Maintaining an adequate supply of platelets is laborious and costly since they can only be stored for 5 to 7 days at room temperature and require additional bacterial testing. In the 1960s and 1970s, platelets were stored at 1-6° C, but circulation time of cold-stored platelets is very short and the practice was abandoned in the 1980s. Some studies, however, suggest that cold storage of platelets might actually preserve their hemostatic function and may be best for actively bleeding patients. In order to evaluate the function of platelets stored at colder temperatures compared to standard room temperature platelets, researchers compared platelet contractile forces in vitro, in vivo survival and function of transfused platelets in mice, and platelet aggregation after transfusion in human volunteers. While cold-stored platelets generated similar contractile forces after activation compared to room temperature-stored platelets in vitro, cold-stored platelets had lower levels of glycoprotein VI (GPVI). GPVI binds to collagen and activates platelets. These lower levels of GPVI led to significantly less aggregation of cold-stored platelets compared to standard room temperature-stored platelets after transfusion in eight healthy human volunteers. In addition, the absolute and corrected platelet counts were both significantly lower in transfused cold-stored platelets stored versus room temperature. Further studies should investigate whether these changes affect the clinical function of platelets in actively bleeding patients.
Reference:
