Detection of early central circulatory transits in patients with cirrhosis by gamma variate fit of indicator dilution profiles

2005 ◽  
Vol 288 (4) ◽  
pp. G677-G684 ◽  
Author(s):  
Jens H. Henriksen ◽  
Søren Møller ◽  
Stefan Fuglsang ◽  
Flemming Bendtsen
Keyword(s):  
Cardiac Output ◽  
Blood Volume ◽  
Indicator Dilution ◽  
Arterial Oxygen ◽  
Dilution Method ◽  
Gamma Variate ◽  
Arterial Blood ◽  
Flow Circulation ◽  
Cirrhotic Patients

Patients with cirrhosis have hyperdynamic circulation with abnormally distributed blood volume and widespread arteriovenous communications. We aimed to detect possible very early (i.e., before 4 s) and early (i.e., after 4 s) central circulatory transits and their potential influence on determination of central and arterial blood volume (CBV). Thirty-six cirrhotic patients and nineteen controls without liver disease undergoing hemodynamic catheterization were given central bolus injections of albumin with different labels. Exponential and gamma variate fits were applied to the indicator dilution curves, and the relations between flow, circulation times, and volumes were established according to kinetic principles. No significant very early central circulatory transits were identified. In contrast, early (i.e., 4 s to maximal) transits corresponding to a mean of 5.1% (vs. 0.8% in controls; P < 0.005) of cardiac output (equivalent to 0.36 vs. 0.05 l/min; P < 0.01) were found in cirrhotic patients. These early transits averaged 7.7 vs. 12.7 and 17.2 s of ordinary central transits of cirrhotic patients and controls, respectively ( P < 0.001). Early transits were directly correlated to the alveolar-arterial oxygen difference in the cirrhotic patients ( r = 0.46, P < 0.01) but not in controls ( r = 0.04; not significant). There was good agreement between the CBV determined by the conventional indicator dilution method and that determined by separation of early and ordinary transits by the gamma variate fit method (1.51 vs. 1.53 liter; not significant). In conclusion, no very early central circulatory transits were identified in cirrhotic patients. A significant part of the cardiac output undergoes an early transit, probably through pulmonary shunts or areas with low ventilation-perfusion ratios in cirrhotic patients. Composite determination of CBV by the gamma variate fit method is in close agreement with established kinetic methods. The study provides further evidence of abnormal central circulation in cirrhosis.

Determination of central blood volume. Comparison of Stewart-Hamilton method with direct measurements in dogs

1959 ◽  
Vol 196 (3) ◽  
pp. 499-501 ◽  
Author(s):  
Robert C. Schlant ◽  
Paul Novack ◽  
William L. Kraus ◽  
Charles B. Moore ◽  
Florence W. Haynes ◽  
...  
Keyword(s):  
Cardiac Output ◽  
Blood Volume ◽  
Transit Time ◽  
Mean Transit Time ◽  
Total Radioactivity ◽  
Indicator Dilution ◽  
Dilution Method ◽  
Central Blood Volume ◽  
Volume Comparison ◽  
Direct Measurements

Central blood volume (cardiac output times mean transit time) from right atrium to ascending aorta was determined by the indicator-dilution method in 22 open-chested dogs which had previously had their red blood cells tagged with Cr51. The actual amount of blood in the heart and lungs was calculated from the total radioactivity in the blended homogenate of these organs. The two measurements of central blood volume correlated well ( r = +.88), the indicator-dilution volumes averaging 12% greater. The discrepancy between measurements is probably related to the pulmonary circuit having a lower hematocrit than the large vessels. The results substantiate the use of the Stewart-Hamilton formula (cardiac output times mean transit time) to measure central blood volume.

Measurement of Cardiac Output in Rats by 125I Dilution

1971 ◽  
Vol 49 (12) ◽  
pp. 1019-1022 ◽  
Author(s):  
R. T. Cotton ◽  
F. L. Mugashe ◽  
B. L. Gallie ◽  
H. Chan ◽  
I. H. Koven ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Cardiac Output ◽  
Indicator Dilution ◽  
Male Rats ◽  
Dilution Method ◽  
Small Animals ◽  
Arterial Blood ◽  
Single Animal ◽  
The Mean ◽  
Wistar Male Rats

A simple, rapid, indicator-dilution method of estimating cardiac output in small animals using 125I human serum albumin has been developed. The variation of repeat determinations in a single animal was ±10%. The cardiac output in normotensive 250–350 g Wistar male rats was 217 ± 28 (±S.D.) ml/kg min−1. These results agree with others derived by more tedious methods. After the mean arterial blood pressure was reduced to 50 mm Hg for 60 min by hemorrhage the cardiac output declined to 104 ± 40 ml/kg min−1. With this method it is possible to repeat determinations of cardiac output during shock.

