Search Results
Results 201 - 250 of 1271
< 1 2 3 4 5 6 7 8 9 10 >
Kolbach D N - - 2005
BACKGROUND: Accepted diagnostic criteria exist for the diagnosis of deep vein thrombosis (DVT). However, no uniform definition for the diagnosis and treatment of the post-thrombotic syndrome (PTS) exists. We examined the various definitions of PTS that are used and their relationships with invasive venous pressure measurement. METHODS: Patients who had ...
Skals Marianne - - 2005
The effects of adrenergic stimulation on mean circulatory filling pressure (MCFP), central venous pressure (P(CV)) and stroke volume (Vs), as well as the effects of altered MCFP through changes of blood volume were investigated in rattlesnakes (Crotalus durissus). MCFP is an estimate of the upstream pressure driving blood towards the ...
Ho A M-H - - 2005
Continuous central pressure monitoring and simultaneous continuous infusion via the same central venous catheter are sometimes necessary. Based on theoretical calculations and experimental measurements, we have determined that pressure monitoring is essentially unaffected if the continuous infusion rate is 50 ml.h(-1) or less for an adult and a paediatric central ...
Dix F P - - 2005
Patients with chronic venous insufficiency often have combined superficial and deep venous incompetence. The aims of this study were to determine the effects of superficial venous surgery (SVS) on deep venous haemodynamics and on ambulatory venous pressure (AVP) and to determine if the AVP tourniquet test can predict the effect ...
Bergan John J - - 2005
Chronic venous insufficiency is linked to venous hypertension and forces of shear stress on the endothelium. Venous hypertension depends upon two forces: the weight of a column of blood from the right atrium transmitted through the valveless vena cava and iliac veins to the femoral vein, and pressure generated by ...
Pascarella Luigi - - 2005
Recent histologic and immunocytochemical evidence of venous leg ulcers supports the hypothesis that lesions observed at different stages of chronic venous insufficiency may be associated with, and possibly caused by, an inflammatory process. Evidence has been obtained that venous valve deficiency may be associated with leukocyte infiltration into valve leaflets; ...
Krantz T - - 2005
BACKGROUND: Hypovolaemia may be considered to represent a volume-restricted cardiac output (CO), but CO varies inversely with the haemoglobin concentration (Hb) and a maximal mixed venous oxygen saturation (SvO2) may be a better target for volume administration than a maximal CO. METHODS: In 10 anaesthetized pigs, volume loading with 6% ...
Munns Suzanne L - - 2005
The effects of treadmill exercise on components of the cardiovascular (heart rate, mean arterial blood pressure, central venous pressure, venous return) and respiratory (minute ventilation, tidal volume, breathing frequency, rate of oxygen consumption, rate of carbon dioxide production) systems and on intra-abdominal pressure were measured in the American alligator, Alligator ...
Anderson Stephen I - - 2005
The decrease in pre-capillary resistance in the human calf during gradual cumulative increases in venous congestion pressure has been proposed to represent vasodilator signalling between the venous and arterial microcirculations. The present study investigated whether prostaglandins are involved in this local flow regulation by measuring calf blood flow and microvascular ...
Wang Jiun-Jr - - 2006
Compared with arterial hemodynamics, there has been relatively little study of venous hemodynamics. We propose that the venous system behaves just like the arterial system: waves propagate on a time-varying reservoir, the windkessel, which functions as the reverse of the arterial windkessel. During later diastole, pressure increases exponentially to approach ...
Danielsson G - - 2005
PURPOSE: To define the association between venous volume as measured with air-plethysmography and the duplex ultrasound measured diameter of incompetent perforator of the lower limb. PATIENTS AND METHODS: Thirty-six patients with chronic venous disease were investigated with air-plethysmography and duplex ultrasound. Venous volume and venous filling time was measured. Venous ...
Sahin Altan - - 2005
STUDY OBJECTIVE: Previous studies suggest a correlation of central venous pressure (CVP) with peripheral venous pressure (PVP) in different clinical setups. The aim of this study was to investigate the effect of measurement site on PVP and its agreement with CVP in patients undergoing general anesthesia. DESIGN: Prospective randomized study. ...
Létienne Robert - - 2005
The aim of the present study was to determine whether donitriptan and sumatriptan decreased jugular venous oxygen saturation and increased carbon dioxide partial pressure in venous blood. However, previous studies conducted with these compounds cannot discriminate whether the decrease of venous oxygen saturation is dependent of cranial vasoconstrictor. In the ...
