Search Results
Results 451 - 500 of 1273
< 5 6 7 8 9 10 11 12 13 14 15 >
Kinnala P J - - 1999
OBJECTIVE: To investigate central haemodynamics in severe and mild acute pancreatitis in pigs. DESIGN: Randomised controlled experiment. SETTING: Animal laboratory, Finland. SUBJECTS: 24 domestic pigs weighing 21-27 kg. INTERVENTIONS: In 8 anaesthetised and mechanically ventilated pigs the pancreatic duct was cannulated and taurocholic acid was infused to induce severe acute ...
Moll W - - 1999
For a quantitative understanding of the venous Doppler sonograms, a model of the fetal cardiovascular system is proposed which stresses the significance of flow. The model comprises three major components: the heart which provides constant power and dynamic capacitance, the peripheral fetal and placental vascular beds with flow limiting conductances ...
Hosaka J - - 1999
RATIONALE AND OBJECTIVES: The authors performed this study to compare the in vivo efficacies of the temporary venous spring filter and the RF02 filter in an animal model. MATERIALS AND METHODS: Either the spring filter or the RF02 filter was placed in the inferior vena cava of 10 pigs each, ...
Bloomfield G - - 1999
BACKGROUND: To determine the ability of an externally applied continuous negative abdominal pressure device (CNAP) to reverse the effects of elevated intra-abdominal pressure on the central nervous and cardiovascular systems. METHODS: Anesthetized, ventilated swine had catheters placed for measurement of intra-abdominal (IAP), intracranial (ICP), central venous, pulmonary artery, pulmonary artery ...
Broekhuizen M L - - 1999
OBJECTIVE: To obtain insight into hemodynamics during abnormal cardiac development, a chick model was developed recently in which a spectrum of conotruncal anomalies, in combination with abnormal semilunar valves and/or pharyngeal arch artery malformations, was induced through extraembryonic venous obstruction (venous clip) at stage 17 (70-h incubation). METHODS: In chick ...
Poredos P - - 1999
The fibrinolytic system may play an important role in the development and progression of peripheral arterial occlusive disease. The fibrinolytic system of the whole blood and a diseased leg was investigated in twenty men with chronic peripheral atherosclerotic occlusive arterial disease (PAOD, clinical stage II according to Fontaine), aged from ...
Kongstad L - - 1999
BACKGROUND: Treatment of increased intracranial pressure often includes an active change in arterial and venous pressure, sometimes with draining of cerebrospinal fluid. We evaluated tissue and perfusion pressure during corresponding interventions in an organ enclosed in a rigid compartment with capillaries permeable for electrolytes and impaired autoregulation, conditions comparable to ...
Jeanneret C - - 1999
OBJECTIVES: the aim of this study was to provide normal values for venous diameter at rest, and venous diameter and physiologic venous reflux during a standardised Valsalva manoeuvre. The impact of the patient's sex, body mass index (BMI), and family history was investigated. MATERIAL AND METHODS: eighty legs of 40 ...
Malone M D - - 1999
Deep vein thrombosis (DVT) is a preventable cause of morbidity and mortality in patients who are hospitalized. An important part of the mechanism of DVT prophylaxis with intermittent pneumatic compression (IPC) is reduced venous stasis with increased velocity of venous return. The conventional methods of IPC use low pressure and ...
Kongstad L - - 1999
BACKGROUND: Dural puncture can be followed by postural headache and, in patients with cerebral infections, by brain stem herniation. The present study evaluates whether these complications may be related to the changes in hydrostatic pressure generated by the spinal fluid column when the dural sac surrounding the cerebrospinal tissue has ...
Kim D I - - 1999
To determine whether there is anatomical and/or functional impairment to venous return in patients with lymphedema, we examined venous dynamics in 41 patients with unilateral leg lymphedema. A Volometer was used for computer analysis of leg volume, a color Duplex Doppler scanner was used to determine deep vein patency and ...
Cesarone M R - - 1999
BACKGROUND: Edema is a common condition in most venous and lymphatic diseases. The ACI edema testers (ET) have been developed to objectively evaluate the presence of edema. Two types of testers have been developed. ET1 is a soft plastic plate (5 x 2 cm) characterised by two parallel protrusions while ...
