Oxygen delivery in lambs: cardiovascular and hematologic development

1979 ◽  
Vol 237 (6) ◽  
pp. H668-H675 ◽  
Author(s):  
G. Lister ◽  
T. K. Walter ◽  
H. T. Versmold ◽  
P. R. Dallman ◽  
A. M. Rudolph
Keyword(s):  
Cardiac Output ◽  
Oxygen Consumption ◽  
Oxygen Delivery ◽  
Venous Blood ◽  
Oxygen Affinity ◽  
Fetal Hemoglobin ◽  
Hemoglobin Concentration ◽  
Mixed Venous Blood ◽  
Hemoglobin Oxygen Affinity ◽  
Very High

After birth a decrease in hemoglobin concentration occurs while high metabolic demands are imposed on the infant by the extrauterine environment. Using the resting lamb as a model, we studied the mechanisms that are called into play during this period to maintain oxygen delivery. Measurements were made of oxygen consumption, arterial and mixed venous blood oxygen contents, cardiac output, hemoglobin concentration, percent fetal hemoglobin, 2,3-diphosphoglycerate, and hemoglobin oxygen affinity during the first two postnatal months. There was a rapid decrease in hemoglobin concentration after birth and concomitant decrease in hemoglobin oxygen affinity, changes similar to those described in humans. Cardiac output and oxygen consumption were both very high immediately after birth and declined in parallel, so that arteriovenous oxygen content difference was constant. Thus at rest cardiac output varies as a result of the changing need for oxygen. This relationship is independent of hemoglobin concentration or oxygen affinity within the normal range. If, however, oxygen demands were increased, oxygen delivery might be compromised by a limited ability to increase oxygen extraction during the immediate newborn period or when hemoglobin concentration is lowest.

Oxygen delivery, oxygen consumption and hemoglobin-oxygen affinity in acute myocardial infarction

1989 ◽  
Vol 64 (16) ◽  
pp. 975-979 ◽  
Author(s):  
Tsutomu Sumimoto ◽  
Yasuo Takayama ◽  
Toshiji Iwasaka ◽  
Tetsuro Sugiura ◽  
Masaharu Takeuchi ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Acute Myocardial Infarction ◽  
Oxygen Consumption ◽  
Oxygen Delivery ◽  
Oxygen Affinity ◽  
Hemoglobin Oxygen Affinity

Tolerance to Acute Isovolemic Hemodilution

2003 ◽  
Vol 99 (1) ◽  
pp. 97-104 ◽  
Author(s):  
Philippe Van der Linden ◽  
Stefan De Hert ◽  
Nathalie Mathieu ◽  
Françoise Degroote ◽  
Denis Schmartz ◽  
...  
Keyword(s):  
Cardiac Output ◽  
Oxygen Consumption ◽  
Oxygen Delivery ◽  
Oxygen Demand ◽  
Hemoglobin Concentration ◽  
Perioperative Period ◽  
Isovolemic Hemodilution ◽  
Anesthetic Depth ◽  
Output Response ◽  
Critical Oxygen

Background Acceptance of a lower transfusion trigger in the perioperative period requires study of the effects of anesthetic depth on the tolerance to acute isovolemic anemia. Anesthetic agents with negative effects on the cardiovascular system may exert proportionately greater depressant effects on cardiac output response than on tissue oxygen demand, reducing tolerance to acute isovolemic anemia. Methods In the first study, animals were anesthetized with halothane (n = 14; 23.8 +/- 4.8 kg, mean +/- SD). In a second study, animals were anesthetized with ketamine (n = 14; 24.3 +/- 4.7 kg). In each study, dogs were randomly allocated to receive either low or high concentrations of anesthetic. Oxygen delivery and oxygen consumption were determined from independent measurements during a stepwise isovolemic hemodilution protocol. In each dog, critical oxygen delivery was determined from a plot of oxygen consumption versus oxygen delivery using a least-sum-of-squares technique. Critical hemoglobin (hemoglobin) was determined from a plot of hemoglobin versus oxygen consumption using the same method. Results With both agents, the higher anesthetic concentration was associated with decreased oxygen consumption, resulting in a lower critical oxygen delivery. However, critical hemoglobin was significantly higher in the animals receiving the higher anesthetic dosage (1.5 vs. 1.0 minimum alveolar concentration of halothane: 4.1 +/- 1.3 vs. 2.3 +/- 0.5 g/dl, P < 0.05; high- vs. low-dose ketamine: 3.7 +/- 1.4 vs. 2.5 +/- 0.6 g/dl, P < 0.05). This was related to a marked blunting of the cardiac output response to hemodilution in the animals receiving the higher anesthetic dosage. Conclusions Increased anesthetic depth with halothane or ketamine resulted in a decreased tolerance to acute anemia, as reflected by a significant increase in critical hemoglobin concentration.

