Effects of Dobutamine on the Relationship between Oxygen Consumption and Delivery in Healthy Volunteers: Comparison with Sodium Nitroprusside

1996 ◽  
Vol 90 (2) ◽  
pp. 105-111 ◽  
Author(s):  
Daniel De Backer ◽  
Jacques Berre ◽  
Jean Jacques Moraine ◽  
Christian Melot ◽  
Jacques Vanfraechem ◽  
...  
Keyword(s):  
Blood Flow ◽  
Oxygen Consumption ◽  
Healthy Volunteers ◽  
Sodium Nitroprusside ◽  
Repeated Measurements ◽  
Therapeutic Interventions ◽  
Adrenergic Agents ◽  
Electrical Bioimpedance ◽  
Oxygen Requirements ◽  
The Relationship

1. Dobutamine has been used to study the relationship between oxygen consumption (VO2) and oxygen delivery (DO2) in critically ill patients, but this has led to concerns that it could consistently increase VO2 in all patients. Although a direct thermogenic effect of the catecholamine has been primarily implicated in this increase in VO2, an increase in blood flow may contribute significantly by increasing the oxygen requirements of the heart and other organs such as the kidney and the liver. If this mechanism is predominant, it should also be observed when blood flow increases during the infusion of non-adrenergic agents. To separate the two mechanisms, we compared the effects of dobutamine with those of sodium nitroprusside on VO2/DO2 relationships in healthy volunteers. 2. Eight healthy volunteers received infusions of dobutamine at doses of 2, 4 and 6 μg min−1 kg−1 and nitroprusside at doses of 0.5, 1 and 2 μg min−1 kg−1 in an alternate order. 3. VO2 was determined by indirect calorimetry and cardiac output by electrical bioimpedance. Data were analysed by analysis of variance for repeated measurements and individual VO2/DO2 slopes were determined by linear regression. 4. VO2 increased more with dobutamine than with nitroprusside (from 138 ± 14 to 149 ± 20 ml min−1 m−2, P < 0.001, and from 131 ± 14 to 138 ± 17 ml min−1 m−2, P < 0.001, respectively). However, DO2 also increased more with dobutamine than with nitroprusside (from 531 ± 186 to 702 ± 274 ml min−1 m−2, P < 0.001, and from 523 ± 107 to 610 ± 122 ml min−1 m−2, P < 0.001, respectively). Individual VO2/DO2 slopes were similar with dobutamine and nitroprusside (6.5 ± 3.5 compared with 7.1 ± 4.6%, P not significant). 5. At the doses used, DO2 and VO2 increased more with dobutamine than with nitroprusside in healthy volunteers. However, the VO2/DO2 slopes were similar for both substances. Thus, an increase in VO2 is not exclusively observed with catecholamines. Studies of the effects of therapeutic interventions on oxygen-derived variables should report not only changes in VO2 but also VO2/DO2 slopes.

Effect of solute-coupled volume absorption on oxygen consumption in cat ileum.

1979 ◽  
Vol 236 (2) ◽  
pp. E198
Author(s):  
J D Valleau ◽  
D N Granger ◽  
A E Taylor
Keyword(s):  
Blood Flow ◽  
Oxygen Consumption ◽  
Glucose Absorption ◽  
Tyrode Solution ◽  
Recovery Method ◽  
Volume Absorption ◽  
All Solutions ◽  
Volume Recovery ◽  
Oxygen Requirements ◽  
Increased Blood Flow

The effects of solute-coupled volume absorption on blood flow, oxygen consumption, and vascular resistance were analyzed in autoperfused segments of cat ileum. Intestinal absorption was stimulated by placing either Tyrode solution, Tyrode + glucose, or Tyrode + taurocholate into the ileal lumen. Net volume absorption rates (Jv,m) were determined using a volume recovery method. Oxygen consumption (VO2) increased during the absorption of all solutions. The absorption of Tyrode solution plus glucose caused the greatest increase in VO2, whereas Tyrode plus taurocholate resulted in the smallest increase. For Tyrode solution and Tyrode plus glucose absorption, the increased VO2 was due predominantly to an increased blood flow, whereas the increased VO2 with taurocholate resulted from an increased oxygen extraction. A linear relationship between the change in VO2 during transport and Jv,m was aquired for Tyrode solution, and Tyrode + glucose. The results indicate that the oxygen requirements of the absorbing intestine are dependent on both the rate of transport and the solutes being transported.

