Experimental models of deep venous thrombosis, heretofore, have not been available for laboratory studies. This investigation establishes a novel model of venous thrombosis by inhibiting the protein C system combined with venous stasis and subtle venous injury. Ten adolescent baboons were studied in pairs, with one animal receiving saline solution ...

A total of 50 patients with impotence underwent cavernosometry and cavernosography with intracavernous injection of vasoactive drugs. Several hemodynamic parameters were analyzed, including the pressure response curve after injection of vasoactive drugs and infusion of saline, the volume required to achieve erection, venous outflow resistance, erection maintenance infusion rate, rate ...

Twelve patients with peripheral arterial occlusive disease were evaluated prospectively in an effort to further investigate the etiology of pedal and lower leg edema that occurs following revascularization (e.g., aorto-iliac or femoropopliteal bypass). Serum total protein, albumin, blood urea nitrogen, and creatinine levels were measured (in addition to peripheral venous ...

Venous pulsations are thought, but to our knowledge have never been demonstrated, to result in underestimation of oxygen saturation measured by pulse oximetry (SpO2); however, to our knowledge, this has never been demonstrated. A patient with ischemic cardiomyopathy requiring intra-aortic balloon counterpulsation (IABC) had to withstand a temporary cessation of ...

A commercially available double-lumen central venous catheter that can be inserted over a 0.018-inch guide wire was used for ureteral perfusion studies in three infants. Complications or difficulties were not encountered in any patients. This technique allows simultaneous monitoring of perfusion and intrarenal pressure and requires only a single puncture ...

One hundred thirty-seven limbs with venous obstruction were analyzed. The arm/foot venous pressure differential and reactive hyperemia tests were found to be useful techniques to diagnose and grade venous obstruction. Traditional techniques including venography and ambulatory venous pressure are inferior in this regard. The newer techniques have provided newer insights ...

A model of rat arteriovenous fistula (AVF) was created using a proximal common carotid artery to distal external jugular vein anastomosis. Anatomical dissections revealed that the external jugular vein is the primary vessel draining intracranial venous blood. Physiological measurements were made with the AVF open and closed, and during venous ...

Twenty-five buffalo calves (age: 14 +/- 1.9 months; body weight: 102 +/- 9.4 kg) were subjected to intravenous regional analgesia (IRA) of the hind limb with 2% lignocaine HCl (4 mg/kg b.w.), infused through the dorsal digital vein. In control animals 15 ml of normal saline was infused. The effect ...

Venous pressure measured at the venous bubble trap (VPdm) is a complex function of true intra-access pressure (VP0), hematocrit, needle gauge, and blood flow. In a patient free circuit, needle gauge, hematocrit, and blood flow influenced the pressure drop through the venous return needle. Measured intra-access pressure (VPm) and VPdm ...

The pedicled venous flap is used at various sites, such as the finger, forearm, and leg. The authors previously reported that the reasons for the viability of such flaps, based on the digital dorsal vein and used for repairing digital skin defects in the earlier study, were high venous pressure ...

The relation between the capacitance response (regional blood volume mobilization) and the venous resistance response, i.e. the two main functions of the venous system, was investigated during graded sympathetic nerve excitation in cat gastrocnemius muscle under well defined experimental conditions. The neural capacitance response was also compared with the total ...

To determine viscoelastic features of the rat hindquarters vasculature, we measured pressure-volume curves. Male Wistar rats were transected at the lumbar level, and the perfused hindquarters were oxygenated with a hollow fiber artificial lung. The blood volume was measured by counting 51Cr-labeled red cells led to a gamma counter through ...

Leg ulcers are a well recognized complication of sickle cell disease that has been attributed to venous insufficiency. We studied 16 patients with sickle cell disease and active ulcers using venous pulse volume recordings and photoplethysmography (Doppler studies). Based on hemodynamic monitoring, all 16 patients exhibited rapid refilling times, findings ...

Noninvasive diagnosis of axillary and subclavian venous thrombosis or documentation of the post-thrombotic syndrome using modalities currently in use is not definitive. Light reflection rheography, which is a reflection of venous pressure changes in the extremity as recorded from the subdermal capillary plexus, was used to correctly diagnose axillary or ...

Venodilatation may be an important property in drugs used to treat heart failure. Deductions about venous tone from standard hemodynamic studies may be misleading since filling pressures may be reduced by improved left ventricular function. To study the venodilator properties of drugs, we have modified a radionuclide blood pool method ...

The efficacy of a controlled-release topical dosage form of glyceryl trinitrate (Nitroglycerin Transdermal Therapeutic System, Nitroderm TTS, NTG-TTS; CAS 55-63-0) was studied in the experimental model of congestive heart failure in beagles. NTG-TTS suppressed the increase in left ventricular end-diastolic and central venous pressure, and total peripheral resistance resulting from ...

In this study, we present a new approach for using the pressure vs. time data obtained after various vascular occlusion maneuvers in pump-perfused lungs to gain insight into the longitudinal distribution of vascular resistance with respect to vascular compliance. Occlusion data were obtained from isolated dog lung lobes under normal ...

