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Hemodynamic deterioration in chronic venous disease.

Clinical deterioration of patients with chronic venous disease (CVD) has been well described and a standardized classification has been proposed. The progressive hemodynamic deterioration producing these clinical findings is less well appreciated. This study examines and correlates venous hemodynamics with clinical severity in patients with CVD. Two hundred seventy-four extremities from 149 patients with varying degrees of CVD and 56 extremities from 28 symptom-free volunteers were evaluated clinically and hemodynamically. Each limb was assessed for functional venous volume, degree of valvular insufficiency, efficiency of the calf muscle pump, and noninvasive estimate of ambulatory venous pressure. In addition, exercise venous pressures were recorded in 56 extremities from 36 patients and 9 extremities from 6 volunteers. As CVD progresses from class 0 to class 2, venous volume expands, valvular function deteriorates, the calf muscle pump becomes inefficient, and ambulatory venous hypertension develops. However, once extremities develop brawny edema or hyperpigmentation, further deterioration of limb hemodynamics does not occur. Patients with deep venous obstruction have more severe valvular insufficiency, calf muscle pump dysfunction, and ambulatory venous hypertension than have patients without evidence of obstruction. Residual volume fraction offers a reliable noninvasive estimate of ambulatory venous pressure (r = 0.76), although its correlation was significantly better for patients without venous obstruction (r = 0.86) than for those with obstruction (r = 0.40; p < 0.05). Deterioration in venous hemodynamics parallels clinical severity through class 2. Once brawny edema and hyperpigmentation occur, ulceration develops without additional deterioration of venous hemodynamics.

Adult↗

[The influence of coronary artery bypass graft surgery on cerebral hemodynamics].

The influence of coronary artery bypass graft surgery (CABGS) on cerebral hemodynamics is still understudied. At the same time, ischemic heart disease (IHD) is often comorbid to atherosclerotic carotid artery stenosis, with significantly higher risk of post CABGS cerebrovascular complications in patients with cerebral hemodynamics lesion. Indices of cerebral hemodynamic reserve have been studied in 40 patients with severe IHD before and after CABGS. In most patients, there was a significant postoperative improvement of cerebral hemodynamics related to enhancing of blood flow along medial cerebral arteries and to amelioration of the parameters of cerebral hemodynamic reserve. But CABGS did not positively impact on cerebral hemodynamics in patients with initially reduced ejection fraction that appears to be a consequence of insufficient increase of stroke volume and in patients with a history of ischemic lesions of cerebral blood circulation. Therefore, the results obtained suggest a close relationship between coronal and cerebral blood circulation that should be taken into account in the analysis of pathogenetic mechanisms of cerebral blood circulation lesion in patients with IHD as well as in elaboration of adequate individual preventive treatment measures.

Adult↗

[Clinico-hemodynamic typification of alcoholics with various central circulatory disorders].

A study was made of the clinical picture of autonomic-somatic++ components of alcoholic abstinence and delirium as well as of the role of cardiovascular (hemodynamic) deviations. Using tetrapolar chest rheography the main types of hemodynamic disorders were described on a material of a random examination of 137 patients with stage II and III alcoholism. Of these, 64 patients were with the abstinent syndrome and 73 with the delirious syndrome according to the growth of the status gravity. Analysis of the clinical picture of the disease was first performed over time on the basis of the clinico-hemodinamic + parameters and phases of hemodynamic decompensation. The role of alcoholic cardiomyopathy in the general structure of the cardiovascular and somatovegetative manifestations was shown as dependent on variants of abstinence and delirium. Based on three clinico-hemodynamic++ types equivalent to the types of hemodynamic disorders, a new approach was applied to the differentiated treatment of alcoholic patients depending on their individual features, using optimally computed drug doses influencing the hemodynamics.

Adult↗

[Hemodynamic aspect of post ECC cardiac failures. Study of 193 cases].

