Blood, oxygen content

In practice, tissue perfusion is more important than blood oxygen content in ensuring that aerobic metabolism can continue. 

A. Symptoms and signs are caused by decreased blood oxygen content and cellular hypoxia and include headache, dizziness, and nausea, progressing to dyspnea, confusion, seizures, and coma. Even at low levels, skin discoloration ( chocolate cyanosis ), especially of the nails, lips, and ears, is striking. 

It is important to note that oxygen bound to hemoglobin has no effect on the P02 of the blood. The amount of oxygen bound to hemoglobin determines oxygen content of the blood. The POz of the blood is determined by the amount of oxygen dissolved in the plasma. 

Figure 9.15 presents an example of the in vivo measurements of the oxygen content in the arterial blood of dogs over a period of 10 h. The dots represent the batch gas analysis performed with a Nova Biomedical blood gas analyzer. The solid lines represent the analyses monitored by the instrument. Blood oxygen measurements were obtained continuously (not shown in the figure) about every 3 sec. Two different polymer solutions are shown. The measurements performed by the instrument are not affected by the presence of unmetabolized clots and/or anesthetics in the blood stream. Additionally, no deterioration of the signal was found after 10-h periods. 

The treatments nsed to improve the brain s oxygen supply include vasodilators, anticoagulants, and raising the oxygen content of the blood. Vasodilators work by dilating arteries. When the arteries supplying the brain are opened wide, the plaques of atherosclerosis are less likely to block blood flow. Vasodilators including papaverine, cyclandelate, isoxsuprine, vincamine, and cinnarizine have all been tried. 

Finally, hyperbaric oxygen treatments have also been used to increase the oxygen content of blood. In this way, a smaller amount of blood flowing to the brain might still provide an adequate supply of oxygen. 

Let A be the total membrane area (m ) and dA an infinitesimal increase of A in the blood flow direction. Oxygen saturation y (-) and oxygen partial pressure p (mmHg) increase by dy and Ap, respectively, in the membrane area cL4. The increase in the oxygen content of blood cLV (cm cm rnin ) on dA is given by... 

The average oxygen content of arterial blood is approximately 0.25 g of 02 per liter. Assuming a body temperature of 37°C, how many moles of oxygen are transported by each liter of arterial blood How many milliliters ... 

Low oxygen content in capillary blood, scattered thickening of lungs (as observed in chest radiograms), and upper respiratory irritation have been observed in studies of workers exposed intensely or chronically to molten silver or silver dusts (Forycki et al. 1983 Rosenman et al. 1979, 1987). Inhalation exposure also led to decreased red blood cell count and an increased mean corpuscular volume (Pifer et al. 1989). However, these potential hematologic biomarkers are not specific for silver exposure, and do not indicate or predict significant clinical sequelae. 

You may have heard of hyperbaric oxygen (HBO) chambers being used to treat sports injuries. A high oxygen concentration in the blood causes blood vessels to constrict. This lowers the swelling that can occur in injured tissues. How is this high oxygen content delivered to the blood ... 

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