scholarly journals Interrelationship between cardiac output and vascular resistance as determinants of effective arterial blood volume in cirrhotic patients

1985 ◽  
Vol 28 (2) ◽  
pp. 206-211 ◽  
Author(s):  
Michael D. Shapiro ◽  
Kathleen M. Nicholls ◽  
Bertron M. Groves ◽  
Rudiger Kluge ◽  
Hsaio-Min Chung ◽  
...  
Keyword(s):  
Cardiac Output ◽  
Blood Volume ◽  
Vascular Resistance ◽  
Arterial Blood ◽  
Cirrhotic Patients ◽  
Arterial Blood Volume

Measurement of cardiac output in adult and newborn animals by ascorbic acid dilution

1984 ◽  
Vol 246 (5) ◽  
pp. H733-H738
Author(s):  
J. K. Smallwood ◽  
K. A. Haselby ◽  
R. R. Paradise
Keyword(s):  
Ascorbic Acid ◽  
Cardiac Output ◽  
Venous Catheter ◽  
Indicator Dilution ◽  
Dilution Method ◽  
Dilution Curve ◽  
Indicator Dilution Curve ◽  
Arterial Blood ◽  
On Line ◽  
Replicate Measurements

We have developed an ascorbic acid-dilution method for measuring cardiac output which requires minimal blood withdrawal. Ascorbate is injected into a central venous catheter. The indicator-dilution curve is obtained by drawing blood from an arterial catheter through an amperometric cell at 0.96 ml/min for 35 s. The current is measured by a picoammeter . A calibration curve is obtained in 15 s prior to each indicator-dilution curve. An on-line digital computer measures the curve areas and calculates the cardiac output. Cardiac outputs of heparinized dogs anesthetized with pentobarbital and halothane measured by this method (AA) compared closely to cardiac outputs measured by the dye-dilution method (CG) (AA = 0.96 CG + 20 ml/min, r = 0.98). Both the cardiac output and the arterial blood pressure remained stable during replicate measurements of the cardiac output of 1-day-old piglets. This system allows cardiac output determinations of neonatal subjects without excessive blood removal and, with further development, should be practical in human neonates.

Supine exercise restores arterial blood pressure and skin blood flow despite dehydration and hyperthermia

1999 ◽  
Vol 277 (2) ◽  
pp. H576-H583 ◽  
Author(s):  
José González-Alonso ◽  
Ricardo Mora-Rodríguez ◽  
Edward F. Coyle
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiac Output ◽  
Arterial Blood Pressure ◽  
Blood Volume ◽  
Plasma Catecholamines ◽  
Central Blood Volume ◽  
Vascular Conductance ◽  
Arterial Blood ◽  
Cutaneous Vascular Conductance

We determined whether the deleterious effects of dehydration and hyperthermia on cardiovascular function during upright exercise were attenuated by elevating central blood volume with supine exercise. Seven trained men [maximal oxygen consumption (V˙o 2 max) 4.7 ± 0.4 l/min (mean ± SE)] cycled for 30 min in the heat (35°C) in the upright and in the supine positions (V˙o 2 2.93 ± 0.27 l/min) while maintaining euhydration by fluid ingestion or while being dehydrated by 5% of body weight after 2 h of upright exercise. When subjects were euhydrated, esophageal temperature (Tes) was 37.8–38.0°C in both body postures. Dehydration caused equal hyperthermia during both upright and supine exercise (Tes = 38.7–38.8°C). During upright exercise, dehydration lowered stroke volume (SV), cardiac output, mean arterial pressure (MAP), and cutaneous vascular conductance and increased heart rate and plasma catecholamines [30 ± 6 ml, 3.0 ± 0.7 l/min, 6 ± 2 mmHg, 22 ± 8%, 14 ± 2 beats/min, and 50–96%, respectively; all P < 0.05]. In contrast, during supine exercise, dehydration did not cause significant alterations in MAP, cutaneous vascular conductance, or plasma catecholamines. Furthermore, supine versus upright exercise attenuated the increases in heart rate (7 ± 2 vs. 9 ± 1%) and the reductions in SV (13 ± 4 vs. 21 ± 3%) and cardiac output (8 ± 3 vs. 14 ± 3%) (all P< 0.05). These results suggest that the decline in cutaneous vascular conductance and the increase in plasma norepinephrine concentration, independent of hyperthermia, are associated with a reduction in central blood volume and a lower arterial blood pressure.