LV pressure-volume area and oxygen consumption: evaluation in intact dog by fast CT

1990 ◽  
Vol 258 (4) ◽  
pp. H1208-H1215
Author(s):  
N. Chung ◽  
X. Wu ◽  
K. R. Bailey ◽  
E. L. Ritman
Keyword(s):  
Blood Flow ◽  
Oxygen Consumption ◽  
Myocardial Blood Flow ◽  
Myocardial Oxygen Consumption ◽  
Systolic Pressure ◽  
Left Ventricular ◽  
Adrenergic Blockade ◽  
Ct Scanner ◽  
Beta Adrenergic ◽  
The Relationship

The relationship between left ventricular (LV) myocardial oxygen consumption (MVO2) and LV systolic pressure-volume area (PVA) was investigated in anesthetized closed-chest dogs with intact reflexes and subsequently with beta-adrenergic blockade, with or without simultaneous muscarinic blockade. LV chamber volumes were measured using a fast computerized tomography (CT) scanner (dynamic spatial reconstructor, DSR) at 33-ms intervals. Myocardial blood flow was measured from the DSR scans of aortic root angiograms. With intact reflexes, LV MVO2 (Y) related to PVA (X) values as Y = (4.28 +/- 1.81)X + (1.94 +/- 6.0) (n = 24) (mJ.g-1.cycle-1). With beta-adrenergic blockade, LV MVO2 (Y) related to PVA (X) value as Y = (4.24 +/- 1.03)X - (6.43 +/- 6.5), (n = 9) (mJ.g-1.cycle-1). With beta-adrenergic and muscarinic blockade, LV MVO2 (Y) related to PVA (X) value as Y = (2.84 +/- 1.72)X + (3.51 +/- 5.15), (n = 13) (mJ.g-1.cycle-1). The slopes of these regressions are higher than the slopes demonstrated by others in isolated ventricles but very similar to those demonstrated in open-chest dogs.

Oxygen requirements of the dyskinetic myocardial segment

1989 ◽  
Vol 257 (4) ◽  
pp. H1184-H1191 ◽  
Author(s):  
P. A. Gayheart ◽  
J. Vinten-Johansen ◽  
W. E. Johnston ◽  
T. O. Hester ◽  
A. R. Cordell
Keyword(s):  
Blood Flow ◽  
Oxygen Consumption ◽  
Coronary Arteries ◽  
Dose Response ◽  
Contractile Function ◽  
Myocardial Segment ◽  
Response Curves ◽  
Intracoronary Infusion ◽  
Oxygen Requirements ◽  
Measure Oxygen Consumption

Oxygen requirements of a noncontracting myocardial segment subjected to passive systolic stretch (dyskinesis) have not been well described. The purpose of this study was to measure oxygen consumption (MVO2) of a myocardial segment made dyskinetic by intracoronary infusion of lidocaine. In 12 anesthetized open-chest dogs, segmental shortening was measured sonomicrometrically in regions perfused by the left anterior descending (LAD) and circumflex (Cfx) coronary arteries. MVO2 was measured by arterial-venous oxygen content differences and transmural blood flow. Dose-response curves to intracoronary lidocaine showed that complete dyskinesis was achieved by a 0.25-mg/ml dose of lidocaine, whereas the Cfx region maintained a constant level of segmental shortening. MVO2 of the LAD segment was similar to that of the Cfx segment under control conditions. With lidocaine-induced dyskinesis, MVO2 in the arrested segment was reduced by 33% (P less than 0.05), despite the loss of contractile function. When bulging was prevented by ventricular unloading, MVO2 in the arrested segment decreased to 2.65 ml O2.min-1.100 g-1 (i.e., basal oxygen requirements). In conclusion, MVO2 in a pharmacologically arrested myocardial segment undergoing systolic bulging is paradoxically high relative to both basal requirements and MVO2 in the normally contracting segment.

Adenosine and coronary blood flow in conscious dogs during normal physiological stimuli

1982 ◽  
Vol 243 (4) ◽  
pp. H628-H633 ◽  
Author(s):  
A. N. Bacchus ◽  
S. W. Ely ◽  
R. M. Knabb ◽  
R. Rubio ◽  
R. M. Berne
Keyword(s):  
Blood Flow ◽  
Oxygen Consumption ◽  
Coronary Blood Flow ◽  
Myocardial Oxygen Consumption ◽  
Oxygen Supply ◽  
Physiological Mechanism ◽  
Oxygen Demand ◽  
The Relationship ◽  
Chronically Instrumented Dogs

The role of adenosine in matching myocardial oxygen supply to demand by regulating coronary blood flow has been the subject of intensive study. The present experiments were designed to determine the relationship among myocardial oxygen consumption, coronary blood flow, and adenosine production as estimated by pericardial adenosine accumulation under several physiological conditions in the same animal. Conscious chronically instrumented dogs were used to measure changes in coronary blood flow, myocardial oxygen consumption, and pericardial adenosine accumulation during two levels of treadmill exercise, excitement caused by loud noises, and feeding (the presentation and consumption of a meal). The results show significant increases in the adenosine production with all experimental procedures and significant linear correlations between myocardial oxygen consumption and coronary blood flow (r = 0.78), myocardial oxygen consumption and adenosine production (r = 0.73), and adenosine production and coronary blood flow (r = 0.88). These data show that increases in adenosine production by the normally oxygenated myocardium can be the physiological mechanism for matching oxygen supply to increased oxygen demand in the conscious dog.

