Partial blood oxygen

The use of oxygen in pediatric incubators is an important factor in increasing the survival rate of premature infants who develop cyanosis. However, the use of oxygen is associated with risk of developing the visual defect known as retrolental fibroplasia (38). A careflil monitoring of arterial blood oxygen partial pressure is important. 

Intracorporeal oxygenators are an entirely different type of blood oxygenator that can be used within the body to temporarily and partially assist the lung functions of patients with serious pulmonary diseases. No blood pump is necessary. 

In the case where the blood flow is laminar, as within hollow-fiber oxygenators, the rates of blood oxygenation can be predicted on a theoretical basis. Due to the shape of the oxyhemoglobin dissociation curve and the fact that the oxygen partial... 

In recent years, many investigations have been conducted, including clinical trials, with bioartificial fiver devices using either animal or human liver cells. Likewise, many reports have been made with various designs of bioartificial fiver device [19]. However, there are no established fiver support systems that can be used routinely in the same way as hemodialyzers or blood oxygenators. Today, bioartificial fiver devices can be used to assist the fiver functions of patients with fiver failure on only a partial and/or a temporary basis. Moreover, none of these devices can excrete bile, as does the human fiver. 

There is some evidence, however, that the potential utility of a tHb as a hemodiluent and tissue-oxygenating solution may be dependent on the structure and properties of that tHb. For example, the results of a study of the effects of partial blood replacement with pyridoxa-lated Hb polyoxyethylene conjugate (PHP) solution (Ajinomoto) in a gerbil model of transient cerebral ischemia suggested that PHP solution holds less promise as a clinical treatment for this type of focal ischemia than does DCLHb.t ]... 

The partial pressure, Pq, of the oxygen in the blood (oxygen tension) is related to Sq by the oxygen dissociation curve (Fig. 2.11). The shape and position of this sigmoidal curve depend on the temperature, the hydrogen ion concentration and the concentration within the red cells of other ligands of haemoglobin... 

CCS, Glasgow Coma Scale CSF, cerebrospinal fluid TBI, traumatic brain injury ABC, arterial blood gas Pa02, partial pressure of arterial blood oxygen PaC02, partial pressure of arterial blood carbon dioxide CT, computed tomography. 

Oxygenation Rate. The progress of blood oxygenation in the glass column was indicated not only by the increase of oxygen partial pressure in blood (Table I and Figures 2 and 3) but also by the change of blood... 

Figure 6 shows the effects of reduced fetal blood volumetric flow rate on the maternal blood axial oxygen partial pressure profile. As fetal blood flow rate decreases and fetal blood oxygen partial pressures increase,... 

Figure 8 shows the effects on the fetal blood axial oxygen partial pressure profile when the maternal blood flow rate is decreased. As the maternal blood flow rate decreases, the fetal profile is shifted downward, resulting in fetal blood oxygen partial pressure values in the fetal capillary that are lower than normal. 

Figure 9. Axial partial pressure profiles in the maternal channel for various maternal blood oxygen capacities...

The effects of decreasing the maternal blood oxygen capacity on the fetal blood axial partial pressure profiles are shown in Figure 10. As the oxygen capacity of maternal blood decreases, the fetal axial oxygen partial pressure profile is shifted downward. 

The fetal blood oxygen partial pressure values in the first half of the fetal capillary increase more rapidly than those in the second half. This results from the large pressure gradient initially present between maternal and fetal streams rather than the slope of the dissociation curve. As the last half of the exchange system is reached, maternal and fetal values approach each other, the gradient is decreased, and the rate of oxygen transfer decreases. 

One of the principal objections centers on the nonlinear calibration curve for the determination of blood oxygen partial pressures. This resulted from the formation of an oxygen-depleted boundary layer near... 

The most widely used application of G - L contactors is in blood oxygenation. In these so-called oxygenators pure oxygen or air is flow at one side of the membrane, most hollow fibers, while the blood flows at the other side. Due to a gradient in partial pressure oxygen will diffuse into the blood and carbon dioxide will diffuse from the blood to gas phase. 

There are respiratory disorders in which the blood oxygen partial pressure falls with insignificant change or even a fall in the partial pressure of carbon... 

Figure 1 Frequency distribution of oxygen partial pressure in tissue under normoxic, hypoxic, and anoxic conditions of the arterial blood. Oxygen sensing provides for all three conditions a response to trigger different cell functions (70).

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