Cardiovascular actions of histamine and potassium

1959 ◽  
Vol 197 (5) ◽  
pp. 1005-1007 ◽  
Author(s):  
Calvin Hanna ◽  
Patricia B. McHugo ◽  
William H. MacMillan
Keyword(s):  
Cardiac Output ◽  
Central Venous Pressure ◽  
Potassium Chloride ◽  
Venous Pressure ◽  
Plasma Potassium ◽  
Dilution Method ◽  
Cardiac Rate ◽  
Central Venous ◽  
Arterial Blood ◽  
Cardiovascular Actions

The cardiovascular actions of intravenous histamine, in doses from 2.5 to 20 µg/kg of the free base, were studied in the pentobarbitalized dog using the dye dilution method. With the small dose there was a consistent but small initial increase in cardiac output and with the larger doses there was a biphasic change in output. Cardiac rate, central venous pressure, central blood volume, hematocrit and the mean circulation time were essentially unchanged. Infusions of histamine and of potassium chloride at the rate of 1 µg and 1 mg/kg/min., respectively, moderately increased the cardiac output. Potassium chloride had no effect on the arterial blood pressure, cardiac rate and central venous pressure. Both the infusion of potassium chloride and injection of histamine produced a comparable elevation of the plasma potassium. It is possible that the actions of histamine to increase the plasma potassium contribute to the cardiovascular actions of this amine, especially on the cardiac output.

Effects of serotonin on pulmonary blood volume in the dog

1962 ◽  
Vol 202 (5) ◽  
pp. 957-960 ◽  
Author(s):  
Charles J. McGaff ◽  
William R. Milnor
Keyword(s):  
Cardiac Output ◽  
Blood Volume ◽  
Vascular Resistance ◽  
Transit Time ◽  
Mean Transit Time ◽  
Dilution Method ◽  
Continuous Intravenous Infusion ◽  
Pulmonary Blood Volume ◽  
Control Value ◽  
Vascular Bed

Changes in pulmonary blood volume produced by continuous intravenous infusion of serotonin (5-hydroxytryptamine) were measured in 16 experiments on ten dogs. Pulmonary mean transit time was measured by the dye dilution method, using consecutive injections into pulmonary artery and left atrium; pulmonary blood volume was calculated by multiplying this mean transit time by the cardiac output. Serotonin lowered pulmonary blood volume by an average of 2.9 ml/kg, or 26% of the control value ( P <0.001). Pulmonary vascular resistance increased 94 ru (resistance units) kg, and systemic vascular resistance fell 294 ru kg, effects similar to those reported by other investigators. The magnitude of the decrease in pulmonary blood volume indicates that a relatively large part of the pulmonary vascular bed is constricted by serotonin, and provides an example of shifting of blood from pulmonic to systemic circuits by reciprocal changes in the distensibility of these beds.

A small, lightweight precordial counter for determination of cardiac output

1965 ◽  
Vol 20 (6) ◽  
pp. 1365-1366 ◽  
Author(s):  
Ralph J. Gorten
Keyword(s):  
Cardiac Output ◽  
Scintillation Detector ◽  
Treadmill Exercise ◽  
Bicycle Ergometer ◽  
Indicator Dilution ◽  
Energy Gamma ◽  
Lead Shielding ◽  
Thin Crystal ◽  
Dilution Curves

A compact, lightweight scintillation detector which can be firmly attached to the anterior chest was fabricated in order to better adapt the isotope-precordial counting technic for measurements of cardiac output during exercise. In this manner useful indicator-dilution curves can be obtained without arterial puncture at light-to-heavy levels of bicycle ergometer or treadmill exercise. The use of a thin crystal and the omission of lead shielding and collimation of the detector is possible with a soft-energy gamma-emitting indicator of blood flow such as iodinated (I125) albumin. cardiac output during exercise; lightweight precordial scintillation detector; iodione 125; isotope-precordial counting technic Submitted on May 28, 1965

An improved procedure for determination of cardiac output by a conductivity method

1960 ◽  
Vol 15 (6) ◽  
pp. 1062-1064 ◽  
Author(s):  
Edward J. Hershgold ◽  
Sheldon H. Steiner ◽  
Leo A. Sapirstein
Keyword(s):  
Cardiac Output ◽  
Cardiac Cycle ◽  
Base Line ◽  
Dilution Technique ◽  
Conductivity Method ◽  
Blood Conductivity ◽  
Arterial Blood ◽  
Dog Plasma ◽  
Synthetic Solution

The applicability of the hematocrit dilution technique employing arterial blood conductivity changes to the determination of the cardiac output has been extended by a) electronic damping of the detecting circuits, which permits greater amplification of the signal without increasing the variability of the base line that occurs during each cardiac cycle, and by b) development of a solution isoosmolar and isoconductive with plasma that substitutes for autogenous plasma in the procedure. The preparation of the synthetic solution is described. It is shown that this solution gives results indistinguishable from those obtained with plasma. Values are given for the conductivity and osmolarity of dog plasma. Submitted on December 3, 1959

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