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.

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.

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.

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

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.

New implanted chronic catheter device for determining blood pressure and cardiac output in conscious dog

1985 ◽  
Vol 249 (3) ◽  
pp. H681-H684 ◽  
Author(s):  
D. Garner ◽  
M. M. Laks
Keyword(s):  
Blood Pressure ◽  
Cardiac Output ◽  
Arterial Blood Pressure ◽  
Blood Pressure Monitoring ◽  
Venous Blood ◽  
Blood Sampling ◽  
Pressure Monitoring ◽  
Access Port ◽  
Arterial Blood ◽  
Venous Blood Sampling

The Vascular-Access-Port (VAP) is a subcutaneous implantable device designed for repeated venous blood sampling in humans. With slight modifications the device has been used in the arterial and venous systems of dogs. This device allows for chronic repeated arterial blood pressure monitoring, monitoring of cardiac outputs, and blood sampling in conscious dogs. Infection, vascular thrombosis, and catheter extraction have not occurred. This modified VAP has been used for 6 mo and in 25 dogs to date without any failure to determine arterial blood pressure and cardiac output.

Regulation of Cardiac Output during 2,4-Dinitrophenol-Induced Tissue Hypermetabolism in the Dog

1977 ◽  
Vol 53 (1) ◽  
pp. 17-25
Author(s):  
C. Liang ◽  
W. B. Hood
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiac Output ◽  
Arterial Blood Pressure ◽  
Venous Blood ◽  
The Other ◽  
Pulmonary Artery Wedge Pressure ◽  
Systemic Arterial Blood Pressure ◽  
Arterial Blood ◽  
Wedge Pressure

1. Cardiac output increased in proportion to oxygen consumption in intact chloralose-anaesthetized dogs after four successive intravenous infusions of 2,4-dinitrophenol (11 μmol/kg; 2 mg/kg). 2. Splenectomy abolished the increase in cardiac output after the first three doses of 2,4-dinitrophenol. β-Adrenoreceptor blockade by practolol, on the other hand, did not prevent the cardiac output rise after the first 2,4-dinitrophenol infusion, but further increases by 2,4-dinitrophenol infusion were abolished. When splenectomy and β-adrenoreceptor blockade were combined, cardiac output did not increase significantly after all four doses of 2,4-dinitrophenol. 3. Cardiac output and mean systemic arterial blood pressure increased when the splenic venous blood collected after 2,4-dinitrophenol infusion was infused intraportally. 4. In a vascularly isolated, but normally innervated, lower half-body cross-perfusion preparation, cardiac output and mean systemic arterial blood pressure increased in the upper half-body when tissue hypermetabolism was produced in the cross-perfused area by 2,4-dinitrophenol. Neither pulmonary artery wedge pressure nor heart rate changed significantly. 5. This circulatory stimulation, after regional 2,4-dinitrophenol infusion, was abolished or was prevented from occurring by splenectomy. 6. It appears that the normal cardiac output response to tissue hypermetabolism requires both an intact spleen and normally functioning β-adrenoreceptors.

PHYSIOLOGIC AND CHEMICAL RESPONSE OF PREMATURE INFANTS TO OXYGEN-ENRICHED ATMOSPHERE

PEDIATRICS ◽  
1950 ◽  
Vol 6 (1) ◽  
pp. 55-71
Author(s):  
BRUCE D. GRAHAM ◽  
HELEN S. REARDON ◽  
JAMES L. WILSON ◽  
MAKEPEACE U. TSAO ◽  
MARY L. BAUMANN
Keyword(s):  
Body Weight ◽  
Oxygen Saturation ◽  
Premature Infants ◽  
Arterial Oxygen Saturation ◽  
Minute Volume ◽  
Significant Rise ◽  
Weight Basis ◽  
Arterial Oxygen ◽  
Regular Type ◽  
Arterial Blood

