c. Granulocyte Transfusions. Special instruments have been developed that
make granulocyte collection possible. Transfused granulocytes function normally and,
in selected patients, produce clinical benefits. Patients with profound neotropenia or
chronic granulomatous diseases are likely to receive granulocyte transfusions.
Granulocyte transfusions have not been proven effective in patients with localized
infections or infections with agents other than bacteria. Those recipients who survive
this acute infection can be expected to have a satisfactory quality of life for a reasonably
long period of time.
d. Opsonins in Stored Blood. Opsonic activity is stable in CPD blood stored
under standard conditions for 28 days. Fibronectin is also stable in stored blood
products. Patients receiving massive transfusions with RBCs, crystalloids, or albumin
solutions may have diminished circulation opsonins. Some personnel have suggested
that raising plasma opsonin levels might be beneficial. However, specific therapeutic
recorrmendations must await controlled clinical studies and further understanding of the
roles of these proteins in health and disease.
ADMINISTRATION OF BLOOD PRODUCTS
Once a blood transfusion has been ordered, the procedure should be
explained to the patient in order to minimize his apprehension. The following
steps are important to ensure a safe and efficient transfusion.
a. Obtaining the Sample To Be Used For Compatibility Testing. See
Lesson 1, Section IV, Determination of Compatibility.
b. Blood Administration Sets.
(1) Red blood cells, platelets, granulocytes, fresh-frozen plasma, and
cryoprecipitate should be administered through a filter because fibrin clots and other
particulate debris may be present. Most standard blood and platelet filters have a pore
size of approximately 170 to 260 micrometers, but there is some variation in the surface
area of the filter and the arrangement of the filter and drip chamber. Filters with a larger
surface area may allow more rapid infusion of RBCs because, although the pore size is
the same, there is more filtration area. The filter chamber should be filled with blood in
order to utilize all this surface area. The frequency with which filters should be changed
depends upon the type of blood product being infused and, if RBCs are involved, the
age of the product. As debris accumulates on the filter, the rate of infusion is slowed.
In addition, platelets may adhere to the debris on the filter.
(2) A single filter can usually be used for administration of 2 to 4 units of
RBCs. Because of the hazards of hemolysis and bacterial contamination, once a filter
has been used and contains blood or debris, it should not be left for extended periods
and then reused.