Spleen Blood Flow and Splanchnic Haemodynamics in Blood Dyscrasia and other Splenomegalies

1970 ◽  
Vol 38 (1) ◽  
pp. 73-84 ◽  
Author(s):  
L. M. Blendis ◽  
D. C. Banks ◽  
C. Ramboer ◽  
R. Williams
Keyword(s):  
Blood Flow ◽  
Liver Blood Flow ◽  
Portal Tract ◽  
Reticuloendothelial System ◽  
Blood Dyscrasia ◽  
Oesophageal Varices ◽  
Spleen Size ◽  
Blood Flows ◽  
Hepatic Histology ◽  
Wedged Hepatic Vein Pressure

1. Splenic blood flow and splanchnic haemodynamics have been studied in twenty patients with splenomegaly due to blood dyscrasia or diseases involving the reticuloendothelial system. Thirteen of these patients had portal hypertension, three had abdominal collaterals on arteriovenography and one oesophageal varices. 2. Total spleen blood flow was increased in all with values up to 1550 ml/min, and associated with this liver blood flows increased up to 2·61 1 min−1 m−2. In four patients the cardiac output was raised. 3. In five patients a raised wedged hepatic vein pressure was found which was solely related to the increase in liver blood flow, but in two others, in whom hepatic histology was abnormal, there was also an increase in postsinusoidal resistance. Nine patients had a raised hepatic pre-sinusoidal resistance. This was related to a greatly increased liver blood flow with portal tract fibrosis and cellular infiltration as possible additional factors. 4. The haemodynamic findings in these patients were similar to those found previously in patients with tropical splenomegaly. In both groups spleen blood flow in ml 100 g−1 min−1 was inversely proportional to spleen size. There were similar increases in total spleen and liver blood flows and in the percentage of patients with an increased pre-sinusoidal resistance. In contrast, in cirrhosis there was no inverse relationship between flow in 1 100 g−1 min−1, and of spleen size, and for the degree of splenomegaly total spleen blood flow was relatively greater.

The effect of normothermic cardiopulmonary bypass on hepatic blood flow in the dog

Perfusion ◽  
1986 ◽  
Vol 1 (4) ◽  
pp. 245-253 ◽  
Author(s):  
RT Mathie ◽  
JB Desai ◽  
KM Taylor
Keyword(s):  
Blood Flow ◽  
Cardiopulmonary Bypass ◽  
Vascular Resistance ◽  
Flow Rate ◽  
Hepatic Blood Flow ◽  
Liver Blood Flow ◽  
Relative Reduction ◽  
Blood Flows ◽  
Pump Flow ◽  
Pump Flow Rate

Hepatic blood flow was investigated in two groups of eight anaesthetized dogs during and after one hour of either pulsatile or non-pulsatile cardiopulmonary bypass (CPB). Mean perfusion pressure was maintained at 60 mmHg. Hepatic arterial (HA) and portal venous (PV) blood flows were measured using electromagnetic flow probes, and hepatic O 2 consumption determined. The results demonstrate that: (a) pulsatile CPB reduces peripheral vascular resistance during and after perfusion, and more effectively preserves pump flow rate and cardiac output than non-pulsatile CPB; (b) total liver blood flow is sustained more effectively by pulsatile CPB than by non-pulsatile CPB due to relative preservation of both HA and PV flows; (c) hepatic O2 consumption is only marginally better preserved during and after pulsatile CPB than with non-pulsatile perfusion. We conclude that: (a) pulsatile CPB tends to maintain hepatic blood flow through a relative reduction in HA vascular resistance and an improvement in PV flow produced passively by a greater pump flow rate; (b) pulsatile CPB less effectively benefits hepatic O2 consumption because of poor O2 uptake from the hepatic PV blood supply.

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.

Effects of liver blood flow on hepatic uptake kinetics of galactose in anesthetized cats: parallel tube model

1987 ◽  
Vol 65 (6) ◽  
pp. 1193-1199 ◽  
Author(s):  
C. V. Greenway ◽  
F. J. Burczynski
Keyword(s):  
Blood Flow ◽  
Steady State ◽  
Hepatic Blood Flow ◽  
Venous Blood ◽  
Liver Blood Flow ◽  
Control Flow ◽  
Tube Model ◽  
Blood Flows ◽  
Parallel Tube ◽  
Parallel Tube Model

Hepatic galactose uptake in cats anesthetized with pentobarbital was determined during (i) steady-state infusions at several doses, (ii) rapidly increasing infusion rates at different blood flows, and (iii) prolonged infusion of a single dose at different blood flows. The hepatic venous long-circuit technique was used to allow frequent sampling of arterial, portal, and hepatic venous blood without depletion of the animal's blood volume and to allow measurement and alteration of total hepatic blood flow. Uptake was shown to follow Michaelis–Menten kinetics and was consistent with the "parallel tube model." The kinetic parameters Vmax and Kmax could be determined under steady-state and nonsteady-state conditions and were independent of hepatic blood flow over the range 60–150% of control flow. Mean Vmax was 80 μmol/(min∙100 g liver) and mean Km was 215 μM. Vmax declined by 50% when flow was reduced to half normal. It is concluded that the parallel tube model can be used to describe and predict hepatic galactose kinetics in anesthetized cats, although other models may fit the data equally well.