Arterial blood studies were performed on 44 premature infants while in atmosphere and greater concentrations of oxygen. Analyses were made for oxygen content, oxygen capacity and hematocrit. Concomitant plethysmographic studies were made on 29 occasions. Results were as follows: 1. Only 25% (7) of the premature infants studied breathed regularly in atmosphere; the remaining individuals breathed with some degree of periodicity (44%) or completely irregularly (30%). 2. As the concentration of oxygen being breathed was raised, then more of the group shifted to a regular type of respiration until when in 75-85% oxygen, 88% of the group then breathed with a regular type of respiration. 3. a. The percentage arterial oxygen saturation of the group averaged 93% in atmosphere, 96% in 30-55% oxygen, 100% saturation in 70-79% oxygen being breathed and 102% in 80-89% oxygen. b. In atmosphere, when compared on age basis, the younger group (1-14 days) had essentially the same arterial oxygen saturation as the older group (14-65 days). In an atmosphere of 70-90% oxygen, the saturation of the younger group increased to 102% while the older group rose to 100%. c. When compared on body weight basis, the 0.9-1.3 kg. group increased the arterial oxygen saturation of 85% in atmosphere to 102% when 70-85% oxygen was administered; the 1.3-1.8 kg. group, 93% to 101%; the 1.8-2.3 kg. group, 9% to 100%. (It is noted that either on age or body weight basis the group with higher hematocrit attained higher arterial oxygen saturation when 70-85% oxygen was administered than the group with lower hematocrit.) 4. a. A statistical analysis of the respiratory records revealed an average rise of 30% in minute volume when 30-40% oxygen was administered, this rise being significantly maintained as higher concentrations (to 90%) of oxygen were administered. b. An average significant rise in respiratory rate of 30% was noted when 30-40% oxygen was administered which slowly fell to the original rate level as oxygen administered was increased to 80-90% concentration. c. Consequently, the tidal volume (volume per respiration) gradually increased to 30% above the level in atmosphere as oxygen administered was increased to 80-90% concentration.

Effects of metabolic acidosis and alkalosis on coronary blood flow and myocardial metabolism in the intact dog

1961 ◽  
Vol 200 (3) ◽  
pp. 628-632 ◽  
Author(s):  
A. V. N. Goodyer ◽  
W. F. Eckhardt ◽  
R. H. Ostberg ◽  
M. J. Goodkind
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
Metabolic Acidosis ◽  
Coronary Blood Flow ◽  
Venous Blood ◽  
Left Ventricular ◽  
Myocardial Uptake ◽  
Severe Metabolic Acidosis ◽  
Glucose Levels ◽  
Arterial Blood

Severe metabolic acidosis and alkalosis were induced in anesthetized dogs by the infusion of solutions of hydrochloric acid and sodium bicarbonate. Infusions of sodium chloride were administered to other dogs under the same experimental circumstances. Measurements were made of arterial blood pressure, heart rate, cardiac output and coronary blood flow, arterial blood pH, and the content of oxygen, total CO2, lactate, pyruvate and glucose in both arterial and coronary venous blood. The cardiac output and coronary blood flow were decreased by acidosis and increased by alkalosis, the changes induced by alkalosis. There were no significant changes of left ventricular efficiency. Acidosis increased blood glucose concentrations and interfered with the increased myocardial uptake of glucose expected at higher arterial glucose levels. Alkalosis increased blood lactate and pyruvate levels and, correspondingly, the myocardial uptake of these carbohydrate substrates. It is concluded that cardiac dynamic function (as indicated by measurements of cardiac efficiency and output and arterial pressure) is much less affected by severe metabolic acidosis in the intact animal than in the isolated perfused organ.

