scholarly journals The Oxygen Dissociation Curve of Blood in COVID-19

2021 ◽  
Author(s):  
Dieter Böning ◽  
Wolfgang M. Kuebler ◽  
Wilhelm Bloch
Keyword(s):  
Oxygen Affinity ◽  
The Body ◽  
Oxygen Dissociation Curve ◽  
Dissociation Curve ◽  
Left Shift ◽  
Oxygen Dissociation ◽  
Concomitant Reduction ◽  
Injured Lung ◽  
Concentration Changes

COVID-19 hinders oxygen transport to the consuming tissues by at least 2 mechanisms: In the injured lung saturation of hemoglobin is compromised, in the tissues an associated anemia reduces the volume of delivered oxygen. For the first problem increased hemoglobin oxygen affinity (left shift of the oxygen dissociation curve ODC) is of advantage, for the 2nd, however, the contrary is the case. Indeed a right shift of the ODC has been found in former studies for anemia caused by reduced cell production or hemolysis. This resulted from increased 2,3-biphosphglycerate (2,3-BPG) concentration. In 3 investigations in COVID-19, however, no change of hemoglobin affinity was detected in spite of probably high [2,3-BPG]. The most plausible cause for this finding is formation of methemoglobin, which increases the oxygen affinity and thus apparently compensates for the 2,3-BPG effect. But this "useful effect" is cancelled by the concomitant reduction of functional hemoglobin. In the largest study on COVID-19 even a clear left shift of the ODC was detected when calculated from measurements in fresh blood rather than after equilibration with gases outside the body. This additional „in vivo" left shift possibly results from various factors (e. g. concentration changes of Cl-, 2,3-BPG, ATP, lactate, nitrocompounds, glutathione, glutamate, because of time delay between blood sampling and end of equilibration, or enlarged distribution space including interstitial fluid and is useful for O2 uptake in the lungs. Under discussion for therapy are the affinity-increasing 5-hydroxymethyl-2-furfural (5-HMF), erythropoiesis stimulating substances like erythropoietin, and methylene blue against MetHb formation.

scholarly journals Hemoglobin Non-equilibrium Oxygen Dissociation Curve

2020 ◽  
Author(s):  
Rosella Scrima ◽  
Sabino Fugetto ◽  
Nazzareno Capitanio ◽  
Domenico L. Gatti
Keyword(s):  
Partial Pressure ◽  
Correct Diagnosis ◽  
Oxygen Affinity ◽  
Oxygen Dissociation Curve ◽  
Dissociation Curve ◽  
High Affinity ◽  
Oxygen Dissociation ◽  
Sequential Binding ◽  
Non Equilibrium

AbstractAbnormal hemoglobins can have major consequences for tissue delivery of oxygen. Correct diagnosis of hemoglobinopathies with altered oxygen affinity requires a determination of hemoglobin oxygen dissociation curve (ODC), which relates the hemoglobin oxygen saturation to the partial pressure of oxygen in the blood. Determination of the ODC of human hemoglobin is typically carried out under conditions in which hemoglobin is in equilibrium with O2 at each partial pressure. However, in the human body due to the fast transit of RBCs through tissues hemoglobin oxygen exchanges occur under non-equilibrium conditions. We describe the determination of non-equilibrium ODC, and show that under these conditions Hb cooperativity has two apparent components in the Adair, Perutz, and MWC models of Hb. The first component, which we call sequential cooperativity, accounts for ∼70% of Hb cooperativity, and emerges from the constraint of sequential binding that is shared by the three models. The second component, which we call conformational cooperativity, accounts for ∼30% of Hb cooperativity, and is due either to a conformational equilibrium between low affinity and high affinity tetramers (as in the MWC model), or to a conformational change from low to high affinity once two of the tetramer sites are occupied (Perutz model).

Oxygen dissociation curve for chorioallantoic capillary blood of chicken embryo

1976 ◽  
Vol 40 (3) ◽  
pp. 393-398 ◽  
Author(s):  
H. Tazawa ◽  
T. Ono ◽  
M. Mochizuki
Keyword(s):  
Oxygen Affinity ◽  
Capillary Blood ◽  
Oxygen Dissociation Curve ◽  
Dissociation Curve ◽  
Oxygen Dissociation ◽  
Oxygen Capacity ◽  
Bohr Factor ◽  
Hill’S Equations ◽  
Dissociation Curves ◽  
Clear Relation

Oxygen dissociation curves for blood in the chorioallantoic capillary of chicken embryos were determined using a microphotometric apparatus made for measuring the reaction velocity of a red blood cell with oxygen and carbon monoxide. The modified Hill's equations expressing the dissociation curve during development were calculated by two methods. P50's at pH of 7.4 were found to be 60.0, 54.4, 46.2, 33.1, and 28.6 mmHg for 10, 12, 14, 16 and 18 days of incubation, respectively. Although the Bohr factor did not show a clear relation to age, the oxygen affinity and the oxygen capacity tended to increase with the lapse of days, and the power of heme-to-heme interaction, to decrease with age. The findings imply that there is a respiratory adaptation of embryos during development.

