scholarly journals Effect of Exercise-Induced Reductions in Blood Volume on Cardiac Output and Oxygen Transport Capacity

2021 ◽  
Vol 12 ◽  
Author(s):  
Janis Schierbauer ◽  
Torben Hoffmeister ◽  
Gunnar Treff ◽  
Nadine B. Wachsmuth ◽  
Walter F. J. Schmidt
Keyword(s):  
Cardiac Output ◽  
Stroke Volume ◽  
Oxygen Saturation ◽  
Blood Volume ◽  
Oxygen Transport ◽  
Arterial Oxygen ◽  
Peripheral Oxygen Saturation ◽  
Heart Volume ◽  
Arterial Oxygen Content ◽  
Oxygen Transport Capacity

We wanted to demonstrate the relationship between blood volume, cardiac size, cardiac output and maximum oxygen uptake (V.O2max) and to quantify blood volume shifts during exercise and their impact on oxygen transport. Twenty-four healthy, non-smoking, heterogeneously trained male participants (27 ± 4.6 years) performed incremental cycle ergometer tests to determine V.O2max and changes in blood volume and cardiac output. Cardiac output was determined by an inert gas rebreathing procedure. Heart dimensions were determined by 3D echocardiography. Blood volume and hemoglobin mass were determined by using the optimized CO-rebreathing method. The V.O2max ranged between 47.5 and 74.1 mL⋅kg–1⋅min–1. Heart volume ranged between 7.7 and 17.9 mL⋅kg–1 and maximum cardiac output ranged between 252 and 434 mL⋅kg–1⋅min–1. The mean blood volume decreased by 8% (567 ± 187 mL, p = 0.001) until maximum exercise, leading to an increase in [Hb] by 1.3 ± 0.4 g⋅dL–1 while peripheral oxygen saturation decreased by 6.1 ± 2.4%. There were close correlations between resting blood volume and heart volume (r = 0.73, p = 0.002), maximum blood volume and maximum cardiac output (r = 0.68, p = 0.001), and maximum cardiac output and V.O2max (r = 0.76, p < 0.001). An increase in maximum blood volume by 1,000 mL was associated with an increase in maximum stroke volume by 25 mL and in maximum cardiac output by 3.5 L⋅min–1. In conclusion, blood volume markedly decreased until maximal exhaustion, potentially affecting the stroke volume response during exercise. Simultaneously, hemoconcentrations maintained the arterial oxygen content and compensated for the potential loss in maximum cardiac output. Therefore, a large blood volume at rest is an important factor for achieving a high cardiac output during exercise and blood volume shifts compensate for the decrease in peripheral oxygen saturation, thereby maintaining a high arteriovenous oxygen difference.

Systemic oxygen transport in induced normovolemic anemia and polycythemia

1962 ◽  
Vol 203 (4) ◽  
pp. 720-724 ◽  
Author(s):  
John F. Murray ◽  
Philip Gold ◽  
B. Lamar Johnson
Keyword(s):  
Cardiac Output ◽  
Oxygen Transport ◽  
Arterial Oxygen Saturation ◽  
Peripheral Resistance ◽  
Arterial Oxygen ◽  
Peripheral Vascular ◽  
Arterial Oxygen Content ◽  
Normovolemic Anemia ◽  
Systemic Oxygen ◽  
Negative Linear Relationship

The hemodynamic effects of normovolemic anemia and polycythemia were studied in 14 dogs. Anemia (5 dogs) and polycythemia (5 dogs) were induced by bleeding and simultaneously infusing dextran or packed erythrocytes. Measurements included cardiac output, arterial oxygen saturation, peripheral vascular resistance, and systemic oxygen transport (cardiac output X arterial oxygen content). Cardiac output had a significant negative linear relationship to hematocrit ( r = –0.74, P < 0.01) over the range studied (13–74%). Peripheral resistance fell 46% in anemic animals and increased 152% in four of five polycythemic animals. Arterial saturation was significantly correlated to changes in hematocrit ( r = 0.62, P < 0.01) and cardiac output ( r = –0.55, P < 0.01); these values were due primarily to the linearity encountered in the anemia experiments and a reversal in these relationships tended to occur at high hematocrits. Systemic oxygen transport was maximum at normal hematocrits and decreased in anemia and polycythemia. The data indicate that hemodynamic adjustments in normovolemic anemia and polycythemia are insufficient to maintain normal oxygen delivery.