Quantification of right-to-left shunt with 99mTc-labelled albumin macroaggregates and 100% oxygen in patients with hereditary haemorrhagic telangiectasia

2002 ◽  
Vol 102 (2) ◽  
pp. 127-134 ◽  
Author(s):  
Johannes J. MAGER ◽  
Pieter ZANEN ◽  
Fred VERZIJLBERGEN ◽  
Cornelius J.J. WESTERMANN ◽  
Tjeerd HAITJEMA ◽  
...  
Keyword(s):  
Cardiac Output ◽  
Oxygen Content ◽  
Venous Blood ◽  
Alternative Methods ◽  
Mixed Venous Blood ◽  
Hereditary Haemorrhagic Telangiectasia ◽  
Shunt Fraction ◽  
Limits Of Agreement ◽  
Arterial Blood ◽  
Pulmonary Capillaries

Pulmonary arteriovenous malformations (PAVMs) are often associated with hereditary haemorrhagic telangiectasia (HHT). The quantification of right-to-left shunts in patients with PAVMs is important in diagnosis and follow up. Traditionally, this shunt is measured by the 100% oxygen method, in which the value for the arteriovenous difference in oxygen content, Cao2-Co2 (where Cao2 is the oxygen content of arterial blood and Co2 is the oxygen content of mixed venous blood) is estimated. Alternative methods consist of measurement of the systemic or renal uptake of 99mTc-labelled macroaggregates of albumin (MAA), which are trapped in pulmonary capillaries, but pass through PAVMs. We first measured Cao2-Co2 in 12 HHT patients before and after embolization of PAVMs. We obtained a mean value of 4.4ml/100ml, instead of the usual 5ml/100ml. Subsequently, we measured right-to-left shunt in 21 HHT patients using the 100% oxygen method and with two different methods involving 99mTc. We used the kidney-lung method (K/L method), in which it is assumed that the right kidney receives 10% of the cardiac output, and we also used a method with two tracers (HSA/MAA method): (1) 99mTc-labelled human serum albumin (HSA) (which passes through pulmonary capillaries) to measure the fraction of the cardiac output perfusing the kidneys, and (2) MAA to measure the shunt fraction. In 35 shunt measurements we evaluated this new technique and the K/L method, by comparing the results with those from the 100% oxygen method. There was poor agreement between the 100% oxygen method and the K/L method, with 95% limits of agreement for the shunt fraction of -15.2% to +15.2%. There was moderate agreement between the 100% oxygen method and the HSA/MAA method, with limits of agreement of -8.3% to +7.7%. We conclude that the different methods cannot replace each other, because the limits of agreement are too wide for clinical use.

Comparison of CO2 rebreathing and acetylene methods for cardiac output

1965 ◽  
Vol 20 (4) ◽  
pp. 763-766 ◽  
Author(s):  
K. Klausen
Keyword(s):  
Cardiac Output ◽  
Partial Pressure ◽  
Venous Blood ◽  
Mixed Venous Blood ◽  
Co2 Rebreathing ◽  
Arterial Blood ◽  
Co2 Output ◽  
Partial Pressure Of Co2 ◽  
Douglas Bag ◽  
Rebreathing Method

The cardiac output during rest and work was determined by a CO2 rebreathing method as suggested by Defares. The partial pressure of CO2 in the mixed venous blood (PvCOCO2) was calculated from the rise of the CO2 percent in a Grollman bag during rebreathing. In the rest experiments the partial pressure of CO2 in arterial blood (PaCOCO2) was obtained from analysis of alveolar samples taken by the Haldane-Priestley direct sampling method. In the work experiments the PaCOCO2 was calculated using the Bohr formula and a dead space estimated from Asmussen and Nielsen's data. The metabolic rate including both O2 uptake and CO2 output was determined by the Douglas bag method. In each experiment the acetylene method as described by Christensen was applied after the CO2 rebreathing method. The values obtained by the two methods were almost identical, the standard deviation for all experiments being ±7.3%, and were of the same magnitude as those obtained by others with the dye-dilution or direct Fick method both during rest and work. cardiac output at rest and work; arterial Pco2 and venous Pco2 at rest and work; stroke volume at rest and work Submitted on November 25, 1964

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