Molnár Andrea Agnes - - 2006
INTRODUCTION: In situ biomechanical properties of peripheral large veins were compared between asymptomatic young patients who had previously unilateral femoro-popliteal deep venous thrombosis (DVT) and age-matched, healthy controls; the aim of this study was to assess local or generalized alterations of venous wall biomechanics in postthrombotic patients. PATIENTS AND METHODS: ...
Okazaki Kazunobu - - 2005
We dissected the relative contribution of arteriovenous hemodynamics, the venoarteriolar response (VAR), and the myogenic reflex toward a decrease in local blood flow induced by venous congestion. Skin blood flow (SkBF) was measured in 12 supine subjects via laser-Doppler flowmetry 1) over areas of forearm and calf skin, in which ...
Van Tricht Ilse - - 2005
The hemodynamics in the vascular access graft are influenced by the flow aspirated and injected through the two needles during hemodialysis. For the first time, the impact of needle flow on vascular access performance, measured in an in vitro set up, is reported. A vascular access model, consisting of a ...
Singh D V - - 2005
The intravenous (i.v.) infusion of lipopolysaccharide (LPS) of E. coli endotoxin in buffalo calves (n = 15) at 5 microg/kg bw per h for 3 h caused a significant (p<0.05) fall in plasma volume, blood volume, haematocrit haemoglobin, and systolic, diastolic and pulse pressure, mean arterial pressure and central venous ...
Cox Paul - - 2005
OBJECTIVES: The measurement of central venous pressure (CVP) is used to assess intravascular status. Although this is usually accomplished by placement of a central venous catheter (CVC), there are circumstances when placement of a CVC may be technically difficult or impossible. The current study investigates the feasibility of measuring CVP ...
Patel Rupa - - 2005
We describe the case of a 76-year-old man with a renal cell carcinoma thrombus extending into the right atrium, prolapsing across the tricuspid valve into the right ventricle during diastole, and producing sufficient portal venous pressure to result in intestinal venous thrombosis and necrosis of the upper gastrointestinal mucosa. The ...
Magder Sheldon - - 2005
PURPOSE OF REVIEW: Central venous pressure is a very common clinical measurement, but it is frequently misunderstood and misused. As with all hemodynamic measurements, it is important to understand its basic principles. RECENT FINDINGS: This analysis indicates that it is best to always consider the significance of central venous pressure ...
Kim Kyongsong - - 2005
BACKGROUND: Measurement of dural sinus or drainage vein pressure is useful for determining the appropriate treatment for some patients. We report a novel measurement procedure that reduces bleeding from the needle puncture site as well as further tearing of the wall. METHODS: The vessel is punctured through the patch by ...
Alemohammad Mahmood - - 2005
Although central venous pressure (CVP) is a valuable guide and measurement during cardiac surgery anesthesia, there are many occasions however, when the time consumed in inserting a peripheral catheter, defeats the actual purpose. The purpose of this study was to compare central venous pressure and internal jugular veins pressure, and ...
Korkut A Kubilay - - 2005
The early patency of arteriovenous fistulas created for hemodialysis is affected by various factors, including venous stenosis. We conducted a study to investigate the effect of venous stenosis on early patency by examining perioperative arterial and venous pressures of the fistula. Among the 15 patients selected for the study, 11 ...
Sandblom Erik - - 2005
Cardiac preload (central venous pressure, P(CV), mean circulatory filling pressure (MCFP), dorsal aortic blood pressure (P(DA)) and relative cardiac output (Q) were measured in sea bass (Dicentrarchus labrax) at rest and while swimming at 1 and 2 BL s(-1). MCFP, an index of venous capacitance and the upstream venous pressure ...
Sahin Altan - - 2005
Previous studies suggest a correlation of central venous pressure (CVP) with peripheral venous pressure (PVP) in different clinical settings. The effect of body temperature on PVP and its agreement with CVP in patients under general anesthesia are investigated in this study. Fifteen American Society of Anesthesiologists I-II patients undergoing elective ...
Pilcher D V - - 2005
BACKGROUND: Poor oxygenation might occur in transplanted lungs as a result of reperfusion injury and lack of lymphatic drainage. Low central venous and pulmonary capillary wedge pressures are advocated to reduce pulmonary edema and maximize oxygenation but might adversely affect cardiac index, circulation, and renal function. METHODS: Histories, intensive care ...
