b. Red Cell Products.
(1) Whole blood. Whole blood (WB) is the product of choice for acute
massive blood loss in many hospitals. Others prefer to use colloid or crystalloid
solutions followed by RBC. In acute massive blood loss, the blood volume deficit is as
important as the loss of blood cells and transfusion therapy must replace this volume
deficit. Whole blood may be required for certain special circumstances, such as
exchange transfusion; however, exchange transfusion can be performed with RBC and
either albumin or fresh frozen plasma.
Red Blood Cells.
(a) Red blood cells are the product of choice to restore or maintain
oxygen-carrying capacity. Patients who have chronic anemia, congestive heart failure,
or are elderly or debilitated tolerate poorly, rapid changes in blood volume. Transfusing
RBC increases oxygen-carrying capacity with minimal expansion of blood volume.
Nonhemolytic transfusion reactions occur less frequently after transfusion of RBCs than
after WB, probably because most platelets, granulocytes, and plasma are removed.
(b) The use of RBC in surgery is more controversial. Some surgeons
and anesthesiologists feel that the blood loss that occurs during surgery is acute and
should be replaced with WB. Other surgeons, anesthesiologists, and most
immunohematologists believe that surgical blood loss usually occurs under controlled
conditions can be replaced with RBCs and saline. Investigations have shown no
increased morbidity or mortality from the use of RBC, and this practice is common in
many hospitals. In addition a number of studies have shown that 1,000 to 1,200 ml of
operative blood loss can be replaced by electrolyte and/or colloid solutions without the
use of RBCs. Thus, the loss of two units of blood during "routine" surgery could be
replaced with RBCs. The use of RBCs allows platelet concentrate and plasma products
to be produced from the same unit of blood. Because this is a much more efficient use
of the original unit of blood, RBCs are always preferred, unless there is a specific
indication for the use of WB.
Fresh whole blood.
(a) An order for fresh blood must be interpreted by the blood bank staff
as a cry for consultative help since the uses of fresh blood are often misunderstood by
the patient-care physician. Some patients may have a RBC or blood volume deficit
combined with depletion of functional platelets and/or decreased levels of coagulation
Factors V and VIII; however, it is difficult to replace these deficiencies using fresh WB
because of the volume required. Patients who are thrombocytopenic usually require
more platelets than are present in one unit of blood. Thus, platelet
concentrations should be used. Deficiency of coagulation factors is usually better
managed with cryoprecipitate, fresh-frozen plasma, or concentrated coagulation factors
than with fresh WB.