Cardiac limitation to maximal oxygen transport and changes in components after jogging across the US

1975 ◽  
Vol 39 (6) ◽  
pp. 958-964 ◽  
Author(s):  
R. A. Bruce ◽  
F. Kusumi ◽  
B. H. Culver ◽  
J. Butler
Keyword(s):  
Stroke Volume ◽  
Oxygen Transport ◽  
Cell Mass ◽  
Young Male ◽  
The United States ◽  
Systemic Arterial Pressure ◽  
Arterial Oxygen ◽  
Total Blood ◽  
Male Adult ◽  
Arterial Oxygen Content

Observations were made before and 3–5 days after prolonged endurance jogging an average of 42 miles/day, 6 days/wk for 2.5 mo by a young male adult who voluntarily initiated a run across the United States. Both arterial PO2 and lactic acid increased. In each instance, the first limitation in circulatory delivery of oxygen was a plateau in stroke volume and cardiac output. Afterward, pulse deficit and systemic arterial pressure fell with exercise and heart rate accelerated. Although there was no change in oxygen transport (Q X CAO2), a reduction in stroke volume was exactly balanced by a rise in arterial oxygen content. Vital capacity, residual volume, and total lung capacity and diffusion capacity for carbon monoxide, hematocrit, and red cell mass increased, while plasma volume diminished and heart size and total blood volume were unchanged.

Cardio-respiratory and metabolic responses to different levels of compression during submaximal exercise

2011 ◽  
Vol 26 (3) ◽  
pp. 102-106 ◽  
Author(s):  
B Sperlich ◽  
M Haegele ◽  
M Krüger ◽  
T Schiffer ◽  
H-C Holmberg ◽  
...  
Keyword(s):  
Heart Rate ◽  
Cardiac Output ◽  
Oxygen Uptake ◽  
Stroke Volume ◽  
Oxygen Saturation ◽  
Arterial Oxygen Saturation ◽  
Peak Oxygen Uptake ◽  
Submaximal Exercise ◽  
Arterial Oxygen ◽  
Different Levels

Objective The effects of knee-high socks that applied different levels of compression (0, 10, 20, 30 and 40 mmHg) on various cardio-respiratory and metabolic parameters during submaximal running were analysed. Methods Fifteen well-trained, male endurance athletes (age: 22.2 ± 1.3 years; peak oxygen uptake: 57.2 ± 4.0 mL/minute/kg) performed a ramp test to determine peak oxygen uptake. Thereafter, all athletes carried out five periods of submaximal running (at approximately 70% of peak oxygen uptake) with and without compression socks that applied the different levels of pressure. Cardiac output and index, stroke volume, arterio-venous difference in oxygen saturation, oxygen uptake, arterial oxygen saturation, heart rate and blood lactate were monitored before and during all of these tests. Results Cardiac output ( P = 0.29) and index ( P = 0.27), stroke volume ( P = 0.50), arterio-venous difference in oxygen saturation ( P = 0.11), oxygen uptake ( P = 1.00), arterial oxygen saturation ( P = 1.00), heart rate ( P = 1.00) and arterial lactate concentration ( P = 1.00) were unaffected by compression (effect sizes = 0.00–0.65). Conclusion This first evaluation of the potential effects of increasing levels of compression on cardio-respiratory and metabolic parameters during submaximal exercise revealed no effects whatsoever.

