scholarly journals A Hemodynamic Study to Evaluate the Buffer Response in Cirrhotic Patients Undergoing Liver Transplantation

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Margarita Anders ◽  
Daniel Alvarez ◽  
Emilio Quiñonez ◽  
Federico Orozco ◽  
Nicolas Goldaracena ◽  
...  
Keyword(s):  
Blood Flow ◽  
Isosorbide Dinitrate ◽  
Liver Blood Flow ◽  
Resistance Index ◽  
Portal Blood Flow ◽  
Human Model ◽  
Physiological Regulation ◽  
Meal Ingestion ◽  
Artery Flow ◽  
Liver Transplant Recipients

The physiological regulation of the liver blood flow is a result of a reciprocal portal vein and hepatic artery flow relationship. This mechanism is defined as the hepatic arterial buffer response (HABR). This study was addressed to investigate whether HABR is maintained in denervated grafts in liver transplant recipients. Portal blood flow (PBF) and hepatic arterial resistance index (PI) were measured 6 months after transplantation using Doppler. In each patient we consecutively measured the vasodilator (Ensure Plus PO versus placebo) and vasoconstrictor (isosorbide dinitrate 5 mg SL versus placebo) stimuli. The meal ingestion caused a significant increase of both parameters, PBF (from 1495±260 to 2069±250 mL/min, P<0.05) and PI (from 0.7±0.2 to 0.8±0.2, P<0.05). By contrast, isosorbide dinitrate reduced PBF (from 1660±270 to 1397±250 mL/min, P<0.05) and PI (from 0.7±0.2 to 0.5±0.2, P<0.05). We show that PBF and PI are reciprocally modified with the administration of vasoconstrictor and vasodilator stimuli. These results suggest the persistence of the HABR in a denervated human model, suggesting that this mechanism is independent of the regulation from the autonomic nervous system.

Role of ethanol metabolism in the ethanol-induced increase in splanchnic circulation

1986 ◽  
Vol 250 (4) ◽  
pp. G518-G523 ◽  
Author(s):  
J. P. McKaigney ◽  
F. J. Carmichael ◽  
V. Saldivia ◽  
Y. Israel ◽  
H. Orrego
Keyword(s):  
Blood Flow ◽  
Liver Blood Flow ◽  
Portal Blood Flow ◽  
Splanchnic Blood Flow ◽  
Ethanol Metabolism ◽  
Radioactive Microsphere ◽  
Splanchnic Hemodynamics ◽  
Radioactive Microsphere Technique ◽  
Blood Flow Increase

In this study we report the effect on splanchnic hemodynamics of acute oral ethanol at doses ranging from 0.25 to 4.0 g/kg body wt. Flows were determined by use of a radioactive microsphere technique. Ethanol was found to increase portal blood flow by 23-57%. In awake rats this increase reached a plateau at the 0.5 g/kg dose. In ketamine-anesthetized rats, the increase was observed only at doses of 3.0 g/kg or more, with the response at doses of 0.5, 1.0, and 2.0 g/kg being suppressed by ketamine. Inhibition of alcohol dehydrogenase by intra-arterial administration of 4-methylpyrazole resulted in suppression of the liver blood flow increase after ethanol was administered to awake animals. Ethanol in the range of doses studied did not result in changes in blood glucagon levels. Rats fed ethanol-containing diets for 4 wk and withdrawn for 18 h had the same response to acute oral ethanol as did naive rats. It is suggested that ethanol metabolism mediates the effects of ethanol on splanchnic blood flow. An increase in splanchnic blood flow when concurrent with an increase in liver O2 consumption induced by ethanol might protect the liver from hypoxic damage.

Effect of Peroral Administration of Isosorbide Dinitrate on Portal Pressure and Blood Flow in Patients with Cirrhosis of the Liver

1989 ◽  
Vol 17 (6) ◽  
pp. 560-564 ◽  
Author(s):  
J. Cervinka ◽  
V. Kordac ◽  
M. Kalab
Keyword(s):  
Blood Flow ◽  
Hepatic Vein ◽  
Isosorbide Dinitrate ◽  
Slow Release ◽  
Portal Pressure ◽  
Blood Flow Rate ◽  
Portal Blood Flow ◽  
Peroral Administration ◽  
Oesophageal Varices ◽  
Wedged Hepatic Vein Pressure

The effect of slow-release isosorbide dinitrate, given orally four times daily for 14 days, on the portal circulation was studied in 10 patients with liver cirrhosis and oesophageal varices. Mean arterial pressure and heart rate were not influenced significantly by isosorbide dinitrate. Statistically significant dilation of the portal vein by 11.9% and an increase in blood flow velocity by 35.4% and in portal blood flow rate by 54.3% were observed at the end of therapy. The average wedged hepatic vein pressure was 32.9 mmHg before therapy and after therapy it was decreased to 60.5%. The slight decrease observed in free hepatic vein pressure was not statistically significant. Before treatment the portohepatic gradient was four times above normal and after therapy it fell to 9.5 mmHg. The results indicate that, in patients with portal hypertension, an improvement in haemodynamics can be achieved by the use of isosorbide dinitrate. This improvement may lead to the prevention of bleeding from oesophageal varices.