Oxygen consumption by the gastrointestinal tract and liver in conscious newborn lambs

1981 ◽  
Vol 240 (4) ◽  
pp. G297-G304 ◽  
Author(s):  
D. I. Edelstone ◽  
I. R. Holzman
Keyword(s):  
Blood Flow ◽  
Gastrointestinal Tract ◽  
Liver Blood Flow ◽  
Whole Body ◽  
Fasting State ◽  
Newborn Animal ◽  
Blood Flows ◽  
O2 Extraction ◽  
Neonatal Liver ◽  
O2 Delivery

We determined blood flow to and O2 consumption (VO2) by the gastrointestinal tract (GI) and liver and also measured cardiac output and whole-body VO2 in nine chronically catheterized unanesthetized lambs (7-16 days of age). Blood flows were calculated with the radionuclide-labeled microsphere technique, and blood O2 contents were measured with an O2 content analyzer. During the fasting state, GI blood flow was 58 +/- 4 (means +/- SE) ml.min-1.kg body wt-1; GI VO2 was 1.4 +/- 0.1 ml O2.min-1.kg-1. Neonatal GI VO2 was linearly related to both GI blood flow and O2 delivery (DO2). GI O2 extraction [(VO2/DO2).100] averaged 28% and did not vary with blood flow or DO2. Liver blood flow was 73 +/- 4 ml.min-1.kg-1 (271 +/- 23 ml.min-1.100 g liver-1), and liver VO2 was 2.0 +/- 0.1 ml O2.min-1.kg-1 (7.3 +/- 0.5 ml O2.min-1.100 g-1). Hepatic O2 extraction varied from 18 to 81% . VO2 by the neonatal liver did not correlate with liver blood flow or DO2. Hepatic O2 extraction, however, was inversely related to liver DO2. Our data indicate that the gastrointestinal tract and liver of the unanesthetized newborn animal exhibit O2 demands 1.5-3 times those reported in the adult. The neonatal gastrointestinal tract meets its O2 demands with a comparatively large blood flow and O2 delivery, whereas the neonatal liver provides for its O2 requirements by varying its O2 extraction.

scholarly journals Cardiopulmonary values and organ blood flows before and during heat stress: data in nine subjects at rest in the upright position

2021 ◽  
Author(s):  
Pierre Brochu ◽  
Jessie Ménard ◽  
Axelle Marchand ◽  
Sami Haddad
Keyword(s):  
Blood Flow ◽  
Heat Stress ◽  
Liver Blood Flow ◽  
Pbpk Modeling ◽  
Healthy Male ◽  
Blood Flows ◽  
Complete Set ◽  
Excretion Rates ◽  
The Impact ◽  
Kinetics Of

Physiological changes associated with thermoregulation can influence the kinetics of chemicals in the human body, such as alveolar ventilation (VA) and redistribution of blood flow to organs. In this study, the influence of heat stress on various physiological parameters was evaluated in nine male volunteers during sessions of exposure to wet blub globe temperatures (WBGT) of 21, 25 and 30°C for four hours. Skin and core temperatures and more than twenty cardiopulmonary parameters were measured. Liver, kidneys, brain, skin and muscles blood flows were also determined based on published measurements. Results show that most subjects (8 out of 9) have been affected by the inhalation of hot and dry air at the WBGT of 30°C. High respiratory rates, superficial tidal volumes and low VA values were notably observed. The skin blood flow has increased by 2.16-fold, whereas the renal blood flow and liver blood flow have decreased by about by 11 and 18% respectively. A complete set of key cardiopulmonary parameters in healthy male adults before and during heat stress was generated for use in PBPK modeling. A toxicokinetic studies are ongoing to evaluate the impact of heat stress on the absorption, biotransformation and excretion rates of volatile xenobiotics.

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.

COMPARISON OF ANTIHYPERTENSIVE EFFECT OF MOXONIDINE VERSUS CLONIDINE IN RENAL FAILURE PATIENTS.