Level of ventilation influences the cardiovascular response to hypoxemia in lambs

2004 ◽  
Vol 82 (12) ◽  
pp. 1113-1117 ◽  
Author(s):  
James E Fewell ◽  
Bonnie J Taylor
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiac Output ◽  
Oxygen Transport ◽  
Cardiovascular Response ◽  
Recovery Period ◽  
Arterial Oxygen ◽  
Arterial Oxygen Content ◽  
Systemic Oxygen ◽  
Cardiovascular Variables

Newborn animals of a number of species display a brisk increase in ventilation followed by a gradual drop toward or below baseline within minutes of exposure to acute hypoxemia. Heart rate and cardiac output (a determinant of systemic oxygen transport along with the arterial oxygen content) appear to follow a similar pattern, but whether or not the cardiovascular response is influenced by the respiratory response is unknown. We therefore carried out experiments in which the level of ventilation was controlled during normoxemia and hypoxemia to test the hypothesis that the level of ventilation influences the cardiovascular response to acute hypoxemia. Six lambs ranging in age from 17 to 22 days were anesthetized, tracheostomized, and instrumented for measurement of cardiovascular variables. A recovery period of at least 3 days was allowed before the study when each lamb was artificially ventilated with a mixture of 70% nitrous oxide and 30% oxygen in nitrogen. A control respiratory frequency (f) of 30 breaths per min was set and a control tidal volume (VT) was chosen to achieve normocapnia. Cardiovascular measurements were made during normoxemia and hypoxemia (FIO2 0.10) 5 min after f or VT was changed to simulate a decrease, no change, or an increase in ventilation. During normoxemia, the level of ventilation had little effect on the measured cardiovascular variables. At control levels of ventilation, hypoxemia caused an increase in cardiac output that was due solely to an increase in stroke volume as heart rate decreased; blood pressure was unchanged. Increasing ventilation during hypo xemia did not augment cardiac output or alter blood pressure as compared with that observed at control levels of ventilation. Decreasing ventilation during hypoxemia, however, decreased cardiac output due to a profound bradycardia; blood pressure increased significantly. Our data provide evidence that the level of ventilation significantly influences the cardiovascular response to hypoxemia in young lambs.Key words: newborn, hypoxemia, cardiovascular, respiration, systemic oxygen transport.

Long-term hemodynamic actions of atrial natriuretic factor (99-126) in conscious sheep

1988 ◽  
Vol 254 (4) ◽  
pp. H811-H815 ◽  
Author(s):  
D. G. Parkes ◽  
J. P. Coghlan ◽  
J. G. McDougall ◽  
B. A. Scoggins
Keyword(s):  
Blood Pressure ◽  
Cardiac Output ◽  
Stroke Volume ◽  
Blood Volume ◽  
Total Peripheral Resistance ◽  
Atrial Natriuretic Factor ◽  
Peripheral Resistance ◽  
Natriuretic Factor ◽  
Atrial Natriuretic

The hemodynamic and metabolic effects of long-term (5 day) infusion of human atrial natriuretic factor (ANF) were examined in conscious chronically instrumented sheep. Infusion of ANF at 20 micrograms/h, a rate below the threshold for an acute natriuretic effect, decreased blood pressure by 9 +/- 1 mmHg on day 5, associated with a fall in calculated total peripheral resistance. On day 1, ANF reduced cardiac output, stroke volume, and blood volume, effects that were associated with an increase in heart rate and calculated total peripheral resistance and a small decrease in blood pressure. On days 4 and 5 there was a small increase in urine volume and sodium excretion. On day 5 an increase in water intake and body weight was observed. No change was seen in plasma concentrations of renin, arginine vasopressin, glucose, adrenocorticotropic hormone, or protein. This study suggests that the short-term hypotensive effect of ANF results from a reduction in cardiac output associated with a fall in both stroke volume and effective blood volume. However, after 5 days of infusion, ANF lowers blood pressure via a reduction in total peripheral resistance.