The aim of this study is to define the hemodynamic characteristics of this "clinical model" of acute cardiac failure observed after cardiac surgery carried out under extra-corporeal circulation, which constitutes the essential cause of "post-operative low cardiac output syndrome". The 193 patients in this study make up a representative sample of patients operated, treated and studied according to a homogeneous methodology for a period of 1 year. The clinical analysis of the post-operative circulatory condition, after exclusion of non cardiogenic syndromes, led to grouping the cases into 5 classes of circulatory change of increasing severity, each corresponding to a specific "therapeutic necessity". The hemodynamic results (intra-vascular pressures, oxymetry, cardiac output by "Cardio-Green" dilution method) are given for each of the five classes, thus defining the "hemodynamic profile" and the statistical reliability of the main objective parameters. This gives proof of the therapeutic indications for the main therapeutic procedures actually known, for which we prevent the hemodynamic effects noted for each of them. Thus, three "degrees of cardiac failure" are found: less severe (classes I and II) call for simple metabolic equilibration and possibly diuretics: the systolic work is above 160 gm/m2. Decompensated circulatory failure (classes III and IV) corresponds to a more important reduction in systolic work (9) 15 gm/m2, i.e. between 20 et 40 p. 100 of the basal value), and call for sympatho-mimetic cardiotonic agents: isoprenaline and/or dopamine. Below this value, in spite of medical treatment, the hemodynamic situation can still be sometimes reversible under circulatory assistance (diastolic counter pressure by means of an aortic balloon). Confronted with the clinical picture, the hemodynamic study enables the quantification of the circulatory change, and specification of the cardiogenic part and thus especially helps the carrying out of the treatment.

Adolescent↗

Hemodynamic monitoring in ICU.

Oxygen supply to all tissues is possible only in a condition of adequate blood circulation. Oxygen demand is the driving force that is responsive of hemodynamic adjustment. The human body acts on four modulators (intravascular volume, inotropy, vasoactivity, chrono-tropy) in order to adjust the hemodynamic state. Hemodynamic monitoring consists of techniques able to assess the hemodynamic status and to understand the mechanism of patient decompensation; its goal is to maintain adequate tissue perfusion through appropriate therapeutic interventions. An early diagnosis of hemodynamic alteration is crucial for an early treatment; several reports have explored the effectiveness of hemodynamic manipulations and results are conflicting: too many variables can, in fact, modify the results: timing and lenght of the treatment, drugs used, etc. However, at least, in some specific settings, as sepsis, early intervention has a positive impact on mortality. In this presentation it will be briefly analyzed the most common parameters used in the ICU. Arterial pressure, central venous pressure, pulmonary artery catheter derived parameters, SvO2 and their relation with organ perfusion are considered and positive and negative aspects of this type of monitoring is reviewed. Starting from these considerations we would like to underline the importance of understanding the physiological basis of monitoring and the correct interpretation of data in order to have improvement on patient outcome.

Critical Care↗

[Hemodynamic findings after retinal interventions].

In this study we tried to find out if the hemodynamic results could help us explain why the visual situation after retinal surgery often becomes unsatisfactory despite good anatomical results. Using Ulrich's methods (oculo-oscillodynamography), we measured the hemodynamic parameters-especially ciliary perfusion pressure and the volume of blood flow--in 40 patients after retinal surgery. One of our results is remarkable: there is a direct relationship between the amount of scleral buckling and a disturbance in the hemodynamic parameters. Otherwise, we found that hemodynamic disturbances after vitreous surgery (vitrectomy, silicone oil implant or gas) are less dramatic than after buckling methods or in connection with them. Also, the hemodynamic disturbance begins before retinal surgery, obviously according to the stage of ablation: with or without macular involvement and irrespective of the time of retinal detachment. After all we have demonstrated in this study, we have reason to believe that a disharmony in the ocular hemodynamics causes disappointing visual results, often seen after retinal surgery.

Adult↗

[The acute, chronic continuous after treatment and chronic intermittent with a variable therapeutic window (4 and 6 hours) hemodynamic effects induced with transdermal nitroglycerin in patients with congestive heart failure].