Martin Elizabeth A - - 2005
We tested whether central venous pressure (CVP) changes during vasoactive drug injections used for baroreflex assessment in humans. We measured CVP during sequential intravenous boluses of nitroprusside (NTP) and phenylephrine (PHE; modified Oxford technique). NTP caused a decrease in CVP of 1.9+/-0.2 mmHg from baseline (P<0.01) and PHE caused an ...
Dhawan Vivek - - 2005
In humans, multiparity (repeated pregnancy) is associated with increased risk of cardiovascular disease. In rats, multiparity increases the pressor response to phenylephrine and to acute stress, due in part to changes in tone of the splanchnic arterial vasculature. Given that the venous system also changes during pregnancy, we studied the ...
Lin Ming-Chih - - 2005
PURPOSE: To compare the right atrial pressure to the central venous pressures measured at different points in spontaneously breathing children and try to find a formula to estimate right atrial pressure by central venous pressure measurement. METHODS: Fifty-one children, aged 5 +/- 4.7 years, who underwent right heart catheterization were ...
Sandblom E - - 2005
The baroreflex was triggered by altering branchial blood pressure with pre- and post-branchial occlusions for 30 s in rainbow trout Oncorhynchus mykiss. The cardiac limb of the baroreflex was monitored by continuous heart rate (f(H)) measurements. Responses of venous capacitance vessels were assessed, immediately following either occlusion, by measuring mean ...
Fullana J M - - 2005
To present a virtual model, the venous return simulator (VRS), designed to compute venous hemodynamic variations when compression is applied to the leg. The VRS defines a numerical network of the lower extremity and computes the dynamic variables (flow rate, venous diameter and internal pressure) for a defined external pressure. ...
Baumann Ulrich A - - 2005
INTRODUCTION: Increasing blood volume and cardiac output is one of the most commonly needed intervention in the primary care of traumatized and severely ill patients. Although cardiac filling pressures have severe limitations in assessing the preload, central venous pressure (CVP) is the invasive measure most frequently used in clinical practice ...
Moore-Olufemi Stacey D - - 2005
BACKGROUND: Mesenteric venous hypertension and subsequent gut edema play a pivotal role in the development of intra-abdominal hypertension. Although gut edema is one cause of intra-abdominal hypertension, its impact on gut function is unknown. The purpose of this study was to create a model of acute hydrostatic gut edema and ...
Pascarella Luigi - - 2005
Clinical observation suggests that chronic venous insufficiency is related to failure of venous valves. Duplex ultrasound studies of lower extremity superficial veins regularly show valve failure and venous reflux. Gross morphologic observation of venous valves in surgical specimens shows tearing, splitting, scarring, and disappearance of valves. Venous valve damage is ...
de Groot Patricia C E - - 2005
Classical venous occlusion plethysmography (VOP) of the leg, often used to assess venous compliance, measures properties of the whole calf, including volume changes at the arterial side and the interstitial fluid accumulation that occurs as a result of the enhanced capillary pressure during venous occlusion. We present an ultrasound technique ...
Rizvi K - - 2005
BACKGROUND: Previous investigations have identified significant interobserver variability in the measurements of central venous pressure and pulmonary artery occlusion pressure in critically ill patients. Large interobserver variability in the measurement of vascular pressures could potentially lead to inappropriate treatment decisions. OBJECTIVE: We postulated that adding an airway pressure signal (Paw) ...
Upton Richard N - - 2005
There have been few reports of pharmacokinetic models that have been linked to models of the cardiovascular system. Such models could predict the cardiovascular effects of a drug under a variety of circumstances. Limiting factors may be the lack of a suitably simple cardiovascular model, the difficulty in managing extensive ...
Katsenis Konstantinos - - 2005
Initially, the progression of chronic venous insufficiency is related to venous hypertension. The earliest complaints or symptoms, as well as vessel wall deterioration, valve restructuring, and, eventually, varicose veins, result not only from elevation of pressure, but also from a cascade of biochemical events related to both the macro- and ...
Powner David J - - 2005
The objective of the study was to compare measurements of central venous pressure (CVP) and pulmonary artery occlusion pressures (PAoP) as estimates of intravascular volume during the first 96 hours of fluid therapy after traumatic brain injury (TBI). One thousand five hundred ten simultaneous CVP and PAoP measurements from 31 ...