Wang S Y - - 1999
The distributions of nitroprusside (NP) induced changes in vascular capacitance, arterial versus venous, are unknown. We measured canine ileal arterial and venous pressures and total (isolated loop) vascular volumes (scintigraphy), before and during NP infusion. NP sufficient to decrease perfusion pressure by 30% increased total vascular volume to 111 +/- ...
Wells J K - - 1999
The superficial femoral-popliteal vein (SFPV) is a reliable conduit for aortoiliac, infrainguinal, and venous reconstructions. In this prospective study, we characterized the anatomic and physiologic changes in SFPV harvest limbs and their relationship to the development of late venous complications. Since 1990, we have studied 61 patients after harvest of ...
Crandall C G - - 1999
Whole body heating in humans increases skin blood flow (SkBF) and decreases central venous pressure (CVP). This study sought to identify whether elevations in SkBF are augmented during passive heating if CVP is increased during the heat stress. Seven subjects were exposed to passive heating. Once SkBF was substantially elevated, ...
Hahn T L - - 1999
BACKGROUND: The pathophysiologic mechanism for tissue damage in chronic venous insufficiency (CVI) is venous hypertension (VH), the primary mediator behind leukocyte trapping in tissues. We developed a new rodent model of chronic hindlimb VH to allow testing of the microvascular dysfunction that occurs in clinical CVI. MATERIALS AND METHODS: Hindlimb ...
Pitto R P - - 1999
The aim of this study was to assess the relevance of drainage placed along the linea aspera for the prevention of fat embolism and cardiopulmonary impairment during the insertion of a cemented stem. We studied 40 patients with coxarthrosis randomly allocated to total hip arthroplasty with proximal drainage or without ...
Ravenscroft E F - - 1999
A program evaluation of hemodialysis vascular access monitoring was undertaken to determine the effectiveness of serial, objective measurement, running venous dialysis pressures, in reducing access thrombosis in arterio-venous fistulae, as well as to assess the feasibility of long-term, routine monitoring for clients in a limited-care community hemodialysis unit. In all, ...
Takase S - - 1999
One of the hallmarks of venous insufficiency is an elevated venous pressure. While a number of mechanisms have been proposed for vascular and parenchymal cell damage following venous pressure elevation, such as white cell infiltration, a key question remains as to what degree venous occlusion and flow interruption per se ...
Wertheim D - - 1999
Compression therapy is the principal treatment for leg ulcers associated with venous disease. The efficacy of compression therapy can be variable, which may in part be owing to the degree of compression applied. However, if the mechanism of action of this treatment could be better understood, it might be possible ...
Cheatham M L - - 1999
BACKGROUND: Intra-abdominal hypertension and abdominal compartment syndrome cause significant morbidity and mortality in surgical and trauma patients. Maintenance of intravascular preload and use of open abdomen techniques are essential. The accuracy of pulmonary artery occlusion pressure (PAOP) and central venous pressure (CVP) in patients with intra-abdominal hypertension has been questioned. ...
Headley J M - - 1998
Critical care practice has greatly changed over the last three decades. This is partly due to the advent of the pulmonary artery catheter and subsequent advances in technologies associated with it. The key determinants of cardiac performance, pressure, flow, and volume, are assessed either directly or indirectly. Parameters that were ...
Emeljanov S I - - 1998
BACKGROUND: This study was initiated to find a method of determining the prognosis for possible changes in hemodynamic and respiratory parameters in patients with pneumoperitoneum (PP). METHODS: We devised a model for a pseudopneumoperitoneum (PPP), which is created by encircling the wide pneumochamber on the entire abdomen and inflating it ...
Magder S - - 1998
To determine whether the venous circuit constitutively produces nitric oxide (NO), we infused the NO synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME) into anesthetized and mechanically ventilated pigs and measured venous circuit parameters. We measured cardiac output (Q) by thermodilution and obtained arterial (Part), central venous pressure (in the inferior vena ...
Olsen H - - 1998
Venous compliance in the calf of humans and its importance for capacitance function in relation to age were studied with the aid of 22, 44, and 59 mmHg lower body negative pressure (LBNP). Negative pressure transmission to the calf as well as changes in calf volume were studied, and venous ...
