Blood, Electrolytes, and Intravenous Infusions

3-16. PRODUCTS FOR TRANSFUSION

Sodium chloride solution (normal saline) is the only solution suitable for use in the transfusion of blood products containing red blood cells, platelets, or leukocytes. Any other solution causes adverse effects on the body and/or blood product. There are three general categories of products used for transfusion-products containing red blood cells, plasma products, and plasma expanders.

a. Red Blood Cell Products. Red blood cell products generally require type and cross-match laboratory procedures. Examples of these are:

(1) Whole blood (human). Whole blood is anticoagulated blood from which none of the components have been removed. Acute significant hemorrhage is the only indication for whole blood in medical patients. Traditionally, whole blood has been used to replace blood loss at surgery. This use is gradually changing to the use of packed red blood cells and a balanced saline solution.

(2) Packed red blood cells. Packed red blood cells have 75 percent of the plasma removed in the laboratory. This preparation is frequently used where the patient needs the oxygen-carrying capacity of the erythrocytes, but would not benefit from the extra fluid or the small amount of protein in the plasma. In many chronic diseases, a further expansion of the plasma volume can cause heart failure. The packed red blood cells also tend to cause less plasma transfusion reactions from donor antibodies. It is safer to use type O Negative packed red blood cells than whole blood when there is no time for cross-match.

b. Plasma. Plasma (or other blood fraction) products are made either from whole blood or from some other process that leaves part of the blood behind. Some examples of these are:

(1) Whole plasma. Whole plasma may be a by-product from the preparation of packed red blood cells, made from blood a few days before the expiration date on the blood unit or drawn by plasmapheresis. Plasma is used as fluid replacement caused by hemorrhage, burns, or in other situations where blood volume must be increased without replacement of blood proteins.

(2) Cryoprecipitate. To make cryoprecipitate, fresh frozen plasma (FFP) is first thawed at 4ºC until all ice is melted. Then the cold insoluble fraction of plasma protein is recovered by centrifugation. The product is used for patients with hemophilia. Cryoprecipitate can be stored for two years at -20º C (20 degrees below 0 Celsius).

(3) Platelet rich plasma. Platelet rich plasma is used in the treatment of some forms of malignancy. This product may be effective in controlling serious active bleeding, especially in surgery. Because of the short survival rate of platelets, the product has limited use. A-B-O group type match is required. No cross-match of other factors is required prior to platelet transfusion unless the platelet product contains many red blood cells. This does not apply to the platelet rich plasma since the plasma itself may carry antibodies.

c. Plasma Expanders. Plasma expanders are used to treat or prevent acute and severe fluid loss due to trauma or surgery. These products are usually used instead of whole blood in emergency-situations in which whole blood is not available. Below are examples of plasma expanders.

(1) Normal human serum albumin. Normal serum albumin is a part of whole blood. It is clear, moderately viscous, brownish fluid contains 25 grams of serum albumin in 100 milliliters of product. Because each gram of albumin holds approximately 18 milliliters of water, it is used as a blood volume expander in the treatment of hemorrhage or shock. In this use, the albumin draws fluid into the circulatory system from the surrounding tissues. This product has also been used as a protein replacement in cases where the level of protein in the serum is very low

(for example, in nephrosis). Normal human serum albumin should not be given to dehydrated patients since it draws fluid from the body tissues. If nine-tenths percent, the product may be administered to dehydrated patients if it is necessary. Sodium chloride solution or five percent dextrose solution is administered at the same time. Fortunately, this product is very stable. Therefore, it is not necessary to keep it refrigerated in its liquid state.

(2) Plasma protein fraction (plasmanate). Plasma protein fraction is a sterile solution of stabilized human plasma proteins in nine tenths. Sodium chloride solution. Each 100 milliliters of this product contains approximately five grams of protein. This product is nearly colorless (slightly brown). Plasma protein fraction is used in the treatment of nonhemorrhagic shock (that is, shock not associated with loss of whole blood). Side effects associated with this product are uncommon, but they include increased salivation, nausea, and vomiting.

(3) Hetastarch. Balanced electrolyte solution that resembles the composition of the principal ionic constituents of normal plasma. Total dosage and rate of infusion depend on the amount of blood or plasma lost and the resultant hemoconcentration as well as age, weight, and clinical condition of the patient. Generally no more than 1L of Hextend (hetastarch in lactated Ringer's solution) should be given. Side effects include systemic overload, and it can inhibit the clotting processes.