The aim of this study was to assess the minimum time interval necessary to avoid the development of tolerance during nitroglycerin patch application. We studied 24 patients, aged 23 to 73 years, with ischemic or idiopathic dilated cardiomyopathy (LV EF less than 0.40) and stable clinical conditions during 30 days before the study. All patients had significant reduction of systemic and pulmonary arterial pressure after sublingual nitroglycerin. After the hemodynamic assessment of the response to the first dose of the nitroglycerin patch, the patients were randomized to 1 of 3 chronic treatment groups: continuous patch application (Group A), intermittent application with 4 hours intervals (Group B), intermittent application with 6 hours intervals (Group C). All patients were studied by right heart Swan-Ganz catheterization; the hemodynamic response to a 10 mg multilayer matrix nitroglycerin patch was assessed before and every hour, in the next 4 hours, after both the first application of the patch and after 1 month of therapy; after chronic intermittent therapy, hemodynamic parameters were also measured 24 hours after drug withdrawal. Hemodynamic parameters were significantly changed after the first nitroglycerin patch application: particularly, mean systemic arterial (MAP), right atrial (RAP) and pulmonary wedge pressures (PWP) declined from 96 +/- 10, 8.9 +/- 1.8 and 20.1 +/- 5 to 81 +/- 6, 4.7 +/- 1.5 and 12.2 +/- 3 mmHg (-15.6, -47.2 and -59.3%, respectively); systemic vascular resistance (SVR) and heart rate (HR) were reduced from 1645 +/- 121 to 1288 +/- 89 dyne.s.cm-5 and from 85 +/- 7 to 81 +/- 7 b/min; lastly, cardiac index (CI), stroke volume (SVI) and stroke work index (SWI) increased from 2.3 +/- 0.3, 28.2 +/- 5 and 28.7 +/- 9 to 2.7 +/- 0.3 l/min/m2, 33.3 +/- 5 ml/min/m2 and 31.5 +/- 8 g.m/m2 (+17.4, 18.1 and 9.7%). After 1 month of either continuous or intermittent patch application with 4 hours intervals, hemodynamic parameters returned to control values with no significant change after patch application. In contrast, after intermittent patch application with 6 hours intervals, a persistent hemodynamic response to nitroglycerin patches was still present.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Cutaneous↗

Glomerular hemodynamic effects of dietary polyunsaturated fatty acid supplementation.

Dietary supplementation with polyunsaturated fatty acids (PUFAs) has been shown to alter the course of experimental renal disease. Although hemodynamic factors such as glomerular hypertension are felt to be important in the progression of renal disease, the effects of dietary PUFA supplementation on glomerular hemodynamics are unknown. The present investigation, therefore, was designed to evaluate the glomerular hemodynamic effects of dietary PUFA supplementation in normal rats. Male Sprague-Dawley rats were fed standard chow supplemented with either 20% (wt/wt) fish oil (FO) as a source of omega-3 PUFAs, 20% sunflower oil (SO) as a source of omega-6 PUFAs, or 20% coconut oil (CO) as a control diet. Micropuncture studies were performed after 4 to 6 weeks of dietary supplementation. Compared with CO rats, SO rats did not demonstrate any changes in glomerular hemodynamics. However, rats supplemented with FO demonstrated significant (p less than 0.05) increases in both single nephron glomerular filtration rate and single nephron plasma flow. These hemodynamic changes were not associated with alterations in glomerular capillary hydraulic pressure or the glomerular ultrafiltration coefficient. The increase in SNPF was primarily the consequence of a 37% reduction (p less than 0.05) in efferent arteriolar resistance. Thus dietary FO supplementation resulted in glomerular hyperfiltration and hyperperfusion. These hemodynamic actions may have important consequences in determining the effect of omega-3 PUFAs on the course of experimental and clinical renal disease.

Animals↗

[Hemodynamic types in pilots and their clinical and expert-evaluation significance].