McMahon C G - - 1998
The results of different vascular tests used in the diagnosis of cavernosal arterial insufficiency and cavernosal venous leakage were compared in 168 men, with an average age of 62.9 y to determine which were the most reliable. One hundred and forty-five men had penile arterial insufficiency demonstrated with digital subtraction ...
Kresh J Y - - 1998
The dynamic coupling between cardiac pump performance and vascular arterial-venous capacitive and resistive properties was examined analytically and experimentally to determine the feasibility of maintaining systemic and pulmonary circulation, devoid of the right heart. Analysis of the cardiovascular system (excluding neurohumoral factors), used a mathematical representation of the major determinants ...
Malanin K - - 1998
The venoarteriolar response (VAR) of the skin in legs caused by experimental venous hypertension was measured using a new, double-wavelength laser Doppler probe technique (543 nm and 780 nm). This enables the measurement of the laser Doppler flux in the superficial and deep layers of the skin simultaneously. The recordings ...
Kirollos M M - - 1998
PURPOSE: A technique to control venous bleeding after retropubic prostatectomy is described. MATERIALS AND METHODS: A man underwent retropubic prostatectomy for an enlarged benign prostate following which hemorrhage occurred. RESULTS: After failure of other more traditional methods of hemostasis, the bleeding was stopped by direct anterior digital rectal pressure. CONCLUSIONS: ...
Lambermont B - - 1998
The aim of the present study was to determine effects of positive end expiratory pressure (PEEP) application on peripheral venous capacitance and relate them to concomitant central hemodynamic disturbances. The venous volume-pressure (V/P) relationships were studied in 6 intact anesthetized pigs to describe the effects of PEEP on systemic venous ...
Ludwig L M - - 1998
In Part I of this two-part series on cardiovascular assessment, the author described basic components of physical assessment relating to cardiac assessment such as skin color, integrity and hydration, pulses, shortness of breath, edema, and weight changes. In Part II, the intricacies of accurate blood pressure measurement, central venous pressure ...
Alzeer A - - 1998
PURPOSE: To determine whether central venous pressure at the common iliac vein reflects right atrial pressure in adult patients. METHODS: In this prospective, non-blinded study 26 mechanically-ventilated adult patients were studied. Simultaneous pressure readings were obtained from the right atrium (TCVP) and the common iliac vein (ACVP). RESULTS: There was ...
Xu F - - 1998
Acute head-down tilt (AHDT, -30 degrees) in humans induces a transient ventilatory augmentation for 1-2 min accompanied by a high venous return. However, the mechanisms underlying this respiratory response remain obscure because of limitations of experiments carried out in human subjects. The present study was undertaken to determine whether AHDT-induced ...
Semeniuk L M - - 1998
BACKGROUND: Toborinone (OPC-18790), a phosphodiesterase III inhibitor, enhances cardiac contractility and is an arterial dilator. However, its effects on the venous system have not yet been clearly defined. Because toborinone administration reduces left ventricular (LV) end-diastolic pressure, it is probably also a venodilator. Because of the known arterial effects and ...
Styf J - - 1998
BACKGROUND: Abnormally increased pressure in the anterior compartment of 20 legs in 10 subjects was induced by applying venous stasis of a casted leg and external compression by a cylindrical air splint of the contralateral leg. The effects of increased intramuscular pressure (IMP) on blood perfusion pressure and clinical symptoms ...
McGee S R - - 1998
OBJECTIVE: To explain why investigations of the measurement of central venous pressure (CVP) usually reveal a discrepancy between the clinician's estimate of CVP from physical diagnosis and supine measurement with a catheter. Data from MEDLINE search, personal files, and bibliographies of textbooks on physical diagnosis and cardiology were used. RESULTS: ...
Tran C C - - 1998
The purpose of the present work was to study in vivo in rat the consequences of repeated exposures to sustained +Gz centrifugations on the venous pressure and on the venous tone, that one evaluated by measuring the equilibrium pressure of all vessels in the circulation when the flow is null ...
Wiger P - - 1998
OBJECTIVES: To study the effects of limb elevation on abnormally increased intramuscular pressure (IMP) and blood perfusion pressure in the anterior compartment of the leg. DESIGN: An experimental cross-over design. The test leg was elevated and the control leg was kept at heart level. PARTICIPANTS: Eight healthy subjects with a ...