Oohashi Satomi - - 2005
PURPOSE: We investigated whether central venous pressure (CVP) or pulmonary capillary wedge pressure (PCWP) can accurately reflect the status of circulating blood volume (CBV) during the perioperative period in adult patients after extended transthoracic esophagectomy. METHODS: In 16 adult patients undergoing esophagectomy, simultaneous measurements of CVP, PCWP, and CBV were ...
Wilson Timothy D - - 2005
Adrenergic nerves innervate the human cerebrovasculature, yet the functional role of neurogenic influences on cerebral hemodynamics remains speculative. In the current study, regional cerebrovascular responses to sympathoexcitatory reflexes were evaluated. In eight volunteers, contrast-enhanced computed tomography was performed at baseline, -40 mmHg lower body negative pressure (LBNP), and a cold ...
O'Mara Michael S - - 2004
Standard therapy for abdominal compartment syndrome is laparotomy. In many patients, laparotomy involves a recent incision; for others, volume of resuscitation may be the cause. The components separation technique allows difficult abdominal closure. The authors studied the effect of a modified separation of parts on abdominal compartment syndrome in an ...
Jones Philip M - - 2004
We report a venous oxygen embolism that occurred in a 66-yr-old man after 60 mL of 3% hydrogen peroxide was injected into a perianal fistula intraoperatively to locate its internal opening. The diagnosis was made after detecting hypoxemia, decreased end-tidal carbon dioxide tension, systemic hypotension, increased central venous pressure, and ...
Sanelli Pina C - - 2004
OBJECTIVE: Our aim was to determine the safety and feasibility of using a central venous catheter for rapid contrast injections during CT. MATERIALS AND METHODS: An in vitro experiment was performed using a 7-French Arrow-Howes multilumen central venous catheter. Each catheter port was tested by varying contrast agent flow rates ...
Munns Suzanne L - - 2004
The effects of treadmill exercise on components of the cardiovascular (venous return, heart rate, arterial blood pressure) and respiratory systems (minute ventilation, tidal volume, breathing frequency, oxygen consumption, carbon dioxide production) and intra-abdominal pressure were investigated in the Savannah monitor lizard, Varanus exanthematicus B., at 35 degrees C. Compared with ...
Rhodes Andrew - - 2004
OBJECTIVE: In 2003, critical care and infectious disease experts representing 11 international organizations developed management guidelines for early goal-directed therapy that would be of practical use for the bedside clinician, under the auspices of the Surviving Sepsis Campaign, an international effort to increase awareness and improve outcome in severe sepsis. ...
Takase S - - 2004
OBJECTIVES: To identify possible mechanisms for destruction of valves in chronic venous hypertension and the results of treatment with an anti-inflammatory micronized purified flavonoid fraction. MATERIAL AND METHODS: The saphenous vein valves in a rat model of venous hypertension caused by a femoral arterial-venous fistula were studied. Studies included femoral ...
Tabrizchi Reza - - 2004
Some analogues of arginine vasopressin (AVP) reportedly possess hypotensive properties, and two such peptides are Cys(1)-Tyr(2)-Phe(3)-Val(4)-Asn(5)-Cys(6)-Pro(7)- d-Arg(8)-Gly(9)-NH(2) (VD-AVP) and d(CH(2))(5)-Cys(1)- d-Tyr(Et)(2)-Arg(3)-Val(4)-Asn(5)-Cys(6)-Lys(7)-Lys(8)-ethylenediamine(9) (TA-LVP). In the present investigation we examined the effects of TA-LVP (0.3, 1.0 and 3.0 microg/kg/min), VD-AVP (0.3, 1.0 and 3.0 microg/kg/min) and AVP (1.0, 3.0, 10 ng/kg/min) on ...
Valenza Franco - - 2005
OBJECTIVE: To investigate whether negative extra-abdominal pressure (NEXAP) improves respiratory function and induces a blood shift from the intrathoracic compartment and to assess whether these effects are influenced by abdominal pressure. DESIGN AND SETTING: Prospective, randomized, controlled trial in the animal laboratory of a university hospital. SUBJECTS: Eight sedated and ...
Weingarten Toby N - - 2004
Venous pressures measured from peripheral venous catheters (PVP) closely estimate the central venous pressure (CVP) in surgical and critically ill patients. CVP is often used to estimate intravascular volume; however, fluctuations of CVP may also be induced by changes in venous tone caused by alpha-adrenergic catecholamine stimulation. We simultaneously monitored ...
< 1 2 3 4 5 6 7 8 9 10 >