TRANSFUSION OF PLATELETS
a. Indications for Platelet Transfusion.
(1) The decision whether to transfuse platelets depends upon the clinical
condition of the patient, the cause of the thrombocytopenia, the platelet count, and the
functional ability of the patient's own platelets (see Table 3-1). Patients with transient
thrombocytopenia from chemotherapeutic treatment of malignancy form the largest
group of patients receiving platelet transfusions. There is little risk of spontaneous
hemorrhage in these patients when the platelet count is over 30,000/mm3. Although
there is some disagreement as to the value of prophylactic platelet transfusion, many
physicians advise platelet transfusions to prevent serious bleeding in these patients
when the platelet count is less than 20,000/mm3.
Platelets useful in treating hemorrhage
(for example, leukemia, hypopastic, or
and for prophylaxis to prevent bleeding
Immune thrombocytopenia purpura
Platelets of little value because of rapid
(for example, ITP)
destruction in the spleen.
Dilutlonal thrombocytopenia (for example,
Platelets of value in replacement (usually
massive transfusion with bank blood)
after 15 to 20 units transfused)
Disseminated intravascular coagulation
Platelets of value only when combined
with efforts to stop DIC or treat the
Functional platelet abnormalities
Platelets from normal donors may Achieve
hemostasis during hemorrhage, surgery,
and dental extractions
Table 3-1. Thrombocytopenia and platelet therapy.
(2) In patients with immune thrombocytopenic purpura, transfused platelets
usually have a very short survival and, thus, may not be helpful. However, platelet
transfusion may be effective in controlling serious active bleeding, especially in surgery.
The most effective forms of treatment may be corticosteroids or splenectomy.
(3) In patients with thrombocytopenia secondary to drug idiosyncrasy, the
offending drug should be discontinued and the patient closely observed. Because
transfused platelets will have a shortened survival, they are advisable primarily for
treatment of active hemorrhage.