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.

Influence of changes in cardiac output on the acid-base status of arterial and mixed venous blood

1987 ◽  
Vol 410 (3) ◽  
pp. 257-262 ◽  
Author(s):  
Y. L. Hoogeveen ◽  
J. P. Zock ◽  
P. Rispens ◽  
W. G. Zijlstra
Keyword(s):  
Cardiac Output ◽  
Venous Blood ◽  
Mixed Venous Blood ◽  
Acid Base ◽  
Acid Base Status ◽  
Mixed Venous

scholarly journals Maximal Fat Oxidation: Comparison between Treadmill, Elliptical and Rowing Exercises

2021 ◽  
pp. 170-178
Author(s):  
Michelle Filipovic ◽  
Stephanie Munten ◽  
Karl-Heinz Herzig ◽  
Dominique D. Gagnon
Keyword(s):  
Oxygen Consumption ◽  
Venous Blood ◽  
Maximal Oxygen Consumption ◽  
Blood Gases ◽  
Fat Oxidation ◽  
Peak Oxygen Consumption ◽  
Whole Body ◽  
Mixed Venous Blood ◽  
Exercise Modality ◽  
Maximal Fat Oxidation

Fat oxidation during exercise is associated with cardio-metabolic benefits, but the extent of which whole-body exercise modality elicits the greatest fat oxidation remains unclear. We investigated the effects of treadmill, elliptical and rowing exercise on fat oxidation in healthy individuals. Nine healthy males participated in three, peak oxygen consumption tests, on a treadmill, elliptical and rowing ergometer. Indirect calorimetry was used to assess maximal oxygen consumption (V̇O2peak), maximal fat oxidation (MFO) rates, and the exercise intensity MFO occurred (Fatmax). Mixed venous blood was collected to assess lactate and blood gases concentrations. While V̇O2peak was similar between exercise modalities, MFO rates were higher on the treadmill (mean ± SD; 0.61 ± 0.06 g·min-1) compared to both the elliptical (0.41 ± 0.08 g·min-1, p = 0.022) and the rower (0.40 ± 0.08 g·min-1, p = 0.017). Fatmax values were also significantly higher on the treadmill (56.0 ± 6.2 %V̇O2peak) compared to both the elliptical (36.8 ± 5.4 %V̇O2peak, p = 0.049) and rower (31.6 ± 5.0 %V̇O2peak, p = 0.021). Post-exercise blood lactate concentrations were also significantly lower following treadmill exercise (p = 0.021). Exercising on a treadmill maximizes fat oxidation to a greater extent than elliptical and rowing exercises, and remains an important exercise modality to improve fat oxidation, and consequently, cardio-metabolic health.

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

Measurement of inotropy and systemic oxygen delivery in term, low- and very-low-birth-weight neonates using the Ultrasonic Cardiac Output Monitor (USCOM)

2020 ◽  
Vol 48 (3) ◽  
pp. 289-295
Author(s):  
Man-Li Zheng ◽  
Shao-Ru He ◽  
Yu-Mei Liu ◽  
Lin Chen
Keyword(s):  
Cardiac Output ◽  
Birth Weight ◽  
Low Birth Weight ◽  
Pulse Oximetry ◽  
Oxygen Delivery ◽  
Very Low Birth Weight ◽  
Hemoglobin Concentration ◽  
Systemic Oxygen Delivery ◽  
Systemic Oxygen ◽  
Cardiac Output Monitor

