LESSON 3
BLOOD TRANSFUSION
Section I. BLOOD TRANSFUSION PRACTICE
3-1.
BACKGROUND
The development of methods for preserving RBCs and other blood components
has made transfusion readily available. Despite the relative ease of transfusion, it may
have serious complications and should be undertaken only after considering the
etiology and course of the patient's disease and clinical condition. If transfusion therapy
is indicated, the specific blood traction that is lacking should be identified, and a specific
blood component used to replace that deficit. Usually the patient is best served when
specific blood component therapy is utilized.
3-2.
TRANSFUSION OF BLOOD PRODUCTS CONTAINING RED BLOOD CELLS
a. Indications for Transfusion of Red Blood Cells (Human) and Whole
Blood (Human).
(1) The most common reasons for transfusion are replacement of RBCs for
oxygen-carrying capacity or restoration of blood volume. In deciding whether a patient
requires RBC transfusion, the clinical condition of the patient is of primary importance.
The amount of blood loss that can be tolerated without replacement depends upon the
condition of the patient. If blood loss has been acute, the patient may have normal or
nearly normal hemoglobin, but may, nevertheless, require transfusion for the restoration
of blood volume. If blood loss is judged sufficient to require transfusion, it is not
necessary to wait until symptoms such as pallor, diaphoresis, tachycardia, or
hypotenslon develop. On the other hand, transfusion should not be initiated too rapidly
because it seems clear that, in most normal "patients," the loss of approximately 1,000
ml can be replaced by colloid or crystalloid solutions alone.
(2) When anemia has developed over a long period of time, the patient
adjusts to lower hemoglobin levels and may not require transfusion despite very low
hemoglobin levels. The condition of the patient is of primary importance, not the
laboratory values. There is no evidence that it is necessary to transfuse a patient to a
"normal" hemoglobin prior to surgery, nor is there any specific hemoglobin value above
that patients feel better or wound healing is improved. In patients with chronic anemia,
attempts should be made to diagnose and treat the anemia. Transfusion should be
used only as a last resort since it may suppress erythropoiesis.
MD0846
3-2