2018 ◽  
Vol 6 (9) ◽  
Author(s):  
DR.MATHEW GEORGE ◽  
DR.LINCY JOSEPH ◽  
MRS.DEEPTHI MATHEW ◽  
ALISHA MARIA SHAJI ◽  
BIJI JOSEPH ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Renal Failure ◽  
Blood Flow ◽  
Blood Vessel ◽  
Blood Vessels ◽  
High Blood Pressure ◽  
Antihypertensive Effect ◽  
The Body ◽  
Ability To Work ◽  
Blood Flows

Blood pressure is the force of blood pushing against blood vessel walls as the heart pumps out blood, and high blood pressure, also called hypertension, is an increase in the amount of force that blood places on blood vessels as it moves through the body. Factors that can increase this force include higher blood volume due to extra fluid in the blood and blood vessels that are narrow, stiff, or clogged(1). High blood pressure can damage blood vessels in the kidneys, reducing their ability to work properly. When the force of blood flow is high, blood vessels stretch so blood flows more easily. Eventually, this stretching scars and weakens blood vessels throughout the body, including those in the kidneys.

Myocardial blood flow determined with krypton 85 in unanesthetized dogs

1962 ◽  
Vol 203 (1) ◽  
pp. 122-124 ◽  
Author(s):  
J. A. Herd ◽  
M. Hollenberg ◽  
G. D. Thorburn ◽  
H. H. Kopald ◽  
A. C. Barger
Keyword(s):  
Blood Flow ◽  
Coronary Artery ◽  
Myocardial Blood Flow ◽  
Exponential Function ◽  
Scintillation Detector ◽  
Left Ventricular ◽  
Blood Flows ◽  
Single Exponential Function ◽  
Single Exponential ◽  
Rapid Measurements

Serial, rapid measurements of left ventricular myocardial blood flow in trained, unanesthetized dogs have been made by injecting krypton 85 through chronically implanted coronary artery catheters and counting with an external scintillation detector. Precordial radioactivity declined as a single exponential function during the first 2 min after injection, suggesting a single rate of myocardial blood flow. Simultaneous estimations with Kr85 and blood flowmeters in acute experiments established the accuracy and reproducibility of the technique. Myocardial blood flows between 40 and 55 ml/100 g/min were observed repeatedly in three well-trained, unanesthetized dogs in the basal state.

scholarly journals Randomized Trial of Oxygen Saturation Targets during and after Resuscitation and Reversal of Ductal Flow in an Ovine Model of Meconium Aspiration and Pulmonary Hypertension

Children ◽  
2021 ◽  
Vol 8 (7) ◽  
pp. 594
Author(s):  
Amy L. Lesneski ◽  
Payam Vali ◽  
Morgan E. Hardie ◽  
Satyan Lakshminrusimha ◽  
Deepika Sankaran
Keyword(s):  
Blood Flow ◽  
Pulmonary Hypertension ◽  
Oxygen Saturation ◽  
Ductus Arteriosus ◽  
Neonatal Resuscitation ◽  
Meconium Aspiration Syndrome ◽  
Ovine Model ◽  
Neurodevelopmental Outcomes ◽  
Meconium Aspiration ◽  
Blood Flows

Neonatal resuscitation (NRP) guidelines suggest targeting 85–95% preductal SpO2 by 10 min after birth. Optimal oxygen saturation (SpO2) targets during resuscitation and in the post-resuscitation management of neonatal meconium aspiration syndrome (MAS) with persistent pulmonary hypertension (PPHN) remains uncertain. Our objective was to compare the time to reversal of ductal flow from fetal pattern (right-to-left), to left-to-right, and to evaluate pulmonary (QPA), carotid (QCA)and ductal (QDA) blood flows between standard (85–94%) and high (95–99%) SpO2 targets during and after resuscitation. Twelve lambs asphyxiated by endotracheal meconium instillation and cord occlusion to induce MAS and PPHN were resuscitated per NRP guidelines and were randomized to either standard (85–94%) or high (95–99%) SpO2 targets. Out of twelve lambs with MAS and PPHN, six each were randomized to standard and high SpO2 targets. Median [interquartile range] time to change in direction of blood flow across the ductus arteriosus from right-to-left, to left-to-right was significantly shorter with high SpO2 target (7.4 (4.4–10.8) min) compared to standard SpO2 target (31.5 (21–66.2) min, p = 0.03). QPA was significantly higher during the first 10 min after birth with higher SpO2 target. At 60 min after birth, the QPA, QCA and QDA were not different between the groups. To conclude, targeting SpO2 of 95–99% during and after resuscitation may hasten reversal of ductal flow in lambs with MAS and PPHN and transiently increase QPA but no differences were observed at 60 min. Clinical studies comparing low and high SpO2 targets assessing hemodynamics and neurodevelopmental outcomes are warranted.

Sign in / Sign up

Export Citation Format

Share Document