Intramuscular pressures were measured in the anterior tibial muscle with the microcapillary infusion method in 10 patients (11 limbs) with deep venous valvular insufficiency. The results were compared with pressure measurements in healthy controls (n = 8) and in patients with only superficial venous insufficiency (n = 7). The technique ...

Approximately 25% of patients with stasis ulceration have normal or below normal ambulatory venous pressures. A reflux index was calculated by multiplying postexercise pressures by Valsalva-induced foot venous pressure elevation. In patients with stasis ulceration, reflux index was found to have an excellent negative predictive value with a clear discriminant ...

The aim of this study was to understand the possible mechanisms by which deep venous insufficiency and venous hypertension are associated with trophic skin changes and ulceration and to explain the therapeutic effect of Pentoxifylline in patients with leg ulcers due to deep venous incompetence. Twenty patients were included in ...

The authors investigated, in vivo, the effects of four vasodilators on venous tone in dogs. Baseline venous tone was determined from the pressure: diameter relationships in the inferior vena cava (VSIVC) and femoral vein (VSFV) as measured during several seconds of occlusion of the proximal inferior vena cava. All of ...

Plugging of skin capillaries by activated white blood cells is one of the proposed mechanisms by which skin damage may be initiated in chronic venous insufficiency. The aim of this study was to determine whether a microcirculatory deficit was induced in the skin by raising the venous pressure proximally for ...

Venous congestion is a constant threat in the survival of free flaps, pedicled flaps, tissue replantations and traumatized tissue. Leech therapy has proved effective in salvaging much of these compromised tissues. To be effective, leeches must be both readily available and hungry, requirements not always easily met. Our investigation seeks ...

To provide a better understanding of analysis of arterial (AO) and venous occlusion (VO) tracings, using a constant and nonpulsatile perfusion pressure system, we set up an isolated in situ dog lobe preparation perfused with autologous blood. Four signals were recorded: arterial pressure, arterial inflow rate, venous pressure, and venous ...

Thirty-two patients in whom Legg-Perthes disease apparently involved only one hip were examined with venography, measurement of intraosseous and intra-articular pressures, arthrography, and dynamic triphasic bone-imaging with 99mTc methylene diphosphonate. The arterial flow of blood in the affected femoral head was slightly decreased, but the difference from that on the ...

The relationship between the arterio-venous pressure gradient and blood flow - the Hagen-Poiseuille principle - was reinvestigated. A main theme was to compare transmural pressure changes induced by either changing pressure inside or outside the vessels. Blood flow was measured in subcutaneous and skeletal muscle tissue in the lower limb ...

A two-stage project was developed to study the effect of increased venous pressure on blood flow and survival in microvascular free tissue transfers. A rabbit epigastric fasciocutaneous free flap model was used. The blood flow in the rabbit epigastric free flap is 1.07 +/- 0.06 ml/min. The average venous pressure ...

The purpose of this study was to examine the effects on the skin microcirculation of a short period of venous hypertension. 34 subjects (17 patients with lipodermatosclerosis and 17 controls) were studied. Laser-Doppler flowmetry was used to assess the hyperaemic responsiveness of the skin following three minutes of ischaemia. This ...

Fifty cases admitted to the urological clinics of Turkish State Railways Hospital, Ankara, were examined by scrotal ultrasonography in order to find the relationship between the left spermatic vein diameter measured by ultrasound and palpated varicocele and Doppler ultrasound findings. In the measured 5-6 mm spermatic vein diameters palpable varicocele ...

An analysis of the rat apical periodontal ligament (PDL) microvascular bed and fenestrae was conducted to evaluate the effect of a continuous 1.0 N intrusive tooth load for 30 minutes. The microvascular bed consisted of postcapillary-sized venules, venous and arterial capillaries, and terminal arterioles. Intrusion produced significant increases (p less ...

OBJECTIVE: This study measured the internal jugular vein and right atrium pressures during pediatric CPR to detect and quantify venous pressure gradients across the thoracic inlet. DESIGN: Ten children from 2 months to 15 years old who underwent CPR had simultaneous pressure measurements recorded from the right atrium and jugular ...

The distensibility of the forearm veins in 24 patients with congestive heart failure was studied by occlusion plethysmography. Relationships between forearm venous distensibility and symptoms, hemodynamic data obtained by right heart catheterization and plasma levels of vasoactive hormones were evaluated. Forearm venous pressure (VP) and volume change (delta V) were ...

1. Complete blood counts, respiratory rate, tidal volume, arterial and mixed venous blood gases; heart rate, cardiac output, and arterial, pulmonary artery, central venous and pulmonary wedge pressures were determined in 10 pregnant adult sheep of 42.7-65.7 kg body weight. 2. Arithmetic means, standard deviations, and coefficients of variation were ...