At the present time two approaches to the hemodynamics types can be distinguished in the literature: some authors maintain that they are variants of the norm, while others claim that they emerge in the course of disease. The purpose of the present investigation was to study the different viewpoints and to clarity the clinical and diagnostic role of hemodynamics types in aviation medicine. Altogether 293 pilots were examined, 49 of which were essentially healthy and 244 had various cardiovascular pathologies. It was found that the percentage ratio of the hemodynamics types in the subjects with neurocirculatory dystonia of the hypertensive type, stage I hypertensive disease, myocardiodystrophy and myocarditic myocardiosclerosis was the same (p less than 0.05) as in the healthy pilots. This indicates that hemodynamics types do not originate during disease, being rather variations of the norm. During orthostatic tests some subjects exhibited transition of one hemodynamic type to the other (e. g., hyperkinetic-to-eukinetic type transition, p less than 0.05); however, during the very first minute after exposure 90% of the subjects displayed their inherent types which pointed to their stability. Identification of the hemodynamics types in combination with measurement of central and peripheral circulation as well as bioelectric activity of the heart at rest and during orthostatic tests can improve the sensitivity of methods used to detect pathological changes at early stages and help to choose adequate rehabilitation procedures.

Adult↗

[Hemodynamic effects of anesthetic agents and bypass flow during orthotopic liver transplantation in pigs].

Although the hemodynamics during orthotopic liver transplantation is unstable, it is very important for new liver to get well-controlled hemodynamics. Thus hemodynamic changes were studied, especially in relation to the influence of anesthetic agents and bypass flow in orthotopic liver transplantation in pig. Hemodynamic changes associated with NLA, GOS (sevoflurane) and GOF anesthesia were evaluated. It was difficult to maintain arterial pressure and to recover cardiac output with NLA after the bypass was removed. GOS, with which the hemodynamic condition was best maintained and no hepatotoxicity was manifest, proved the most useful of the three anesthetic agents. Hemodynamic studies based on bypass flow were made by comparing two groups, a high flow (31 +/- 4ml/kg/min) and a low flow (19 +/- 2ml/kg/min) groups, following the bypass model study conducted by 20, 30 and 40ml/kg/min. flow rates with the fixed infusion speed. In the high flow group, cardiac output and pulmonary arterial pressure were better maintained during the anhepatic phase and at the removal of the bypass. It is estimated that the low flow group was within the limits permitted, but beyond safety limits, also from the bypass model study. It is suggested that approximately 30ml/kg/min was the appropriate flow rate in pig.

Anesthetics↗

[Hemodynamic study at the bedside of patients with acute myocardial infarction over 60 years of age].

Aiming to study the hemodynamic behavior of the aged during the first 36 hours after acute myocardial infarction (AMI), 41 patients of at least 60 years at age (63.3 +/- 3) were submitted to a bedside hemodynamic study, through a Swan-Ganz catheter. The results obtained for the different variables (right atrial pressure, right ventricular pressure, pulmonary-arterial pressure, pulmonary-capillary, cardiac index, systolic index, left and right ventricular performance, and systemic pulmonary-arterial resistance) were compared to those of 39 individuals with age less than 60 years (49.6 +/- 1.5). It was also considered the electrocardiographic localization of the infarcted area. Eventual differences in the distribution of frequency of the individuals were also investigated, considering the four clinical-hemodynamic groups proposed by Forrester. Upon separate analysis of the hemodynamic variables, the results did not reveal significant differences between the younger and the older. However, by Forrester's classification, it was observed a significantly higher number of aged patients in group III (hypovolemic). Therefore, there was a tendency in the aged to present hypovolemia during the first 36 hours after myocardial infarction. The difficulties to recognize this status clinically and its prognostic importance justify the performance of hemodynamic bedside study in elderly with acute myocardial infarction with hemodynamic instability.

Aged↗

[Measurement of the portal blood flow in man by continuous local thermodilution method: II. Portal hemodynamics before and after hepatectomy].

