Changes of Gas Concentrations in Blood and Water During Moderate Swimming Activity in Rainbow Trout

1967 ◽  
Vol 46 (2) ◽  
pp. 329-337
Author(s):  
E. DON STEVENS ◽  
D. J. RANDALL
Keyword(s):  
Cardiac Output ◽  
Rainbow Trout ◽  
Stroke Volume ◽  
Venous Blood ◽  
Recovery Period ◽  
Swimming Activity ◽  
Fick Principle ◽  
Arterial Blood ◽  
Partial Pressures ◽  
Volume Ventilation

1. Changes in partial pressures of O2 and CO2 in blood and water afferent and efferent to the gills are reported. These variables were measured before, during and after moderate swimming activity in rainbow trout. 2. Neither blood PCO2 nor water PO2, afferent or efferent to the gills, changed markedly before, during or after exercise. 3. Arterial blood was always more than 95% saturated with oxygen. Venous blood was 38% saturated, falling to a minimum of 28% during exercise. 4. PCO2 of arterial blood was 2.3 mm. Hg. Pco2 of venous blood increased from 5.7 to 8.0 mm. Hg during exercise and remained elevated throughout the recovery period. 5. Cardiac output (calculated using the Fick principle) stroke volume, ventilation volume and the volume of water pumped per breath all increase by a factor of between 4 and 5 during exercise. All tended to remain elevated for between 10 and 30 min. after exercise and then gradually decrease to pre-exercise levels.

Respiratory measurements of cardiac output: from elegant idea to useful test

2004 ◽  
Vol 96 (2) ◽  
pp. 428-437 ◽  
Author(s):  
Gabriel Laszlo
Keyword(s):  
Cardiac Output ◽  
Human Subjects ◽  
Venous Blood ◽  
The Body ◽  
Mixed Venous Blood ◽  
Indirect Determination ◽  
Arterial Blood ◽  
Pulmonary Capillary ◽  
Pulmonary Arterial ◽  
Mixed Venous

The measurement of cardiac output was first proposed by Fick, who published his equation in 1870. Fick's calculation called for the measurement of the contents of oxygen or CO2 in pulmonary arterial and systemic arterial blood. These values could not be determined directly in human subjects until the acceptance of cardiac catheterization as a clinical procedure in 1940. In the meanwhile, several attempts were made to perfect respiratory methods for the indirect determination of blood-gas contents by respiratory techniques that yielded estimates of the mixed venous and pulmonary capillary gas pressures. The immediate uptake of nonresident gases can be used in a similar way to calculate cardiac output, with the added advantage that they are absent from the mixed venous blood. The fact that these procedures are safe and relatively nonintrusive makes them attractive to physiologists, pharmacologists, and sports scientists as well as to clinicians concerned with the physiopathology of the heart and lung. This paper outlines the development of these techniques, with a discussion of some of the ways in which they stimulated research into the transport of gases in the body through the alveolar membrane.

Changes in Blood Pressure, Heart Rate and Breathing Rate During Moderate Swimming Activity in Rainbow Trout

1967 ◽  
Vol 46 (2) ◽  
pp. 307-315 ◽  
Author(s):  
E. DON STEVENS ◽  
D. J. RANDALL
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Rainbow Trout ◽  
Venous Blood ◽  
The Body ◽  
Swimming Activity ◽  
Breathing Rate ◽  
Blood Pressures ◽  
Ventral Aorta ◽  
Pressure Changes

1. Changes in blood pressure in the dorsal aorta, ventral aorta and subintestinal vein, as well as changes in heart rate and breathing rate during moderate swimming activity in the rainbow trout are reported. 2. Blood pressures both afferent and efferent to the gills increased during swimming and then returned to normal levels within 30 min. after exercise. 3. Venous blood pressure was characterized by periodic increases during swimming. The pressure changes were not in phase with the body movements. 4. Although total venous return to the heart increased during swimming, a decreased blood flow was recorded in the subintestinal vein. 5. Heart rate and breathing rate increased during swimming and then decreased when swimming ceased. 6. Some possible mechanisms regulating heart and breathing rates are discussed.