Venous congestion in bone is a common early feature of inflammatory and degenerative joint diseases. An experimental study was performed of the relationship between the scintigraphic appearance of joints and the intraosseous hemodynamics during venous congestion caused by obstruction of the osseous venous drainage by increased intra-articular pressure. Intra-articular pressure ...

To determine the effect of elastic compression stockings on deep venous hemodynamics we measured ambulatory venous pressure, venous refill time, maximum venous pressure with exercise, amplitude of venous pressure excursion, and duplex-derived common femoral and popliteal vein diameter and peak flow velocities with and without stockings in 10 healthy subjects ...

A procedure involving the parallel perfusion of deep veins in a cat shank preparation with endogenous blood and a constant volume of dextran solution has been devised. The dextran is supplied to these deep veins via superficial and communicator veins (venae communicantes). With this method it is possible to record ...

The effects of changes in abdominal pressure (Pab) on inferior vena cava (IVC) venous return were analyzed using a model of the IVC circulation based on a concept of abdominal vascular zone conditions analogous to pulmonary vascular zone conditions. We hypothesized that an increase in Pab would increase IVC venous ...

The effect of magnesium sulphate (MgSO4) infusion on blood pressure and circulating venous catecholamine levels in 8 patients with severe gestational proteinuric hypertension is described. A significant fall in blood pressure was noted after MgSO4 infusion; the maximal fall in diastolic blood pressure correlated with the greatest rise in serum ...

Using 793 limbs with nonobstructive venous reflux, we evaluated a number of techniques used for the assessment of venous reflux. The venous Doppler examination was found to be a reliable screening tool with excellent sensitivity and good specificity. Photoplethysmography was 97% sensitive in patients with ambulatory venous hypertension; however, in ...

A total of 171 sets of chest radiographs chosen randomly were reviewed independently by two residents in their second year of training, and two experienced radiologists. The degree of interobserver agreement in an overall assessment of pulmonary venous hypertension and in the assessment of five signs, indicative of pulmonary venous ...

OBJECTIVE: To assess the hemodynamic determinates of peripheral subdiaphragmatic venous-to-right-heart return during closed-chest CPR. MODEL: Seven anesthetized dogs subjected to electrically induced ventricular fibrillation for five minutes. INTERVENTIONS: Conventional closed-chest CPR and closed-chest CPR with continuous abdominal binding at a chest compression rate of 60 per minute, a compression-to-relaxation ratio ...

Increased mean arterial pressure during the aortic crossclamp period while on cardiopulmonary bypass was usually treated by us with hypotensive drugs. We noticed, however, that aspirating shed excess pulmonary venous blood from the open pleural cavities causes an immediate reduction in mean arterial pressure, obviating the need for any further ...

Using a previously developed canine model of erection, we measured pudendal artery and venous flow as well as pressure in the corpora cavernosa, glans penis, pudendal artery and vein. Penile erection was induced by pelvic nerve stimulation. Arterial flow increased by a factor of 2.5 within two seconds after the ...

The quality of donor organs will determine the quality of life for the recipient and the importance of optimal management of the multi-organ donor is that the organs may benefit up to five, critically ill, patients. The basic principle is to maintain sufficient preload to minimise the need for inotropic ...

Mixed venous oxygen saturation (SvO2) monitoring was used to assess tissue and circulatory recovery following induced ventricular tachycardia or fibrillation in 17 patients undergoing surgery for automatic implantable cardioverter-defibrillator (AICD) placement. Return of systemic arterial pressure conventionally determines adequate recovery. The duration of circulatory arrest during defibrillator threshold (DFT) testing, ...

To determine the role of the venous outflow restriction during human erection, we compared intracavernous pressure with deep dorsal vein pressure in 6 normal subjects during papaverine-induced erection and penile saline infusion. In addition, flows necessary to produce and maintain erection were measured in 10 cadavers before and after resection ...

STUDY OBJECTIVE: To determine the diagnostic criteria (phase I) and to assess the accuracy (phase II) of an objective Doppler-Valsalva pressure method as compared with contrast venography for the diagnosis of acute deep-leg-vein thrombosis in symptomatic outpatients. DESIGN: A two-phase prospective study in consecutive patients. Doppler ultrasound strip-chart recordings and ...

The effects of portal hypertension on gut function may be mediated by venous congestion and altered circulating levels of enteric hormones and neuropeptides. We designed this study to determine the effects of chronic intestinal venous hypertension (VHT), in isolation, on gut motility and absorption. In 10 dogs, a 20- to ...

The autoregulating vascular bed of the isolated canine extensor digitorum longus muscle was investigated for the possible existence of two positive zero-flow pressure axis intercepts, a tone-dependent one and a tone-independent one. An isolated preparation, perfused with autologous blood, was used to exclude effects of collateral flow and nervous and ...

Cerebral blood flow (CBF) was determined in humans at rest and during four consecutive unilateral static contractions of the knee extensors. Each contraction was maintained for 3 min 15 s with the subjects in a semisupine position. The contractions corresponded to 8, 16, 24, and 32% of the maximal voluntary ...