We found that measurements of portal blood flow by continuous thermodilution were highly reproducible even after hepatectomy. Our subjects numbered 59 in all: In these patients having diseases of the liver and biliary tract, we studied portal hemodynamics during percutaneous transhepatic portography. Of these, 37 underwent hepatectomy. We chose 19 subjects from this group, and measured again both portal venous flow and portal venous pressure many times, continuing for 14 more days. In all 19 patients checked after hepatectomy, portal hemodynamics became hypodynamic, and this change was greater when the amount of liver resected was large. In 18 of these patients, hemodynamics started to improve after the 7th postoperative day. Changes in hemodynamics were not significantly different in patients with or without cirrhosis. In one patient who died of hepatic failure, the portal hypodynamic state did not improve. With this exception, in patients with major resections, portal venous flow per liver volume had increased after surgery and continued to increase. This was not true for patients with minor resections. Portal hemodynamics are important in the functioning and regeneration of the remaining liver, and it is necessary to understand and medically correct portal hemodynamics before and after hepatectomy.

Adult↗

Comparison of the acute hemodynamic effects of ibopamine and dopamine in chronic congestive heart failure.

The acute hemodynamic effects of ibopamine (SB-7505), the 3,4-diisobutyryl ester of N-methyldopamine which can be administered orally, were compared with those of dopamine. Ten male patients aged 54 years on average, with chronic congestive heart failure in NYHA (New York Heart Association) classes II-IV were studied. Eight of them were suffering from idiopathic congestive cardiomyopathy and two from ischemic cardiopathy. Baseline hemodynamic parameters were recorded within 24 h after withdrawal of previous treatment, the patients being kept on digitalis only. The investigation was carried out for a period of 3 days running. On day 1 of treatment one group of 5 patients were given dopamine at increasing doses of 2, 4 and 6 micrograms/kg/min. Their hemodynamic parameters were assessed 15 min after each dose and 15 and 60 min after withdrawal of the drug. Ibopamine was then administered orally in single doses of 50 mg on day 2 and 100 mg on day 3. The hemodynamic parameters were evaluated at 30, 60, 90, 120, 180, 360 and 480 min after administration. On day 1, another group of 5 patients were given 50 mg ibopamine, on day 2, 100 mg ibopamine and on day 3, dopamine. Hemodynamic data in this group of patients were evaluated at the same times mentioned above. The hemodynamic effects of ibopamine 100 mg are very similar to those obtained with 4 micrograms/kg/min dopamine. Indeed, the effects of both drugs on the cardiac index, right atrial pressure, peripheral and pulmonary vascular resistance do not differ significantly from each other.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[External respiratory function, blood oxygenation and the biogenic amine content in different hemodynamic variants of hypertension].

Pulmonary ventilation and hemodynamics, ventilation/perfusion ratios, arterial blood oxygen and plasma biogenic amines were examined in 126 essentially hypertensive patients with different hemodynamic types. Changes in pulmonary ventilation and hemodynamics result in increased venous admixture in patients with eukinetic hemodynamics, but the arterial blood oxygen level only diminishes in the hypokinetic type. Increased venous admixture is due to a regional decrease in the ventilation/perfusion ratio which is largely dependent on pulmonary hemodynamic disorders. A direct correlation is demonstrated between arterial blood oxygen concentration and daily noradrenaline excretion in eu- and hypokinetic hemodynamic types. Arterial hypoxemia may be responsible for depressed sympathetic activity in patients with these circulation types.

Adolescent↗

Long-term follow-up of patients having infrainguinal bypass performed below stenotic but hemodynamically normal aortoiliac vessels.

Because infrainguinal bypasses performed on the basis of normal papaverine testing in patients with multilevel arterial occlusive disease are done below arteriographically diseased although hemodynamically normal vessels, there is concern about progression of suprainguinal disease compromising long-term success. This study has been done to assess the long-term results of such bypasses. Between 1979 and 1985, infrainguinal bypasses selected by papaverine testing were done on 92 limbs having hemodynamically normal inflow in the presence of arteriographically demonstrable aortoiliac stenoses of 15% to 70%. Long-term hemodynamic and clinical success rates were determined with criteria based on papaverine and noninvasive vascular testing. There was no significant difference in hemodynamic success at 48 months (by life-table analysis) (p = 0.98) when comparing limbs with less than 50% aortoiliac stenoses to limbs having 50% or greater stenoses. The difference between the mean degree of preoperative inflow stenoses for long-term hemodynamic successes (32.5% +/- 1.5%) and failures (34.6% +/- 3.0%) was not significant (p = 0.57). There was no significant difference (p = 0.98) in the number of subsequent inflow procedures required in limbs with preoperative aortoiliac stenoses of less than 50% (13.5%) vs. aortoiliac stenoses of 50% or greater (13.3%). Long-term results of infrainguinal bypass done below stenotic but hemodynamically normal aortoiliac vessels are not related to the amount of angiographically demonstrable inflow stenosis. Selection of patients for infrainguinal bypass on the basis of papaverine testing, irrespective of angiographic findings, eliminates unnecessary inflow procedures without detriment to long-term success.

