Oxygen transfusion

Despite its greater density, oxygen transfuses through a caoutchouc membrane some 2 times as rapidly as nitrogen 3 and a rough separation of the gases from ordinary air can be effected in this manner (see p. 13). 

Whole blood is seldom used ia modem blood transfusion. Blood is separated into its components. Transfusion therapy optimizes the use of the blood components, using each for a specific need. Red cell concentrates are used for patients needing oxygen transport, platelets are used for hemostasis, and plasma is used as a volume expander or a source of proteins needed for clotting of the blood. 

Red Blood Cells. Red blood cells (RBC) transport and deUver oxygen and carbon dioxide between the tissues and lungs. Red blood cell transfusions iacrease the oxygen carrying capacity ia anemic patieats. 

Hamilton RG, Kelly N, Gawryl MS, et al. Absence of immunopathology associated with repeated IV administration of bovine Hb-based oxygen carrier in dogs. Transfusion 2001 41 219. 

Izumi Y, Sakai H, Kose T, et al. Evaluation of the capabilities of a hemoglobin vesicle as an artificial oxygen carrier in a rat exchange transfusion model. ASAIO J 1997 43 289. 

Blood Substitutes. Researchers in lapan (Fukushima Medical Center) and in other institutions in Europe and North America have been investigating substances that, in major characteristics, may serve as a substitute for blood, particularly in emergency situations where rare blood types are not immediately available to severely ill patients who require transfusions. For example, in early 1979, a lapanese patient with a rare O-negative blood was given an infusion of one liter of a new, oxygenated perfluorocarbon emulsion. This compound carried oxygen through the patient s circulatory system until the rare blood could be obtained. 

Broad-spectrum antibiotics may be required to treat infection, 24% oxygen should be given at 4 L/min. Fluids should be given to maintain hydration, orally if possible. Blood transfusion may be considered. 

Hyperbaric oxygenation (HBO) can be a treatment for exceptional loss of blood. HBO may be used on medical or religious grounds medically, if there is a threat of blood product incompatibility or concern of transmissible disease, religiously where belief prohibits the use of transfused blood. 

For endurance sports to enhance the oxygen carrying capacity of the blood (bicycling, marathon running) erythropoietin, blood doping (the athlete has blood withdrawn and stored, then transfused once the deficit had been made up naturally, so raising the plasma haemoglobin above normal). 

Surprisingly, individuals with hemoglobin levels as low as 20 to 30 mg Hb/ml can continue to be physically active. This is due to adaptive mechanisms involving an increase in the heart rate and an increase in efficiency of extraction of oxygen from the blood. Experiments with rats have revealed that the decreased work capacity of the iron-deficient animals, as determined by their ability to run, was due to a deficiency in the enzymes of the respiratory chain of muscle, as well as to anemia. In short, transfusion with normal blood failed to restore fully the running capacity of the deficient animals. 

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