HYperbaric oxygenation can be defined as the inhalation of oxygen when the surrounding air, oxygen or other gases are at a pressure greater than atmospheric (atmospheric pressure = 760 mm mercury or 14.7 lb per sq. in. at sea level). In clinical practise this means that the patient breathes 100 per cent oxygen while within an air or oxygen environment at greater than atmospheric pressure. When breathing 100 per cent oxygen under hyper¬baric conditions, more oxygen is dissolved in the blood plasma than when able to clump (agglutinate) red cells.
Each antibody can react with only one group of red cells, and are therefore referred to as anti-A, anti-B, etc., antibodies. Red cells of group A, and plasma containing anti-A antibody are said to be 'incompatible'. It is obvious that an antigen and its corre¬sponding antibody would never normally occur together in the same blood. The antigen/antibody composition of the different blood groups is shown in the Table below. It is not difficult to see why A blood, for instance, cannot be given to either group B or group 0 patients: the blood of both these groups contains anti-A antibodies.There are many other blood groups, e.g. M, N, S, P. etc., which are of minor importance in transfusion. The Rhesus system has some special features and is described.
Maintenance of sterility. When the blood is withdrawn from a donor, full sterile precautions are observed. All equipment and bottles are presterilized. Any bacteria which might gain entrance are discouraged from growing by keeping the blood in a refrigerator. Every hospital should possess a special blood bank refrigerator with a built-in alarm system to warm the staff if the temperature rises above 6 °C (42-8 'F) or falls below 2 'V (35-6 °F). All forms of domestic refrigerator used in the wards are unsuitable for this purpose.
Each antibody can react with only one group of red cells, and are therefore referred to as anti-A, anti-B, etc., antibodies. Red cells of group A, and plasma containing anti-A antibody are said to be 'incompatible'. It is obvious that an antigen and its corre¬sponding antibody would never normally occur together in the same blood. The antigen/antibody composition of the different blood groups is shown in the Table below. It is not difficult to see why A blood, for instance, cannot be given to either group B or group 0 patients: the blood of both these groups contains anti-A antibodies.There are many other blood groups, e.g. M, N, S, P. etc., which are of minor importance in transfusion. The Rhesus system has some special features and is described.
Maintenance of sterility. When the blood is withdrawn from a donor, full sterile precautions are observed. All equipment and bottles are presterilized. Any bacteria which might gain entrance are discouraged from growing by keeping the blood in a refrigerator. Every hospital should possess a special blood bank refrigerator with a built-in alarm system to warm the staff if the temperature rises above 6 °C (42-8 'F) or falls below 2 'V (35-6 °F). All forms of domestic refrigerator used in the wards are unsuitable for this purpose.
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