Distensibility of portacaval shunts in portal hypertensive cats: index of contractility model

1994 ◽  
Vol 72 (6) ◽  
pp. 687-692
Author(s):  
Andrés C. Inglés ◽  
Dallas J. Legare ◽  
W. Wayne Lautt
Keyword(s):  
Blood Flow ◽  
Venous Pressure ◽  
Resistance Index ◽  
Portal Blood Flow ◽  
Portal Blood ◽  
Total Occlusion ◽  
Shunt Resistance ◽  
Wide Range ◽  
Flow Through ◽  
And Control

Complete shunting of portal blood flow through portacaval shunts was obtained using a constrictor around the portal vein to gradually produce a total occlusion. After 4 weeks, acute experiments were conducted in anesthetized cats. Blood from the femoral artery was shunted through a pump to supply and control the entire portal blood flow. As shunted portal blood flow was varied over a wide range, the portal shunt resistance showed distensibility. Decreasing portal venous pressure from 15.0 ± 0.9 to 11.1 ± 0.6 mmHg (1 mmHg = 133.3 Pa) resulted in elevations of resistance of 58%. The relation between the resistance (R) and the distending pressure (Pd) was a constant, the index of contractility (IC), where IC = R∙Pd3. In steady state, the IC was 485 ± 55 mmHg4∙mL−1∙min∙kg and did not change passively in response to changes in portal blood flow. In conclusion, portacaval shunts are passively distensible, and resistance is altered as a cubic function of the distending pressure. Because resistance is altered both actively and passively, the IC should prove useful to differentiate these alternatives for evaluation of changes in portal hypertensive therapy.Key words: portacaval shunts, distensibility model, vascular resistance, index of contractility.

Pathophysiology of type A hypoxic lactic acidosis in dogs

1987 ◽  
Vol 253 (3) ◽  
pp. E271-E276 ◽  
Author(s):  
A. I. Arieff ◽  
H. Graf
Keyword(s):  
Blood Flow ◽  
Lactic Acidosis ◽  
Liver Blood Flow ◽  
Lactate Production ◽  
Arterial Lactate ◽  
Arterial Ph ◽  
Lactate Levels ◽  
Artery Flow ◽  
Arterial Po2 ◽  
Control State

Hypoxic lactic acidosis (HLA) was induced in dogs by ventilating them with a hypoxic gas mixture of 8% O2-92% N2. The animals were studied both in the control state and after development of HLA, where arterial lactate was above 5 mM, pH was below 7.2, bicarbonate was below 12 mM, and arterial PO2 was between 26 and 30 Torr. After hypoxia had been present for 90 min, most of the increase in arterial lactate vs. control was due to increased lactate production from gut and carcass in the presence of a decreased capacity of the liver to extract lactate. The capacity of the liver to extract lactate in the normoxic state was evaluated in another group of six dogs after infusion of L-lactic acid such that arterial pH, lactate, and bicarbonate were similar to hypoxic values. In these experiments it was found that the capacity of the liver to extract lactate was 14.8 +/- 1.7% of the delivered load vs. 4.9 +/- 1.3% observed in hypoxic animals. The decreased liver lactate extraction in HLA was probably secondary to both a decrease in liver oxygen uptake and a decrease in liver intracellular pH and was paralleled by an increase in liver tissue lactate levels. Cardiac output, in contrast to other forms of lactic acidosis, was increased by 40% vs. control and femoral artery flow by 35%, whereas liver blood flow was unchanged and renal blood flow decreased. Hypoxic lactic acidosis thus is the consequence of overproduction of lactate by both gut and carcass, in the presence of impaired utilization of lactate by the liver.(ABSTRACT TRUNCATED AT 250 WORDS)

Liver Blood Flow as a Major Determinant of the Clearance of Recombinant Human Tissue-Type Plasminogen Activator

1992 ◽  
Vol 67 (01) ◽  
pp. 083-087 ◽  
Author(s):  
A de Boer ◽  
C Kluft ◽  
J M Kroon ◽  
F J Kasper ◽  
H C Schoemaker ◽  
...  
Keyword(s):  
Blood Flow ◽  
Rat Liver ◽  
Healthy Subjects ◽  
Liver Blood Flow ◽  
Major Determinant ◽  
Tissue Type ◽  
Perfused Rat Liver ◽  
Liver Model ◽  
Type Plasminogen Activator ◽  
Proportional Change

SummaryThe influence of changes in liver blood flow on the clearance of rt-PA was studied both in healthy subjects and in a perfused rat liver model. Liver blood flow in healthy subjects was documented indirectly by the clearance of indocyanine green (ICG). Exercise reduced liver blood flow on average by 57% with a 95% confidence interval (95% Cl) ranging from 51% to 62% (n = 5) and increased plasma levels of rt-PA activity (after an i. v. infusion of 18 mg of rt-PA over 120 min) by 119% (95% Cl, 58% - 203%) and rt-PA antigen by 91% (95% Cl, 30% - 140%). In the perfused rat liver model it was shown that halving or doubling of the physiological flow rate of a perfusate, containing rt-PA caused a proportional change in the clearance of rt-PA, while the extraction of rt-PA by the liver remained similar. In conclusion, liver blood flow is a major determinant of the clearance of rt-PA. This may have important implications for dosage of rt-PA in patients with myocardial infarction.