AbstractBackgroundThe aim of this study was to assess the normal values of the Smith-Madigan inotropy index (SMII) and oxygen delivery index (DO2I) in low-birth-weight (LBW) and very-low-birth-weight (VLBW) newborns on the first 3 days of life, and to identify how different degrees of maturity influence cardiovascular alterations during the transitional period compared with term neonates.MethodsTwenty-eight VLBW newborns, 46 LBW newborns and 50 normal full-term newborns admitted to our department were studied. Hemodynamics of the left heart were measured in all neonates over the first 3 days using the Ultrasonic Cardiac Output Monitor (USCOM). This was combined with hemoglobin concentration and pulse oximetry to calculate DO2I. Blood pressure was combined with the hemodynamic measures and hemoglobin concentration to calculate SMII.ResultsSMII showed statistically significant differences among the three groups (VLBW 0.48 ± 0.11; LBW 0.54 ± 0.13; term 0.69 ± 0.17 W/m2 P < 0.001), which was in line with the following myocardial parameters: stroke volume index (SVI) and cardiac index (CI) (P < 0.001 and <0.001). For systemic oxygen delivery (DO2) parameters, significant differences were found for DO2I (P < 0.001) while hemoglobin concentration and pulse oximetry demonstrated no significant differences. In the VLBW group, SMII and DO2I showed no significant change over the 3 days.ConclusionNormal inotropy and systemic DO2I values in VLBW neonates over the first 3 days of life were assessed. SMII and DO2I were significantly lower in VLBW neonates during the first 72 h of life. With increasing birth weight, higher myocardial inotropy and DO2 were found. The addition of USCOM examination to standard neonatal echocardiography may provide further important information regarding cardiac function.

scholarly journals Postpneumonectomy alveolar growth does not normalize hemodynamic and mechanical function

1999 ◽  
Vol 87 (2) ◽  
pp. 491-497 ◽  
Author(s):  
Shin-Ichi Takeda ◽  
Murugappan Ramanathan ◽  
Aaron S. Estrera ◽  
Connie C. W. Hsia
Keyword(s):  
Cardiac Output ◽  
Minute Ventilation ◽  
Lung Resection ◽  
Venous Blood ◽  
Structural Response ◽  
Respiratory Muscles ◽  
Blood Gases ◽  
Mixed Venous Blood ◽  
Power Requirement ◽  
Normal Mean

Immature foxhounds underwent 55% lung resection by right pneumonectomy ( n = 5) or thoracotomy without pneumonectomy (Sham, n = 6) at 2 mo of age. Cardiopulmonary function was measured during treadmill exercise on reaching maturity 1 yr later. In pneumonectomized animals compared with Sham animals, maximal oxygen uptake, ventilatory response, and cardiac output during exercise were normal. Arterial and mixed venous blood gases and arteriovenous oxygen extraction during exercise were also normal. Mean pulmonary arterial pressure and resistance were elevated at a given cardiac output. Dynamic ventilatory power requirement was also significantly elevated at a given minute ventilation. These long-term hemodynamic and mechanical abnormalities are in direct contrast to the normal pulmonary gas exchange during exercise in these same pneumonectomized animals reported elsewhere (S. Takeda, C. C. W. Hsia, E. Wagner, M. Ramanathan, A. S. Estrera, and E. R. Weibel. J. Appl. Physiol. 86: 1301–1310, 1999). Functional compensation was superior in animals pneumonectomized as puppies than as adults. These data indicate a limited structural response of conducting airways and extra-alveolar pulmonary blood vessels to pneumonectomy and suggest the development of other sources of adaptation such as those involving the heart and respiratory muscles.

scholarly journals OXYGEN TRANSPORT IN MARINE GREEN TURTLE (CHELONIA MYDAS) HATCHLINGS: BLOOD VISCOSITY AND CONTROL OF HEMOGLOBIN OXYGEN-AFFINITY

1994 ◽  
Vol 188 (1) ◽  
pp. 103-114 ◽  
Author(s):  
R Wells ◽  
J Baldwin
Keyword(s):  
Blood Viscosity ◽  
Green Turtle ◽  
Oxygen Affinity ◽  
Hemoglobin Concentration ◽  
Chelonia Mydas ◽  
Oxygen Binding ◽  
Mean Cell Volume ◽  
Hemoglobin Oxygen Affinity ◽  
Oxygen Carrying Capacity ◽  
And Control

Erythrocytes from green turtle hatchlings contain a single embryonic component, unlike those from other cleidoic eggs, in which adult hemoglobin (Hb) constitutes a significant fraction of total Hb at hatching. The functional properties of the isolated and purified green turtle hatchling Hb that distinguish it from adult Hb are a high affinity for oxygen and marked sensitivity to organic phosphate modulators. Hatchling erythrocytes also contain higher concentrations of ATP and 2,3-diphosphoglyceric acid, but their oxygen affinity is indistinguishable from that of adult erythrocytes. Hatchling erythrocyte mean cell volume is approximately half of the adult value, but hematocrit, blood hemoglobin concentration and blood viscosity of hatchlings and adults are similar. Oxygen-carrying capacity in green turtles, unlike that of other diving vertebrates, corresponds with a theoretically derived optimum. The possibility of allosteric control of Hb oxygen-binding in hatchlings may relate not to the challenge of exercise during the dispersal phase but to conditions in the late embryo in the nest.

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