The effect of variation in donor platelet function on transfusion outcome: a semirandomized controlled trial

Abstract

The effect of variation in platelet function in platelet donors on patient outcome following platelet transfusion is unknown. This trial assessed the hypothesis that platelets collected from donors with highly responsive platelets to agonists in vitro assessed by flow cytometry (high-responder donors) are cleared more quickly from the circulation than those from low-responder donors, resulting in lower platelet count increments following transfusion. This parallel group, semirandomized double-blinded trial was conducted in a single center in the United Kingdom. Eligible patients were those 16 or older with thrombocytopenia secondary to bone marrow failure, requiring prophylactic platelet transfusion. Patients were randomly assigned to receive a platelet donation from a high- or low-responder donor when both were available, or when only 1 type of platelet was available, patients received that. Participants, investigators, and those assessing outcomes were masked to group assignment. The primary end point was the platelet count increment 10 to 90 minutes following transfusion. Analysis was by intention to treat. Fifty-one patients were assigned to receive platelets from low-responder donors, and 49 from high-responder donors (47 of which were randomized and 53 nonrandomized). There was no significant difference in platelet count increment 10 to 90 minutes following transfusion in patients receiving platelets from high-responder (mean, 21.0 × 10/L; 95% confidence interval [CI], 4.9-37.2) or low-responder (mean, 23.3 × 10/L; 95% CI, 7.8-38.9) donors (mean difference, 2.3; 95% CI, -1.1 to 5.7; = .18). These results support the current policy of not selecting platelet donors on the basis of platelet function for prophylactic platelet transfusion.

Evaluation of the in vitro Function of Platelet Concentrates from Pooled Buffy Coats or Apheresis

“…Underlying causes can be patient-associated factors, such as fever, medication, sepsis, or patient anti-PLT antigen (HPA, human PLT antigen) antibodies, or can otherwise be due to the increased consumption of PLTs within the scope of the desired hemostasis [2, 3]. In contrast, PLT refractoriness can be product-related and associated with PLT-inherent functional variations due to the habitual and physiological conditions of the donors [4]. The manufacturing process may also impact PLT functionality [5].…”

Effect of platelet storage duration on clinical outcomes and incremental platelet change in critically ill children

“…28 The differences in these findings may be related to heterogeneity among the recipients or the PLT donors. 29 Fewer studies have been published that explore a similar association in children. Given the differences in physiology and etiologies of critical illness that exist between children and adults, pediatric patients may have different clinical outcomes associated with the storage age of the PLT concentrates.…”

Effect of Pneumatic Tubing System Transport on Platelet Apheresis Units

“…[32, 38, 39] Moreover, recent work by Kelly et al ., showed that the ability of platelet apheresis units to increase platelet count in non-bleeding cancer patients with thrombocytopenia was independent of the degree of platelet function as measured by aggregometry, P-selectin expression and fibrinogen binding. [40] Thus, perhaps as long as patients have a threshold concentration of functional platelets in circulation, the transfusion of additional platelets, even though they may exhibit reduced absolute activity, may be sufficient to stop bleeding. In this setting, the reactivity of the platelets within platelet apheresis units may be secondary to the ability to rapidly transport platelet apheresis units to patients at risk of hemorrhage.…”