Saturation of arterial blood with oxygen during maximal exercise

1964 ◽  
Vol 19 (2) ◽  
pp. 284-286 ◽  
Author(s):  
Loring B. Rowell ◽  
Henry L. Taylor ◽  
Yang Wang ◽  
Walter S. Carlson
Keyword(s):  
Oxygen Saturation ◽  
Arterial Oxygen Saturation ◽  
Arterial Oxygen ◽  
Oxygen Intake ◽  
Arterial Oxygen Content ◽  
Good Physical Condition ◽  
Arterial Blood ◽  
Sedentary Group ◽  
Arterial Desaturation ◽  
Sufficient Intensity

The per cent saturation of the arterial blood with oxygen was examined in four men before and during the last 15 sec of a 3-min run of sufficient intensity to elicit a maximal oxygen intake. The measurements were repeated after a 3-month period of intensive conditioning for middle distance running and in a group of four athletes in good physical condition. The per cent saturation in the sedentary group was 95.8 at rest and 93.4 during exhausting exercise; after conditioning the similar figures were 95.4 and 91.4 and, finally, the athletes showed a per cent saturation of 85.2 during the heavy work. The arterial oxygen content during exhausting work was found to be 20.12 ml/100 ml blood in the sedentary group before training, 19.02 after conditioning, and 18.18 in the group of athletes. It is concluded that, in athletes who are well conditioned and pushing themselves close to the limit of their capacity, arterial desaturation can take place. athletic conditioning and arterial oxygen saturation; arterial desaturation in athletes; ventilation and arterial desaturation; oxygen intake and arterial oxygen saturation Submitted on August 5, 1963

scholarly journals Effects of Hematocrit Variations on Cerebral Blood Flow and Oxygen Transport in Ischemic Cerebrovascular Disease

1981 ◽  
Vol 1 (4) ◽  
pp. 413-417 ◽  
Author(s):  
Masahito Kusunoki ◽  
Kazufumi Kimura ◽  
Masaichi Nakamura ◽  
Yoshinari Isaka ◽  
Shotaro Yoneda ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Cerebrovascular Disease ◽  
Oxygen Transport ◽  
Oxygen Delivery ◽  
Inverse Correlation ◽  
Arterial Oxygen ◽  
Brain Oxygenation ◽  
Arterial Oxygen Content ◽  
Ischemic Cerebrovascular Disease

The contribution of hematocrit (Ht) changes on cerebral blood flow (CBF) and brain oxygenation in ischemic cerebrovascular disease is still controversial. In the present study, effects of Ht variations on CBF and oxygen delivery were investigated in patients with ischemic cerebrovascular disease. CBF was measured by the Xe-133 intracarotid injection method in 27 patients, whose diagnoses included completed stroke, reversible ischemic neurological deficit, and transient ischemic attack. Ht values in the patients ranged from 31 to 53%. There was a significant inverse correlation between CBF and Ht in these Ht ranges. Oxygen delivery, i.e., the product of arterial oxygen content and CBF, increased with Ht elevation and reached the maximum level in the Ht range of 40–45% and then declined. The CBF-Ht and oxygen transport-Ht relations observed in our study were similar to those in the glass-tube model studies by other workers rather than to those in intact animal experiments. From these results, it is conceivable that in ischemic cerebrovascular disease, the vasomotor adjustment was impaired in such a manner that the relations among Ht, CBF, and oxygen delivery were different from those in healthy subjects. Further, an “optimal hematocrit” for brain oxygenation was also discussed.

scholarly journals Polycythemia Associated with Disturbed Function of the Respiratory Center

Blood ◽  
1956 ◽  
Vol 11 (12) ◽  
pp. 1077-1084 ◽  
Author(s):  
PETER PARE ◽  
LOUIS LOWENSTEIN
Keyword(s):  
Oxygen Saturation ◽  
Blood Volume ◽  
Unusual Case ◽  
Arterial Oxygen Saturation ◽  
Respiratory Center ◽  
Arterial Oxygen ◽  
Disturbed Function

Abstract 1. An unusual case of absolute polycythemia associated with hypoxemia, probably resulting from abnormal function of the respiratory center has been presented. 2. The mechanism of development of this type of polycythemia has been discussed. 3. A classification of polycythemia on the basis of blood volume and arterial oxygen saturation has been suggested.

Sign in / Sign up

Export Citation Format

Share Document