Fecal blood loss: A quantitative method of evaluating hemostasis in patients with thrombocytopenia.

Background: The purpose of our studies was to determine if fecal blood loss can provide a quantitative measure of bleeding at platelet counts of 20 000/μL or less in patients with hypoproliferative thrombocytopenia and to document the effects of different prophylactic platelet transfusion triggers on fecal blood loss.

Methods And Materials: Patients had an aliquot of their autologous red blood cells (RBCs) labeled with Cr. Following reinjection of their radiolabeled RBCs, all feces and a daily blood sample were collected to determine fecal blood loss per day.

Platelets stored in whole blood at 4°C: in vivo posttransfusion platelet recoveries and survivals and in vitro hemostatic function.

Background: Ordinarily, whole blood (WB) is separated into components before storage. We assessed the posttransfusion viability and function of platelets (PLTs) if they were stored within WB at 4°C.

Study Design And Methods: Whole blood was obtained from 30 normal subjects and stored at 4°C without agitation for 12 days and for 10, 15, or 22 days with agitation.

Metabolites in stored platelets associated with platelet recoveries and survivals.

Background: Transfusion of platelets (PLTs) is a common therapy in a number of clinical settings. However, it is well understood that there is substantial donor-to-donor variation in how well PLTs store and thus the quality of the products that are transfused. The basis of such variation is poorly understood, and there are limited metrics by which units of PLTs can be assessed for their posttransfusion performance.

Review of in vivo studies of dimethyl sulfoxide cryopreserved platelets.

A literature review was conducted to assess the efficacy and safety of dimethyl sulfoxide (DMSO) cryopreserved platelets for potential military use. In vivo DMSO cryopreserved platelet studies published between 1972 and June of 2013 were reviewed. Assessed were the methods of cryopreservation, posttransfusion platelet responses, prevention or control of bleeding, and adverse events.

Extended storage of buffy coat platelet concentrates in plasma or a platelet additive solution.

Background: Platelet (PLT) concentrates (PCs) prepared from whole blood in the United States are made using the PLT-rich plasma method. The PCs must be made within 8 hours of blood collection and stored for only 5 days. In Europe and Canada, PCs are made using the buffy coat (BC) method from whole blood held overnight at 22 °C and storage times may be up to 7 days.

Exploratory studies of extended storage of apheresis platelets in a platelet additive solution (PAS).

To evaluate the poststorage viability of apheresis platelets stored for up to 18 days in 80% platelet additive solution (PAS)/20% plasma, 117 healthy subjects donated platelets using the Haemonetics MCS+, COBE Spectra (Spectra), or Trima Accel (Trima) systems. Control platelets from the same subjects were compared with their stored test PAS platelets by radiolabeling their stored and control platelets with either (51)chromium or (111)indium. Trima platelets met Food and Drug Administration poststorage platelet viability criteria for only 7 days vs almost 13 days for Haemonetics platelets; ie, platelet recoveries after these storage times averaged 44 ± 3% vs 49 ± 3% and survivals were 5.

Platelet concentrates prepared after a 20- to 24-hour hold of the whole blood at 22°C.

Background: The Food and Drug Administration (FDA) requires that red blood cells must be refrigerated within 8 hours of whole blood collection. Longer storage of whole blood at 22°C before component preparation would have many advantages.

Study Design And Methods: Two methods of holding whole blood for 20 to 24 hours at room temperature were evaluated, refrigerated plates or a 23°C incubator.

A randomized controlled trial comparing autologous radiolabeled in vivo platelet (PLT) recoveries and survivals of 7-day-stored PLT-rich plasma and buffy coat PLTs from the same subjects.

Background: A recent review concluded that there was inadequate evidence to show a difference between buffy coat (BC) and platelet (PLT)-rich plasma (PRP) PLT concentrates prepared from whole blood. We hypothesized that 7-day-stored BC-PLTs would have superior autologous recoveries and survivals compared to PRP-PLTs and that both would meet the Food and Drug Administration (FDA) criteria for poststorage viability.

Study Design And Methods: This was a randomized, crossover study design in healthy subjects who provided informed consent.

Extended storage of platelet-rich plasma-prepared platelet concentrates in plasma or Plasmalyte.

Background: Using bacterial detection or pathogen reduction, extended platelet (PLT) storage may be licensed if PLT viability is maintained. The Food and Drug Administration (FDA)'s poststorage PLT acceptance guidelines are that autologous stored PLT recoveries and survivals should be 66 and 58% or greater, respectively, of each donor's fresh PLT data.

Study Design And Methods: Nonleukoreduced PLT concentrates were prepared from whole blood donations.

Effects of pretransfusion warming of platelets to 35 degrees C on posttransfusion platelet viability.

Background: Three of four prior studies suggested that warming platelets (PLTs) to 37 degrees C before transfusion into patients with thrombocytopenia gave improved corrected PLT count increments.

Study Design And Methods: Eighteen normal subjects had apheresis PLTs collected that were stored at 22 degrees C for 5 days in two storage bags. One bag of PLTs was warmed to 35 degrees C before infusion, and one remained at 22 degrees C.

Viability and function of 8-day-stored apheresis platelets.

Background: Methods of bacterial detection and pathogen inactivation of platelets (PLTs) may allow extended storage of PLTs as long as PLT quality is maintained.

Study Design And Methods: Twenty normal volunteers had their PLTs collected with an apheresis machine (Haemonetics Corp.).