Stotz-Potter E - - 1998
The mediodorsal nucleus of the thalamus (MD) has connections with central autonomic centers involved in cardiovascular control and undergoes severe degeneration in fatal familial insomnia, a human disease characterized by progressive dysautonomia. Microinjections of the GABAA antagonist bicuculline methiodide (BMI) into the medial and central portion of the MD lead ...
Klein A L - - 1998
Aging influences pulmonary venous flow and mitral inflow velocities. The duration of pulmonary venous atrial reversal flow exceeds that of the mitral inflow A wave in patients with left ventricular end-diastolic pressures greater than 15 mm Hg. The objective of this study was to investigate the effect of age on ...
Robert Y C - - 1998
STUDY OBJECTIVE. To determine the effect of different positional degrees on hemodynamics, especially central venous pressure and intraocular pressure, and a possible interrelationship, during laparoscopic surgery. SETTING. University teaching hospital (Canadian Task Force classification II-1). PATIENTS: Seven women undergoing elective gynecologic laparoscopy. INTERVENTIONS: The women were monitored for heart rate, ...
Bicchi M - - 1998
Felodipine is a second-generation dihydropyridine calcium antagonist used to treat mild to moderate arterial hypertension. The authors used venous occlusion plethysmography to study the effect of this drug on lower limb arterial inflow and venous outflow in 10 at rest patients with mild essential hypertension. They also sought correlations between ...
Edouard D A - - 1998
To assess the contribution of the arterial and venous systems in the hemodynamic changes of normal pregnancy, we studied blood flow, vascular resistance, venous tone, and the viscoelastic properties ("creep") of the upper and lower limbs (using plethysmography), aortic distensibility (using pulse wave velocity measurements), and cardiac dimensions (using echocardiography) ...
Dabrowiecki S - - 1998
To study the influence of venous hypertension, which develops in lower limbs under pneumoperitoneal pressure, on microcirculation, plethysmographic measurements were performed in patients before and during laparoscopic and traditional (open) cholecystectomy. During laparoscopy, isovolumetric venous pressure (estimate of capillary pressure), and filtration coefficient (estimate of patent capillary surface) decreased, which ...
Zhang Y - - 1998
The significance of the sympathetic nervous system (SNS) in regulating peripheral vascular resistance and cardiac function in fish has been well established, whereas its effect on venous function in vivo is unknown. Two protocols were employed in the present study to evaluate SNS effects on the venous system in intact, ...
Fukuoka M - - 1998
Foot venous pressure measurement is considered to be useful for assessing lower limb venous insufficiency, because venous hypertension is the main factor predisposing to venous insufficiency. In this study, we investigated the utility of foot venous pressure measurement in the evaluation of venous insufficiency. A total of 148 limbs of ...
Becker K K - - 1998
Complications associated with pulmonary artery catheters (PACs) include interpretation errors, insertion problems, sepsis, thrombosis, and dysrhythmias. Alternatives to the use of PACs include the central venous pressure catheter, measurement of cardiac output by thoracic electrical bioimpedance, gastric tonometry and the measurement of serum lactate level, and the still to be ...
Thorne S A - - 1998
AIMS: Protein losing enteropathy is a serious complication of Fontan surgery. The aim of this study was to investigate gastro-intestinal protein loss in adults with congenital heart disease, both with and without Fontan surgery, and to correlate findings with systemic venous pressure. METHODS AND RESULTS: Forty eight patients were studied. ...
Rostrup M - - 1998
Arterial and venous plasma catecholamine responses to 15 min of cycling at 60% of maximal oxygen uptake were examined 11 times during exercise and recovery in nine young men. Intra-arterial blood pressure, heart rate and oxygen uptake were recorded continuously. All variables increased significantly during the initial 4 min, after ...
Gamble J - - 1998
1. We studied human lower limbs to test the hypothesis that the application of small cumulative venous congestion pressure steps is associated with a reduction in precapillary resistance. 2. Strain gauge plethysmography was performed on twenty-one young subjects (22.7 +/- 0.6 years). At each of the small cumulative pressure steps, ...
< 5 6 7 8 9 10 11 12 13 14 15 >