Ultrasound features of peripheral angiodistonic syndrome of the upper extremities in vibration disease

2020 ◽  
Vol 60 (11) ◽  
pp. 815-817
Author(s):  
Nadezhda I. Kuprina ◽  
Ekaterina V. Ulanovskaya ◽  
Olga A. Kochetova
Keyword(s):  
Blood Flow ◽  
Heart Defects ◽  
Peripheral Resistance ◽  
Resistance Index ◽  
Ulnar Artery ◽  
Upper Extremities ◽  
Disease Stage ◽  
Peripheral Blood Flow ◽  
Pronounced Increase ◽  
Vibration Disease

Introduction. Vibration disease (VD) is an example of the most common pathology due to the systematic exposure of the worker to intense vibration with sufficient work experience, the main manifestation of which is peripheral angiodystonic syndrome. The aim of study was to learn the features of peripheral blood flow in the arteries of the forearm in vibration disease using the ultrasound method. Materials and methods. The radial and ulnar arteries in patients with vibration disease were examined by ultrasound in B- and PW-mode. These materials present the results of an ultrasound assessment of the speed indicators of the main arteries of the forearm in vibration disease stages 1 and 2. The selection criteria for patients in the study ware the presence of pronounced clinical manifestations of angiodystonic syndrome in vibration disease, confirmed by instrumental research methods and data on the sanitary and hygienic characteristics of working conditions, the absence of cardiovascular chronic diseases (ischemic heart disease, heart defects, rhythm and conduction disturbances), rheumatic, oncological, infectious diseases, osteo-traumatic changes in the upper extremities. Results. The groups of patients with the established diagnosis of vibration disease of 1 and 2 degrees were studied. With vibration disease stage 1 a decrease in the pulse velocity of blood flow was observed in isolation on the ulnar artery and an increase in peripheral resistance (pulsation index and resistance index) in the radial and ulnar arteries symmetrically on both upper extremities. The second stage of vibration disease differed from the first by a more significant decrease in speed indicators both on the ulnar and radial arteries on both sides, symmetrically in combination with a more pronounced increase in peripheral resistance indicators on both main arteries of the forearm (pulsation index and resistance index). The revealed changes were determined with the same frequency in men and women. Conclusions. A significant decrease in speed indicators on the ulnar artery and an increase in peripheral resistance indicators are detected already at the initial stages of vibration disease. Thus, the method of ultrasound examination of the main arteries of the middle caliber of the upper extremities is currently the only available and objective method for examining the vascular system in vibration disease.

RATIONALIZATION FOR THE DIFFERENTIAL DIAGNOSIS OF OVARIAN CANCER AND CHRONIC SALPINGOOPHORITIS IN THE PARAMETERS OF DISINTEGRATION AND NETWORK MODELING CHANGES OF BLOOD FLOW IN UTERINE AND OVARIAN ARTERIES AND VEINS

2017 ◽  
Vol 63 (5) ◽  
pp. 766-769
Author(s):  
Nikolay Agarkov ◽  
Pavel Tkachenko ◽  
Dmitriy Kicha ◽  
Vitaliy Aksenov ◽  
Aleksandr Ivanov ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Blood Flow ◽  
Diagnostic Criteria ◽  
Peripheral Resistance ◽  
Resistance Index ◽  
Diagnostic Process ◽  
Venous Outflow ◽  
Flow Changes ◽  
Arteries And Veins ◽  
Selection Of

Analysis of ultrasonic blood flow changes in uterine and ovarian arteries and veins in 92 patients with ovarian cancer and 87 patients with chronic salpingoophoritis has allowed to identify the leading differential diagnostic criteria, which include minimum diastolic blood flow velocity, resistance index, while fast hyperemia, the index of venous outflow diastolic index and index of peripheral resistance. Based on a selection of leading differential diagnostic criteria for ovarian cancer and chronic salpingoophoritis developed a network model of differentiation of these groups of patients, streamlining the differential diagnostic process

Portal Blood Flow as Measured by the Doppler Shift Technique in Sheep Fed Chopped Forages

1975 ◽  
Vol 41 (2) ◽  
pp. 596-600 ◽  
Author(s):  
L. R. Prewitt ◽  
D. R. Jacobson ◽  
R. W. Hemken ◽  
R. H. Hatton
Keyword(s):  
Blood Flow ◽  
Doppler Shift ◽  
Portal Blood Flow ◽  
Portal Blood ◽  
Shift Technique
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