Your patient is a 50 year old male who presents with head trauma. He takes aspirin daily. Neuroimaging demonstrates subdural and subarachnoid hemorrhage. You plan to treat with DDAVP and platelet transfusion. When ordering the platelets you note that, whereas you are used to ordering a platelet “six pack,” the default order is for one unit of single donor platelets (SDP). What’s the difference? Are there advantages to SDP, or is it a case of six of one half dozen of the other?
Platelet concentrates (PC)
-derived from whole blood
-concentrated from multiple donors
-contain 5.5×10^10 platelets in 45-65 ml given as a pool of 6
Single donor Platelets (SCD)
-collected from single donor by apheresis
-contain 3×10^11 platelets in 200ml given as one unit
PC have been standard care since developed in the 1950s. An effort to reduce alloimunization, particularly in chronically transfused individuals, led to the development of apheresis procedures. This allows collection of an adult dose of compatible platelets from a single donor, and have the following benefits:
1) infectious complications: better screening has led to reduced rates of viral transmission (HIV, HBV, HCV, and T-cell lymphotrophic virus) no good mechanism yet exists further reduce septic platelet transfusion reactions (SPTR). “SPTR are the most common serious infectious risk of transfusion today” in the US and are attributed to contamination from donors skin flora or from donors with asymptomatic bacteremia. In the study referenced SPTR was five times higher in recipients of PC vs SDP transfusion.
2,3) transfusion reaction rate & universal leukodepletion: current apheresis technique allows leukoreduction at time of collection which can reduce cytokine accumulation and febrile reactions
4) reduction of transfusion frequency in pateints with bone marrow suppression: SDP administration gives a large dose and decreased risk for repeat transfusion in the short term
5)prevention of alloimmunization: SDP exposes recipients to only a single donor, and allows universal leukoreduction as above and is beneficial to limit the chance of alloimmunization.
References:
Ness, Paul M., and Sally A. Campbell-Lee. “Single Donor versus Pooled Random Donor Platelet Concentrates.”Current Opinion in Hematology 8.6 (2001): 392-96. Pubmed.gov. Web. 17 Aug. 2015.
