular access to the patient's venous system. We sought ...

BACKGROUND:: Sufficient perfusion is crucial during and after vascular neurosurgical procedures. Intraoperative ICG-angiography has evolved into a useful tool in aneurysm and arterio-venous-malformation surgery. Semi-quantitative ICG fluorescence analysis Flow 800® may, in addition, lead to a better understanding of local perfusion. OBJECTIVE:: We report the applicability and utility of semi-quantitative ...

Central venous catheterization involves venous puncture and catheter insertion for transfusions. Quantitative conditions that facilitate insertion of the needle, such as the angle and velocity of insertion, have not been clarified. We previously developed a robotic system for guiding the needle along a specified puncture path with high precision and ...

PURPOSE: Sampling of arterial blood for metabolite correction is often required to define a true radiotracer input function in quantitative modeling of PET data. However, arterial puncture for blood sampling is often undesirable. To establish whether venous blood could substitute for arterial blood in metabolite analysis for quantitative PET studies ...

BACKGROUND AND OBJECTIVES: To determine the accuracy of fingerstick haemoglobin assessment in blood donors, the performance of a portable haemoglobinometer (HemoCue Hb 201+) was prospectively compared with that of an automated haematology analyzer (Cell-Dyn 4000). Haemoglobin values obtained by the latter were used as the 'true' result. MATERIAL AND METHODS: ...

BACKGROUND:: The immunosuppressive drug ciclosporin A has a narrow therapeutic window and a large inter- and intraindividual pharmacokinetic variability. Therapeutic drug monitoring of ciclosporin is usually performed in ethylenediaminetetraacetic acid blood, obtained by venous sampling. Dried blood spot sampling (DBS) could be a useful alternative sampling method, which also easily ...

Double lumen (DL) central venous catheters (CVC) often suffer from thrombosis, fibrin sheet formation, and/or suction towards the vessel wall, resulting in insufficient blood flow during hemodialysis. Reversing the catheter connection often restores blood flows, but will lead to higher recirculation. Single lumen (SL) CVCs have often fewer flow problems, ...

Hyperparathyroidism is common in the end-stage renal failure and may require surgical intervention. In addition, following multiple vascular access attempts central venous stenosis may occur. The results in high-volume venous blood flow through neck collaterals. Here, we describe a case of severe secondary hyperparathyroidism, high flow arteriovenous fistula and central ...

The i-STAT PCA can be used as a blood analyzer in critical avian patients, although single values must be interpreted carefully. The study of the acid-base status in companion birds is still in its infancy. Further research is needed to establish normal reference values in arterial blood gases, compare them ...

Objective-To evaluate effects of blood collection method and site on results of thromboelastography in healthy dogs. Animals-8 clinically normal purpose-bred dogs. Procedures-Blood was collected from the external jugular vein by syringe aspiration via direct venipuncture with a 20-gauge needle, through a central venous catheter, or into an evacuated tube with ...

Reconstruction of digital defects using the venous flap offer several advantages but remained unpopular owing to levels of venous congestion rates. We performed animal studies to test the hypothesis that an arterio-venous shunt increases pressure for peripheral flap perfusion and decreases venous congestion. Using an abdominal adipofascial flap model in ...

INTRODUCTION: The aim of this study was to investigate the contribution of the perioperative cell salvage process to the changes in erythrocyte 2,3-disphosphoglycerate (2,3-DPG) and glucose-6-phosphate dehydrogenase (G-6-PD) levels and phosphatidylserine (PS) expression using a self-control study comparing washed blood with venous blood. METHODS: Thirty patients undergoing elective heart and ...

PURPOSE: To evaluate the precision and accuracy of parallel-imaging compressed-sensing 4D phase contrast (PICS-4DPC) magnetic resonance imaging (MRI) venous flow quantification in children with patients referred for cardiac MRI at our children's hospital. MATERIALS AND METHODS: With Institutional Review Board (IRB) approval and Health Insurance Portability and Accountability Act (HIPAA) ...

OBJECTIVE: As inspired oxygen availability falls with ascent to altitude, some individuals develop high-altitude headache (HAH). We postulated that HAH results when hypoxia-associated increases in cerebral blood flow occur in the context of restricted venous drainage, and is worsened when cerebral compliance is reduced. We explored this hypothesis in 3 ...

Abstract Introduction: Glycemic control in critically ill patients has been the topic of an interesting debate during the last decade. An accurate continuous glucose monitoring system is essential to better understand this field. This prospective study thus evaluates the accuracy and technical feasibility of a continuous glucose monitoring system using ...

The Kidney Dialysis Outcomes Quality Initiative and Fistula First Initiative have embraced the arteriovenous fistula as the gold standard for hemodialysis accesses. Despite this status, fistulae are fraught with complex issues ranging from a high primary failure rate to high flow resulting in increased cardiovascular morbidity. It is important not ...

OBJECTIVES: To investigate the concordance of blood count indices measured locally and at a central laboratory. DESIGN AND METHODS: In a multi-center clinical trial of hydroxyurea therapy in infants with sickle cell anemia (BABY HUG), the concordance between blood count indices measured locally and at a central laboratory was investigated. ...

Techniques for measuring cerebral perfusion require accurate longitudinal relaxation (T1) of blood, an MRI parameter that is field dependent. T1 of arterial and venous human blood was measured at 7T using three different sources - pathology laboratory, blood bank and in vivo. The T1 of venous blood was measured from ...

BACKGROUND: Glucose oxidase biosensors are used in self-monitoring blood glucose concentrations. The capillary blood glucose quantitation requires a calibration curve. Due to the limitation in obtaining calibration curve from capillary blood, an alternate approach by using venous blood for neonatal measurement was investigated. METHODS: A signal correlation between oxygen saturated ...

BACKGROUND:: Transit time flow volume (TTFV) measurement, a non-Doppler-based ultrasound technology, has been shown to accurately evaluate the quality of coronary artery bypass grafts and improve outcomes of cardiac surgery. We hypothesized that TTFV measurements would also improve decision-making in microvascular free tissue transfer procedures. METHODS:: We measured TTFV in ...

Blood viscosity is an important determinant of microvascular hemodynamics and also reflects systemic inflammation. Viscosity of blood strongly depends on the shear rate and can be characterized by a two parameter power-law model. Other major determinants of blood viscosity are hematocrit, level of inflammatory proteins and temperature. In-vitro studies have ...

This study aimed to determine the minimum discard volume from central venous catheters (CVCs) to avoid dilution or contamination from flush or IV fluids. In 93 adult patients with CVCs, minimum discard volume findings were 9 ml for tunneled and 6 ml for nontunneled catheters. Nurses who obtain samples from ...

Objective: this study investigated the relationship between various parameters of venous blood gas analysis of gastric fundus veins and cervical esophagogastric anastomotic leaks after transhiatal esophagectomy. Background: decreased tissue perfusion is one of the causes of anastomotic leak. There are various methods used to assess gastric conduit perfusion, with different ...

BACKGROUND: Our aim in this study was to use ultrasonography of internal jugular vein (IJV) instead of visual estimation by eye and to get more precise estimation of central venous pressure at supine position for estimating blood loss in healthy volunteers. METHODS: The values of the sonographic IJV collapse index ...

Although many blood flow models have been constructed for cerebral arterial trees, few models have been reported for their venous counterparts. In this article we present a computational model for an anatomically accurate cerebral venous tree which was created from a CT angiography (CTA) image. The topology of the tree ...

BACKGROUND: Peripheral venous blood gas (pVBG) analysis in replacement of arterial blood gas (ABG) is limited by the unpredictable differences between arterial and venous values, especially for PCO(2) and pH (ΔPCO(2) and ΔpH). OBJECTIVES: We hypothesized that, using the theoretical relationship linking SvO(2) and blood flow, we could diminish the ...

OBJECTIVE: Quantitative cerebral blood flow (CBF) measured by single photon emission computed tomography (SPECT) with arterial blood sampling is one of the most reliable methods to assess the hemodynamics in individual patients. SPECT with venous blood sampling is less invasive. The present study compared the measurement of CBF using N-isopropyl-p-(iodine-123)-iodoamphetamine ...

Abstract Purpose: Ocular blood flow dysregulation has been implicated in the pathogenesis of glaucoma. Whereas the effect of single antiglaucoma substances on ocular blood flow has been addressed in various experiments, evidence for fixed combinations is sparse. In the present study, we set out to compare the effects of latanoprost ...

This study aimed to determine the influence of carotid artery surgery on ocular functions and ocular blood flow in patients with ocular ischaemic syndrome (OIS) in the late postoperative period. One hundred and eighty patients with OIS were operated on; 104 of them suffered from acute forms of the ischaemic ...

To determine whether retrobulbar blood flow (RBF) velocities are predictive of conversion to glaucoma. A total of 262 glaucoma suspects were prospectively selected. Participants had normal visual field, increased intraocular pressure, and glaucomatous optic disc appearance at baseline. Topographic analysis of the optic nerve head was performed using a confocal ...

To determine the relationship among visual field, neural structural, and blood flow measurements in glaucoma. Case-control study. Forty-seven eyes of 42 patients with perimetric glaucoma were age-matched with 27 normal eyes of 27 patients. All patients underwent Doppler Fourier-domain optical coherence tomography to measure retinal blood flow and standard glaucoma ...

The acid-base equilibrium is closely linked to gas exchange in the lungs, and respiratory exchange ratios are used to evaluate respiratory effectiveness and tissue oxygen levels. Acid-base indicators are determined in both arterial and venous blood samples. This study compares the usefulness of acid-base indicators of venous and arterial blood ...

Given the huge impact of vitamin D deficiency on a broad spectrum of diseases such as rickets, osteoporosis, mineral bone disease-vascular calcification syndrome, infectious diseases, but also several types of cancer and CNS diseases, reliable and simple methods to analyze the vitamin D status are urgently needed. We developed an ...

A microscale shear cell is used to study the formation of parabolic focal conic defects in the thermotropic smectic-A liquid crystal 8CB (4-octyl-4'-cyanobiphenyl). Defects are produced by four distinct methods: by the application of dilatational strain alone, by shear flow alone, by dilatational strain and subsequent shear flow, and by ...