The elevated ambulatory pressure in the peripheral venous system of chronic venous insufficiency (CVI) patients manifests itself not only in the form of disturbed macrocirculation but also and particularly in microangiopathic changes. For this reason, it is closely correlated with trophic disorders of the skin and can ultimately lead to ...

BACKGROUND: The present study was designed to determine whether there is a physiological explanation for the predisposition of patients with certain angiographic characteristics to haemorrhage from cerebral arteriovenous malformations (AVMs). METHODS: Intra-operative measurement of feeding artery pressure (FAP) and intravascular pressures in the draining venous system [draining vein pressure (DVP) ...

External jugulars are not reliable as an indication of right atrial pressure because of their passage through two right angles and also because they are often not visible. The top level of internal jugular pulsations which are transmitted to the skin of the neck serves as a pulsation manometer. A ...

Convective transport across the dialysis membrane has long been known to be a good alternative to diffusion. Among the advantages of haemofiltration over conventional haemodialysis is a better cardiovascular stability. Haemofiltration has a more physiological response to fluid removal than haemodialysis: (i) blood volume may be better preserved, especially in ...

This study investigates whether the pressure parameters obtained from the Swan-Ganz catheter (SGC) accurately reflect the circulating blood volume just after en bloc resection of the thoracic esophagus with regional lymph node dissection. It is well known that this operation induces severe hemodynamic changes and although the pressure parameters obtained ...

One of the hallmarks of chronic venous insufficiency (CVI) is an elevated venous pressure. However, no direct link at the cellular and molecular levels between venous hypertension and actual tissue damage in CVI has been established. Evidence for generations of an inflammatory reaction and several molecular alterations in the development ...

OBJECTIVE: To assess the relationship between central venous pressure values and bioelectrical impedance vector analysis (BIVA), which may be used as complementary methods in the bedside monitoring of fluid status. DESIGN: Cross-sectional evaluation of a consecutive sample. SETTING: Intensive care unit of a university hospital. PATIENTS: One hundred and twenty-one ...

Cardiac output is largely controlled by venous return, the driving force of which is the energy remaining at the postcapillary venous site. This force is influenced by forces acting close to the right atrium, and internally or externally upon the veins along their course. Analogue models of the venous system ...

In view of the resemblance of exercise-induced plethysmographic changes with those obtained by direct venous pressure measurement, we decided to use a combination of photoplethysmography (PPG) and hydrostatic pressure calibration to determine the PPG/pressure relationship. A standard foot dorsiflexion exercise involving stepwise position changing was performed which induced hydrostatic pressure ...

Dural puncture with corticosteroid could be a predisposing factor for cerebral venous thrombosis (CVT). A 35-year-old woman using oral contraception was treated with corticosteroid epidural infiltration for L5 radiculalgia. The following day a postural headache developed and accidental dural puncture was suspected. Four days later, she presented with fever and ...

Up until recently the evaluation of CVR (analysis of pulsatility) had been a priority in Doppler sonography. In preterm and term infants with open fontanels and sutures this information is restricted despite its value in extreme situations. Continuous Doppler sonography allows a new approach to monitoring pathophysiologic processes. In connection ...

The purpose of this study was to obtain objective information on the necessity of invasive anesthetic monitoring during radical prostatectomy. We reviewed retrospectively the charts of 257 patients undergoing radical prostatectomy on an established pathway which did not include the intraoperative use of an arterial line or central venous catheter. ...

PURPOSE: We evaluated the effects of wearing 20 to 30 mm Hg gradient thigh-length stockings during daily activity on the lower leg venous system. METHODS: Twenty-one healthy women volunteers, aged 39 +/- 12 years, were examined. One subject was clinical class 4, one was class 2, two were class 1, ...

The application of laparoscopic technique has gained popularity in the past decade. Numerous studies have qualified and quantified the systemic impact of acutely elevated intra-abdominal pressure during pneumoperitoneum at time of laparoscopy. The major hemodynamic effects are increased central venous pressure, increased systemic vascular resistance and systemic hypertension. Reductions in ...

Swelling, or increased volume, secondary to venous congestion is thought to be a factor in some upper limb conditions. This study aimed to establish a safe, easily applied method of inducing a transitory increase in forearm and hand volume that could be used as a symptom provocation test for upper ...