Aged↗

Bedside hemodynamic monitoring in the cardiac care unit.

Bedside hemodynamic monitoring provides useful information regarding the differential diagnosis of the various pathologic mechanisms of low output syndrome. It also allows recognition of hemodynamic subsets of patients with acute myocardial infarction. Furthermore, hemodynamic monitoring is necessary for prompt evaluation of the response to therapeutic interventions in patients with low output syndrome. In patients with acute myocardial infarction, hemodynamic indices can also be used for evaluation of immediate prognosis. Because bedside hemodynamic monitoring is relatively safe, and with proper precautionary measures the potential complications can be avoided, hemodynamic monitoring should be considered in the management of all critically ill cardiac patients.

Coronary Care Units↗

[Combined disorders of the central and regional hemodynamics and microcirculation in myocardial infarct].

Central and regional hemodynamics was studied in 228 patients with acute myocardial infarction by a complex of radio-indication tests. It was established that the degree of changes in central hemodynamics correlates to a definite extent with the severity of myocardial involvement (size of the damaged zone). Regional hemodynamics did not always change parallel to the reduction in cardiac output. The character of circulation in the organs of patients with myocardial infarction depends greatly on the internal control factors and the degree of tonic tension of the regional vessels. Changes in the regional circulation in myocardial infarction lead to hypoxia of the organ and severe disturbances in its function. In most patients the intraorganic hemodynamics decrease gradient was 11/2-2 times more than the cardiac output reduction gradient. Hemodynamic changes in myocardial infarction at the level of different vessels are of a multicomponent and non-linear character. The extent and rate of restoration of intra-organic hemodynamics are greatly determined by the severity of myocardial infraction and the presence of complications.

Adult↗

Pneumococcal-induced pulmonary leukostasis and hemodynamic changes: role of complement and granulocytes.

In the present study we investigated the cardiopulmonary dysfunction caused by systemic pneumococcal (PNC) disease. We studied the hemodynamic and hematologic effects of intravascular challenge with nonviable PNC in normal, granulocyte-depleted, and genetically C3-deficient dogs. In normal dogs PNC administration caused a decrease in cardiac output (CO) of 58% (p less than 0.001), an increase in pulmonary vascular resistance (PVR) of 151% (p less than 0.02), and an increase in systemic vascular resistance (SVR) of 72% (p less than 0.02). The PNC challenge also caused significant decreases in both circulating granulocytes (-73%; p less than 0.02) and platelets (-58%; p less than 0.02). Histologic examination revealed granulocyte plugging within small pulmonary vessels. PNC challenge in granulocyte-depleted and C3-deficient dogs resulted in hemodynamic and hematologic changes that were not significantly different from those seen in normal PNC-challenged animals. Infusion of PNC-activated plasma resulted in hematologic changes that were not significantly different from those seen in PNC-challenged animals. Infusion of plasma treated with ethylenediamenetetraacetic acid (EDTA) prior to PNC incubation induced the same hematologic alterations but the hemodynamic response was less pronounced. To control for PNC constituents not removed by centrifugation and filtration, saline was incubated with PNC. After the PNC was removed, infusion of the saline induced no significant hemodynamic changes, although profound granulocytopenia occurred. We conclude that an intact complement system, but not normal numbers of circulating granulocytes, is essential to PNC-induced hemodynamic changes. PNC generates a plasma factor in vitro that does not require an intact complement system or cellular machinery to induce granulocytopenia without hemodynamic effect.

Animals↗