Monitoring for Refractoriness to Platelet Transfusion
➤ UPDATED. Although there are no empirical data to suggest that
monitoring and acting on the post-platelet-transfusion count decreases
the incidence of hemorrhagic events, the Panel consensus is that
platelet counts done 10–60 minutes posttransfusion should be obtained
after all transfusions, when refractoriness is suspected. Because
patients may have a poor increment to a single transfusion yet have
excellent platelet increments with subsequent transfusions, a diagnosis
of refractoriness to platelet transfusion should only be made when
at least two transfusions of ABO-compatible units, stored <72 hours,
result in poor increments, as defined in the supporting text of the
recommendation. (Moderate Recommendation; IC-Ins)
Managing Refractoriness to Platelet Transfusion
➤ Alloimmunization is usually due to antibody against HLA antigens and
only rarely to platelet specific antigens. Patients with alloimmune
refractory thrombocytopenia, as defined above, are best managed with
platelet transfusions from histocompatible donors matched for HLA-A
and HLA-B antigens. Many blood suppliers have access to computerized
lists of such donors. For patients (a) whose HLA type cannot be
determined, (b) who have uncommon HLA types for whom suitable
donors cannot be identified, or (c) who do not respond to HLA matched
platelets, histocompatible platelet donors can often be identified
using platelet cross-matching techniques. In many patients, these two
techniques are complementary. (Strong Recommendation; EB-H)