Estimation of ventilation-perfusion inequality by inert gas elimination without arterial sampling

1985 ◽  
Vol 59 (2) ◽  
pp. 376-383 ◽  
Author(s):  
P. D. Wagner ◽  
C. M. Smith ◽  
N. J. Davies ◽  
R. D. McEvoy ◽  
G. E. Gale
Keyword(s):  
Cardiac Output ◽  
Venous Blood ◽  
Inert Gas ◽  
Chronic Obstructive ◽  
Obstructive Pulmonary Disease ◽  
Arterial Access ◽  
Arterial Blood ◽  
Potential Applications ◽  
Clinical Interest ◽  
Mixed Venous

Estimation of ventilation-perfusion (VA/Q) inequality by the multiple inert gas elimination technique requires knowledge of arterial, mixed venous, and mixed expired concentrations of six gases. Until now, arterial concentrations have been directly measured and mixed venous levels either measured or calculated by mass balance if cardiac output was known. Because potential applications of the method involve measurements over several days, we wished to determine whether inert gas levels in peripheral venous blood ever reached those in arterial blood, thus providing an essentially noninvasive approach to measuring VA/Q mismatch that could be frequently repeated. In 10 outpatients with chronic obstructive pulmonary disease, we compared radial artery (Pa) and peripheral vein (Pven) levels of the six gases over a 90-min period of infusion of the gases into a contralateral forearm vein. We found Pven reached 90% of Pa by approximately 50 min and 95% of Pa by 90 min. More importantly, the coefficient of variation at 50 min was approximately 10% and at 90 min 5%, demonstrating acceptable intersubject agreement by 90 min. Since cardiac output is not available without arterial access, we also examined the consequences of assuming values for this variable in calculating mixed venous levels. We conclude that VA/Q features of considerable clinical interest can be reliably identified by this essentially noninvasive approach under resting conditions stable over a period of 1.5 h.

Breathing through an inspiratory threshold device improves stroke volume during central hypovolemia in humans

2008 ◽  
Vol 104 (5) ◽  
pp. 1402-1409 ◽  
Author(s):  
Kathy L. Ryan ◽  
William H. Cooke ◽  
Caroline A. Rickards ◽  
Keith G. Lurie ◽  
Victor A. Convertino
Keyword(s):  
Cardiac Output ◽  
Arterial Pressure ◽  
Stroke Volume ◽  
Lower Body Negative Pressure ◽  
Systolic Arterial Pressure ◽  
Intrathoracic Pressure ◽  
Subsequent Increase ◽  
Arterial Blood ◽  
Threshold Device ◽  
Inspiratory Resistance

Inspiratory resistance induced by breathing through an impedance threshold device (ITD) reduces intrathoracic pressure and increases stroke volume (SV) in supine normovolemic humans. We hypothesized that breathing through an ITD would also be associated with a protection of SV and a subsequent increase in the tolerance to progressive central hypovolemia. Eight volunteers (5 men, 3 women) were instrumented to record ECG and beat-by-beat arterial pressure and SV (Finometer). Tolerance to progressive lower body negative pressure (LBNP) was assessed while subjects breathed against either 0 (sham ITD) or −7 cmH2O inspiratory resistance (active ITD); experiments were performed on separate days. Because the active ITD increased LBNP tolerance time from 2,014 ± 106 to 2,259 ± 138 s ( P = 0.006), data were analyzed (time and frequency domains) under both conditions at the time at which cardiovascular collapse occurred during the sham experiment to determine the mechanisms underlying this protective effect. At this time point, arterial blood pressure, SV, and cardiac output were higher ( P ≤ 0.005) when breathing on the active ITD rather than the sham ITD, whereas indirect indicators of autonomic activity (low- and high-frequency oscillations of the R-to-R interval) were not altered. ITD breathing did not alter the transfer function between systolic arterial pressure and R-to-R interval, indicating that integrated baroreflex sensitivity was similar between the two conditions. These data show that breathing against inspiratory resistance increases tolerance to progressive central hypovolemia by better maintaining SV, cardiac output, and arterial blood pressures via primarily mechanical rather than neural mechanisms.

