Refrigerated Platelets for the Treatment of Acute Bleeding: A Review of the Literature and Reexamination of Current Standards: Reply.

Abstract

Reply The authors would like to thank Dr. Valeri and Ms. Giorgio for their thoughtful response to our article, “Refrigerated Platelets for the Treatment of Acute Bleeding: A Review of the Literature and Reexamination of Current Standards” (1), which we read with great interest. We are familiar with the impressive body of work by Dr. Valeri et al. (2, 3) regarding frozen platelets and with the subsequent Netherlands and Australian military clinical experiences (4, 5). We agree with the authors that frozen platelets in dimethyl sulfoxide appear to be both efficacious and safe, although the product has not been fully evaluated by the US Food and Drug Administration (FDA) and it is not approved for use in the United States. The review article in question was published in a Shock supplement containing articles generated by presenters at the Hemostasis and Oxygenation Research Network (THOR) symposium on remote damage control resuscitation, a conference that focuses on solutions for military and civilian patients with severe traumatic hemorrhage in the prehospital and hospital settings. Our laboratory, the Coagulation and Blood Research program at the US Army Institute of Surgical Research, presented data related to our efforts to characterize refrigerated platelets and their potential utility for severely hemorrhaging military casualties in far forward and prehospital environments (1, 6). As suggested by the title of our review article, our intent was not to exhaustively review all potential platelet products but to specifically provide the history and current regulatory status of refrigerated platelets in the United States and the rationale for studying their use in severely bleeding trauma patients. There are several reasons that prompted the focus of this review. The military is tasked with providing FDA-approved solutions for deployed military patients whenever possible. Unlike frozen platelets, refrigerated platelets are currently allowed by the FDA Code of Federal Regulations (7). Our in vitro data suggest that refrigerated platelets, whether as concentrates or in refrigerated whole blood, are both efficacious and safe and may be superior to standard room temperature–stored platelets for controlling hemorrhage (6, 8). These findings are further supported by previously published randomized controlled clinical trials evaluating refrigerated platelets as both concentrates and as an element of cold-stored whole blood (8–10). Furthermore, refrigerated platelets may be the only viable solution in deployed settings with limited logistical capabilities or when infectious disease risk limits on-site fresh whole-blood or platelet collection. Although some far forward hospitals and treatment facilities will not have −80°C freezer capacity, almost all will have the ability to refrigerate platelets. Even transport vehicles can carry “golden-hour box” coolers that can maintain platelets at 4°C. In short, platelets are lifesaving in the setting of severe hemorrhage, and military physicians at Role 2 facilities and forward may not have any other platelet product available. Although maintaining an inventory of multiple platelet products would be ideal, the primary objective is to have at least one viable and safe platelet product for treating severely bleeding servicemen and servicewomen in far forward deployed settings. Heather F. Pidcoke LTC Andrew P. Cap US Army Institute of Surgical Research San Antonio, Texas