In vivo Blood Oxygen Dissociation Curve of Newborn Infants

Neonatology ◽  
1965 ◽  
Vol 8 (5-6) ◽  
pp. 241-252 ◽  
Author(s):  
W. Oh ◽  
R.A. Arcilla ◽  
J. Lind
Keyword(s):  
Newborn Infants ◽  
Blood Oxygen ◽  
Oxygen Dissociation Curve ◽  
Dissociation Curve ◽  
Oxygen Dissociation

The Bohr effect related to blood and erythrocyte pH

1963 ◽  
Vol 205 (2) ◽  
pp. 337-340 ◽  
Author(s):  
Peter Hilpert ◽  
Renate Gislinde Fleischmann ◽  
Doris Kempe ◽  
Heinz Bartels
Keyword(s):  
Oxygen Pressure ◽  
Ph Value ◽  
Oxygen Affinity ◽  
Bohr Effect ◽  
Red Cell ◽  
Oxygen Dissociation Curve ◽  
Dissociation Curve ◽  
Oxygen Dissociation ◽  
Constant Cell ◽  
The Right

The Bohr effect of the blood and the red cell hemolysates of adult and newborn humans, goats and kids, and sheep and lambs were determined and the physiological significance is discussed. Similar determinations were made on blood from an African elephant, yak, camel, Dybowski deer, and llama. The strong displacement to the right of the oxygen dissociation curve which occurs in kids and lambs during the first 5 days of life can be largely explained by a change in the pH value within the erythrocytes. When the oxygen affinity is expressed by the oxygen pressure necessary for half saturation (T50) at a constant cell pH, considerable differences exist between species.

Adaptation to anemia in hemoglobin E-β thalassemia

Blood ◽  
2010 ◽  
Vol 116 (24) ◽  
pp. 5368-5370 ◽  
Author(s):  
Angela Allen ◽  
Christopher Fisher ◽  
Anuja Premawardhena ◽  
Timothy Peto ◽  
Stephen Allen ◽  
...  
Keyword(s):  
Clinical Phenotype ◽  
Oxygen Affinity ◽  
Oxygen Dissociation Curve ◽  
Dissociation Curve ◽  
Asian Countries ◽  
Hemoglobin F ◽  
Hemoglobin E ◽  
Oxygen Dissociation ◽  
Therapeutic Value ◽  
And Function

Abstract Hemoglobin E β thalassemia is the commonest form of severe thalassemia in many Asian countries. Its remarkably variable clinical phenotype presents a major challenge to determining its most appropriate management. In particular, it is not clear why some patients with this condition can develop and function well at very low hemoglobin levels. Here, we demonstrate that patients with hemoglobin Eβ thalassemia have a significant decrease in the oxygen affinity of their hemoglobin, that is an increased P50 value, in response to anemia. This may in part reflect the lower level of hemoglobin F in this condition compared with other forms of β thalassemia intermedia. The ability to right-shift the oxygen dissociation curve was retained across the spectrum of mild and severe phenotypes, despite the significantly higher levels of hemoglobin F in the former, suggesting that efforts directed at producing a modest increase in the level of hemoglobin F in symptomatic patients with this disease should be of therapeutic value.

scholarly journals A Further Extension of the In Vivo Oxygen-Dissociation Curve for the Blood of the Newborn Infant*

1964 ◽  
Vol 43 (4) ◽  
pp. 606-610 ◽  
Author(s):  
Nicholas M. Nelson ◽  
L. Samuel Prod'hom ◽  
Ruth B. Cherry ◽  
Clement A. Smith
Keyword(s):  
Newborn Infant ◽  
Oxygen Dissociation Curve ◽  
Dissociation Curve ◽  
Oxygen Dissociation

The “in vivo“ Foetal Oxygen Dissociation Curve

Neonatology ◽  
1959 ◽  
Vol 1 (2) ◽  
pp. 61-67 ◽  
Author(s):  
Gösta Rooth ◽  
Sven Sjöstedt ◽  
Franco Caligara
Keyword(s):  
Oxygen Dissociation Curve ◽  
Dissociation Curve ◽  
Oxygen Dissociation

scholarly journals Hemoglobin Duarte: (α2β262(E6)Ala→Pro): A New Unstable Hemoglobin With Increased Oxygen Affinity

Blood ◽  
1974 ◽  
Vol 43 (4) ◽  
pp. 527-535 ◽  
Author(s):  
E. Beutler ◽  
A. Lang ◽  
H. Lehmann
Keyword(s):  
Hemolytic Anemia ◽  
Oxygen Affinity ◽  
Hemoglobin Level ◽  
Oxygen Dissociation Curve ◽  
Thromboembolic Complications ◽  
Dissociation Curve ◽  
Oxygen Dissociation ◽  
History Of ◽  
Unstable Hemoglobin ◽  
Β Chain

Abstract A patient with a normal blood hemoglobin level, but with evidence of brisk hemolysis, was found to have an unstable hemoglobin with a left-shifted oxygen dissociation curve. Two sisters of the patient had a history of hemolytic anemia. Both died of thromboembolic complications following splenectomy. Our patient was found to be heterozygous for a new β-chain mutation and β-thalassemia. All of the hemoglobin in his red cells was of the abnormal type, designated hemoglobin Duarte, and was shown to contain proline at the β62 (E6) position instead of alanine.

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