Lactate, pyruvate, glucose, and free fatty acid in mixed venous and arterial blood

1963 ◽  
Vol 18 (5) ◽  
pp. 933-936 ◽  
Author(s):  
P. Harris ◽  
T. Bailey ◽  
M. Bateman ◽  
M. G. Fitzgerald ◽  
J. Gloster ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Cardiac Output ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Venous Blood ◽  
Average Concentration ◽  
Mixed Venous Blood ◽  
Arterial Blood ◽  
Acquired Heart Disease ◽  
Mixed Venous

The concentrations of lactic acid, pyruvic acid, glucose, and free fatty acids have been measured simultaneously in the blood from the pulmonary and brachial arteries at rest and during exercise in a group of patients with acquired heart disease. The arteriovenous differences in the concentration of lactate, pyruvate, and free fatty acid were such as could be attributed to chance. The average concentration of glucose was slightly but significantly higher in the brachial arterial blood than in the mixed venous blood. cardiac output; lung metabolism; exercise Submitted on January 15, 1963

In Vivo Analysis of Gas Transport in Arterial and Venous Blood of the Sea Lamprey Petromyzon Marinus

1992 ◽  
Vol 169 (1) ◽  
pp. 105-119
Author(s):  
B. L. TUFTS ◽  
B. BAGATTO ◽  
B. CAMERON
Keyword(s):  
Partial Pressure ◽  
Whole Blood ◽  
Venous Blood ◽  
Recovery Period ◽  
Co2 Concentration ◽  
Extracellular Acidosis ◽  
Arterial Blood ◽  
Sea Lampreys ◽  
In Vivo Analysis

Exercise in sea lampreys resulted in a significant decrease in the extracellular pH (pHe) in both arterial and venous blood. At rest, the erythrocyte pH (pHi) of venous blood was significantly greater than the pHi of arterial blood. Despite the considerable extracellular acidosis after exercise, both arterial and venous pHi were maintained throughout the recovery period. In the venous blood, there was a reversal of the pH gradient (ΔpH) across the erythrocyte membrane immediately after exercise. Exercise also resulted in significant reductions in the partial pressure of oxygen and hemoglobin oxygen-carriage and a significant increase in the partial pressure of CO2 in arterial and venous blood. Although the total CO2 concentration of the plasma decreased after exercise, erythrocyte total CO2 concentrations (CCOCO2,i) increased. In venous blood, the CCOCO2,i immediately after exercise was double the resting value. At rest, partitioning of the total CO2 content between plasma and erythrocytes indicated that 16 % and 22 % of the total CO2 could be attributed to the erythrocytes in arterial and venous whole blood, respectively. After exercise, these percentages increased to 25% (arterial) and 38% (venous). Changes in CCOCO2,i accounted for 62% of the arteriovenous difference in whole-blood total CO2 at rest. This increased to 78% immediately after exercise. Thus, unlike other vertebrates, CO2 transport in the lamprey in vivo is largely dependent on erythrocyte CO2-carriage.

Cardiovascular and Respiratory Responses of Ducks to Progressive Hypocapnic Hypoxia

1972 ◽  
Vol 56 (3) ◽  
pp. 657-666
Author(s):  
DAVID R. JONES ◽  
GEORGE F. HOLETON
Keyword(s):  
Cardiac Output ◽  
Venous Blood ◽  
Minute Volume ◽  
Weight Basis ◽  
Lower Heart Rate ◽  
Pekin Ducks ◽  
Arterial Blood ◽  
Simulated High Altitude ◽  
Muscovy Ducks ◽  
Respiratory Responses

1. Cardiac ouput, ventilatory minute volume and gaseous exchange at both tissues and lungs have been recorded in restrained unanaesthetized ducks exposed to simulated high altitudes. 2. A comparison between two species of duck showed that despite a significantly lower heart rate in resting Muscovy ducks, cardiac output, on a weight basis, was the same as in White Pekin ducks. Respiratory frequency and tidal volumes differed in the two species although their minute volumes were in the same range. 3. Ducks responded to reduction in oxygen tension of arterial blood (Pa, o2) by increases in cardiac output and ventilatory minute volume, both being significantly above control (normal Pa, o2 at rest) when Pa, o2 was in the range 54.5-63 mmHg. At all levels of hypoxia ducks were able to remove about 30% of the oxygen from the ventilated air. 4. When Pa, o2 was 38 mmHg the Po2, difference between arterial and venous blood had decreased by 20.5 mmHg from control. Pa,co2, and Pvco2 fell during hypoxia and arterial and venous pH rose. 5. The rate of oxygen uptake (V· o2) fell markedly at the lowest level of hypoxia but V· co2, remained constant so that R.Q. rose from 0.76 at control at 1.12 at Pa, o2 of 38 mmHg. 6. It is concluded that there are many basic similarities between the cardiovascular and respiratory responses of ducks and mammals when exposed to simulated high altitude.

Effect of sympathetic blockade on diurnal variation of hemodynamic patterns

1989 ◽  
Vol 256 (3) ◽  
pp. R778-R785 ◽  
Author(s):  
M. I. Talan ◽  
B. T. Engel
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiac Output ◽  
Stroke Volume ◽  
Total Peripheral Resistance ◽  
Peripheral Resistance ◽  
Base Line ◽  
Sympathetic Blockade ◽  
Selective Blockade ◽  
Arterial Blood

Heart rate, stroke volume, and intra-arterial blood pressure were monitored continuously in each of four monkeys, 18 consecutive h/day for several weeks. The mean heart rate, stroke volume, cardiac output, systolic and diastolic blood pressure, and total peripheral resistance were calculated for each minute and reduced to hourly means. After base-line data were collected for approximately 20 days, observation was continued for equal periods of time under conditions of alpha-sympathetic blockade, beta-sympathetic blockade, and double sympathetic blockade. This was achieved by intra-arterial infusion of prazosin, atenolol, or a combination of both in concentration sufficient for at least 75% reduction of response to injection of agonists. The results confirmed previous findings of a diurnal pattern characterized by a fall in cardiac output and a rise in total peripheral resistance throughout the night. This pattern was not eliminated by selective blockade, of alpha- or beta-sympathetic receptors or by double sympathetic blockade; in fact, it was exacerbated by sympathetic blockade, indicating that the sympathetic nervous system attenuates these events. Because these findings indicate that blood volume redistribution is probably not the mechanism mediating the observed effects, we have hypothesized that a diurnal loss in plasma volume may mediate the fall in cardiac output and that the rise in total peripheral resistance reflects a homeostatic regulation of arterial pressure.

A field versus laboratory study of blood oxygen status in normoxic crabs at different temperatures

1996 ◽  
Vol 74 (3) ◽  
pp. 423-430 ◽  
Author(s):  
J.-C. Massabuau ◽  
J. Forgue
Keyword(s):  
Wide Spectrum ◽  
Venous Blood ◽  
Carcinus Maenas ◽  
Blood Oxygen ◽  
Arterial Blood ◽  
Field Versus ◽  
Partial Pressures ◽  
Different Temperatures ◽  
Head Pressure ◽  
Oxygen Status

The blood oxygen status of two species of active crabs (Carcinus maenas and Necora puber) was studied in the field and compared with the results of previous laboratory experiments performed on a wide spectrum of physiologically different water-breathers. The aim was to determine whether, as in the laboratory, the functioning of the O2 supply system in the field could be based on maintaining the arterial [Formula: see text] in the low range, 1–3 kPa. The O2 partial pressures and concentrations in the arterial and venous blood, arterial blood pH, and blood respiratory pigment concentration were measured in normoxic water at various temperatures ranging from 10 to 20 °C and in various seasons. In the field, [Formula: see text] values in normoxic C. maenas and N. puber were in the low range, 1–3 kPa, independently of temperature, season, and blood haemocyanin concentration. It is concluded that in the field as in the laboratory, [Formula: see text] values mainly in the low range provide a head pressure sufficient to meet O2 needs. The changes that appear to occur in other respiratory variables are discussed in relation to field versus laboratory conditions and temperature differences. The consequences for analysing problems of hypoxaemia in hypoxic waters or situations are discussed.

Effect of Bilateral Occlusion of Common Carotid Arteries on Cardiac Output and Oxygen Content of Arterial and Venous Blood in the Anesthetized Dog

1956 ◽  
Vol 185 (3) ◽  
pp. 483-486 ◽  
Author(s):  
Shirley H. Brind ◽  
Joseph R. Bianchine ◽  
Matthew N. Levy
Keyword(s):  
Cardiac Output ◽  
Oxygen Content ◽  
Venous Blood ◽  
Carotid Occlusion ◽  
Systemic Hypertension ◽  
Arterial Blood ◽  
Venous Oxygen Content ◽  
Bilateral Carotid Occlusion ◽  
Bilateral Carotid ◽  
Common Carotid Arteries

Changes in cardiac output, mean arterial blood pressure, hematocrit ratio, and arterial and venous oxygen content resulting from bilateral carotid occlusion were investigated. Cardiac output exhibited no significant alteration during endosinusal hypotension, and the systemic hypertension engendered was attributed to an increase in vasomotor tone. Arterial and venous oxygen content, as well as hematocrit ratio, increased significantly during the period of carotid occlusion. This increase was ascribed to splenic contraction evoked by carotid occlusion, since no comparable augmentation was observed when the splenic circulation was temporarily interrupted.

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