The Effect of Tirilazad Mesylate (U74006F) on Cerebral Oxygen Consumption, and Reactivity of Cerebral Blood Flow to Carbon Dioxide in Healthy Volunteers

1993 ◽  
Vol 79 (4) ◽  
pp. 666-671 ◽  
Author(s):  
Karsten Skovgaard Olsen ◽  
Charlotte Videbaek ◽  
Niels Agerlin ◽  
Martin Kroll ◽  
Torben Boge-Rasmussen ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Oxygen Consumption ◽  
Healthy Volunteers ◽  
Cerebral Oxygen ◽  
Tirilazad Mesylate ◽  
Cerebral Oxygen Consumption

scholarly journals Sodium Nitroprusside–Enhanced Cardiopulmonary Resuscitation Improves Blood Flow by Pulmonary Vasodilation Leading to Higher Oxygen Requirements

2020 ◽  
Vol 5 (2) ◽  
pp. 183-192 ◽  
Author(s):  
Adrian Ripeckyj ◽  
Marinos Kosmopoulos ◽  
Kadambari Shekar ◽  
Claire Carlson ◽  
Rajat Kalra ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cardiopulmonary Resuscitation ◽  
Sodium Nitroprusside ◽  
Pulmonary Vasodilation ◽  
Oxygen Requirements

Blood oxygen requirements in resting crab (Carcinus maenas) 24 h after feeding

1999 ◽  
Vol 77 (5) ◽  
pp. 784-794 ◽  
Author(s):  
Alexia Legeay ◽  
Jean-Charles Massabuau
Keyword(s):  
Blood Flow ◽  
Oxygen Consumption ◽  
Flow Rate ◽  
Consumption Rate ◽  
Carcinus Maenas ◽  
Blood Flow Rate ◽  
Blood Oxygen ◽  
Partial Pressure Of Oxygen ◽  
Blood Ph ◽  
Oxygen Requirements

Numerous resting unfed water-breathers have a strategy of gas-exchange regulation that consists of setting the arterial partial pressure of oxygen (Pao2) at 1-3 kPa. This raises a question concerning the extent to which physiological functions are limited in this situation. To obtain insight into this problem, we studied the steady-state adaptation of the blood-oxygen transfer system in the crab Carcinus maenas during the doubling of the oxygen consumption rate, Mo2 (i.e., during the period of specific dynamic action of food (SDA)), that occurs 24 h after feeding. We showed that this increase in the oxygen consumption rate 24 h after a meal is not limited by a blood partial pressure of oxygen (Po2) as low as 0.8-1.5 kPa in either normoxia or hypoxia (Po2 of the inspired water = 4 kPa). In normoxia, adaptation of the oxygen-transport system, if any, consisted of a combined set of adaptations of small amplitude (in absolute value), rather than major changes in blood oxygenation status, blood flow rate, or oxygen affinity (although blood pH decreases). In hypoxia, the SDA was mainly associated with an increase in blood flow rate and blood pH, with no changes in blood lactate, urate, calcium, and haemocyanin concentrations. The results are discussed, in an environmental context, in terms of minimal oxygen requirements in water-breathers.

Effects of dipyridamole on myocardial adenosine and active hyperemia

1984 ◽  
Vol 247 (5) ◽  
pp. H804-H810 ◽  
Author(s):  
R. M. Knabb ◽  
J. M. Gidday ◽  
S. W. Ely ◽  
R. Rubio ◽  
R. M. Berne
Keyword(s):  
Blood Flow ◽  
Oxygen Consumption ◽  
Steady State ◽  
Myocardial Oxygen Consumption ◽  
Cardiac Work ◽  
Adenosine Release ◽  
Adenosine Uptake ◽  
Adenosine Concentration ◽  
The Relationship ◽  
Perfused Hearts

Dipyridamole, a vasodilator that potentiates the actions of exogenous adenosine, is known to inhibit cellular uptake of adenosine, but its effects on cellular adenosine release, and thus interstitial adenosine levels, are disputed. We used the accumulation of adenosine in pericardial infusates (PCI) as an index of interstitial adenosine concentration and observed the effects of dipyridamole on relationships among coronary blood flow (CBF), myocardial oxygen consumption (MVO2), and PCI adenosine concentrations during steady-state alterations of cardiac work. Dipyridamole increased CBF and PCI adenosine concentration without altering MVO2. The relationship between PCI adenosine and CBF was unaltered, supporting a cause and effect relationship between interstitial adenosine concentration and CBF. In addition, we determined that unlike previous studies in isolated perfused hearts the washout of adenosine by coronary plasma was unaffected by dipyridamole. The results support previous suggestions that, whereas dipyridamole inhibits adenosine uptake, it does not alter cellular adenosine release, and therefore interstitial adenosine levels are increased. The constant relationship between PCI adenosine and CBF supports hypotheses that attribute the hyperemias associated with increased cardiac work or with dipyridamole to increased interstitial adenosine.

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