b. Most patients who are not in congestive heart failure or in danger of fluid
overload tolerate the transfusion of one unit of red blood cells in a 1 1/2 to 2 hour
period. One unit of whole blood equals about 500 milliliters (about 450 milliliters of
blood plus 60 milliliters of anticoagulant). The transfusion should be completed in less
than four hours because of the dangers of bacterial growth and red blood cell hemolysis
at room temperature. During the first 15 minutes, the rate of transfusion of red blood
cells should be very slow, about 100 milliliters per hour. This will keep the volume of
red blood cells low in case the patient has an immediate adverse reaction. Watch the
patient attentively during the first five minutes and then check after fifteen minutes. At
that point, the rate may be increased if the physician orders. After the transfusion,
record any adverse reaction and discontinue the intravenous infusion.
3-19. ADVERSE BLOOD PRODUCT REACTIONS
Most adverse transfusion reactions are caused by leukocytes, platelets, and
plasma proteins (since red blood cell antibodies have already been checked). All the
care in cross-matching blood in the laboratory can be negated by administering the
blood to the wrong patient. Always double-check.
a. Immediate Effects. An adverse effect can be either immediate or delayed. If
the effect is immediate and the transfusion reaction involves more than just a reddening
of the skin, the transfusion should be stopped immediately, but the intravenous line
should be kept open.
(1) Congestive heart failure. Congestive heart failure that is caused by
circulatory overload shows up as coughing, cyanosis, and difficulty in breathing. This is
probably the most preventable adverse reaction to transfusion. If a patient is
susceptible to circulatory overload, concentrated red blood cells should be transfused at
no faster than one milliliter per kilogram of body weight per hour.
(2) Febrile reactions. Febrile reactions (fever), often preceded by chills, are
the most common adverse transfusion reactions. These reactions are usually mild and
result mainly in patient anxiety and discomfort. Rarely, there is some infiltration in the
lungs, reduction in the body's white cells, shock, or death. There are variations in blood
products or medications that may lessen febrile complications.
(3) Allergic reactions. Allergic reactions are usually relatively mild. Most
are local skin redness, hives, and itching. These are treated with antihistamines.
Flushing, nausea and vomiting, diarrhea, changes in blood pressure and anaphylaxis
are severe reactions that sometimes require a specially prepared blood product. Some
severe reactions can be treated by antihistamines. Others require epinephrine.
MD0564
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