We conducted a series of studies to develop and test a rapid, noninvasive method to measure limb venous compliance in humans. First, we measured forearm volume (mercury-in-Silastic strain gauges) and antecubital intravenous pressure during inflation of a venous collecting cuff around the upper arm. Intravenous pressure fit the regression line, ...

Blood return into the cardiotomy reservoir is usually reduced when a cardiopulmonary bypass (CPB) is initiated through a peripheral access, even if the tip of the venous cannula is pushed into the right atrium. A centrifugal pump can be placed on the venous line to increase the negative pressure. Surgery ...

We evaluated the hypothesis that venous congestion (increased venous volume), as reflected by venous hypertension (increased venous pressure), can arise when the right ventricle is unable to elevate the pulmonary arterial pressure sufficiently to propel the cardiac output through an anatomically inadequate or inappropriately constricted pulmonary vasculature. Changes in venous ...

BACKGROUND: Deep venous refluxes play an important triggering role for the development of venous leg ulcers. Compression therapy is able to reduce these refluxes depending on pressure and the kind of material being used. OBJECTIVE: To compare the efficacy of compression bandages of varying pressure and material (elastic, long-stretch versus ...

OBJECTIVE: Minimally invasive open heart surgery involves limited intrathoracic cannulation sites necessitating cardiopulmonary bypass to be initiated via peripheral access using percutaneous cannulae with the tip placed into the right atrial cavity. However, surgery involving the opening of the right heart obliges the surgeon to maintain the end of the ...

BACKGROUND: Medical-grade compression of class I (20-30 mmHg) and class II (30-40 mmHg) have been shown to be beneficial against venous hypertension or congestion. Relatively few studies address the effects of ready-to-wear (RTW) lightweight gradient compression pantyhose on venous symptoms. OBJECTIVE: To perform a study comparing the effects of two ...

BACKGROUND: This study addresses the question of whether the elevation of the mean arterial pressure and central venous pressure in response to pneumoperitoneum for laparoscopic surgery is caused by increases in central blood volume and/or cardiac output. METHODS: Eleven patients in good cardiopulmonary health and scheduled for laparoscopic cholecystectomy, with ...

INTRODUCTION: As the mean age of haemodialysis patients is increasing, fewer patients will have suitable blood vessels for the creation of a Brescia-Cimino fistula and an increased use of graft implants is to be expected. METHODS: To assess the change in vascular access and the use of surveillance techniques, all ...

BACKGROUND: Measurement of foot venous pressure (FVP) is useful for evaluating chronic venous insufficiency (CVI) functionally, because CVI always causes venous hypertension. In the present study, the various FVP parameters were analysed according to the new classification of venous disorders based on clinical, aetiological, anatomical and pathophysiological data (the CEAP ...

Monitoring the patency of hemodialysis interposition grafts is recommended to improve graft survival. Which blood flows best predict graft survival is not known. We monitored venous pressures in 32 dialysis patients over a median of 252 days at variable flow rates of the blood pump (Qb). Venous pressure trends (VPTs), ...

We report two cases of venous air embolism which occurred in association with infusion of Haemaccel(R) using a pressure bag. As a result of these incidents, we performed a study that showed that up to 45 ml of air can be infused into a patient from a pressurised Haemaccel(R) plastic ...

OBJECTIVE: Because the skin of the groin is often spared, femoral central venous catheters are sometimes used in patients with extensive burns. The accuracy of central venous pressures obtained from the infradiaphragmatic location relative to the traditional supradiaphragmatic value is not known in this population. METHODS: Seventeen seriously injured but ...

The effects of subarachnoid administration of the alpha 2-agonists xylazine and medetomidine on haemodynamic parameters in six adult goats were evaluated. Xylazine (0.05 mg/kg body wt) or medetomidine (0.01 mg/kg body wt) was administrated in the lumbosacral subarachnoid space. Mean arterial blood pressure and central venous pressure and electrocardiograms were ...

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 ...

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 ...

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 ...

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, ...

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 ...

BACKGROUND: The fibrinolytic system may play an important role in the development and progression of peripheral arterial occlusive disease. PATIENTS AND METHODS: 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 ...

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 ...

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 ...

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 ...

PURPOSE: 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 ...

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 ...

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 ...

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 +/- ...

PURPOSE: 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. METHODS: Since 1990, we have studied 61 patients after ...

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, ...

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 ...

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. ...

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 ...

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, ...

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 ...

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 ...

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 ...