A method to collect, store and issue multiple aliquots of packed red blood cells for neonatal transfusions.

Premature neonates require multiple red blood cell (RBC) transfusions. Single-donor programs have been proposed as a means to limit donor exposures, but methods must be developed to collect, store long-term and issue multiple aliquots of RBCs from a single donor. We evaluated a method by which RBCs could be collected, leukocyte depleted, repeatedly centrifuged for issuance as multiple small aliquots of high-hematocrit cells and then resuspended for continued storage throughout 42 days. The quality of RBCs handled by the method were compared to cells stored in standard fashion. Leakage of intracellular potassium, hemoglobin and lactic dehydrogenase into the extracellular fluid from RBCs processed by either method was comparable-indicating maintenance of RBC integrity. Multiple cultures, taken throughout the period of storage, were sterile to document that extensive handling did not introduce contamination. This new method appears promising as a means to provide RBCs for neonates.

Concurrent comparison of the safety of paid cytapheresis and volunteer whole-blood donors.

BACKGROUND: Historically, paid blood donors were found to transmit hepatitis at higher rates than volunteers. In those older studies, paid donors frequently were recruited from prisons or slum areas--a finding consistent with the belief that monetary payment in itself did not necessarily lead to the high-risk status of commercial blood. Instead, it was the population base from which the donors were recruited that was important. STUDY DESIGN AND METHODS: Today, cytapheresis donors are in great demand. Because payment is one incentive that might entice donors to undertake the increased commitment of repeated cytapheresis donation, the results were studied of infectious disease history and laboratory testing performed concurrently in 917 volunteer whole-blood donors and 1240 paid cytapheresis donors, who were enrolled in distinct programs at the DeGowin Blood Center from October 7, 1987, through November 30, 1990. RESULTS: When first, repeat, and overall donations made by these donors were evaluated separately, paid cytapheresis donors were found to exhibit no increase in infectious disease history or test results beyond those of volunteer whole-blood donors. CONCLUSION: Thus, paid cytapheresis donors, when managed within a formal program, should not necessarily be presumed to be more dangerous than volunteers, from an infectious disease aspect. However, definitive proof of safety (comparison of transfusion-transmitted infection rates in two groups of patients receiving blood components exclusively from either paid cytapheresis or volunteer donors) was not pursued by long-term follow-up studies.

Pentastarch may cause fewer effects on coagulation than hetastarch.

Hetastarch, the currently marketed preparation of hydroxyethyl starch, affects coagulation by prolonging partial thromboplastin, prothrombin, and bleeding times; by lowering clotting proteins such as fibrinogen via hemodilution; by lowering clotting factor VIII (coagulant, von Willebrand antigen, and von Willebrand activity) to a greater degree than can be explained simply by hemodilution (i.e., presumably factor VIII affected by both hemodilutional plus additional, independent effects); and, finally, by shortening thrombin, reptilase, and urokinase-activated clot lysis times. Pentastarch, a new analog of hetastarch, was found to exert lesser effects on blood coagulation, despite its greater hemodiluting properties. When compared with hetastarch, pentastarch had little effect on factor VIII (except that due to hemodilution), shortened thrombin times to a significantly lesser degree, exerted no effect on the urokinase-activated clot lysis time, and did not prolong the bleeding time. Even when plasma hydroxyethyl starch levels were similar, pentastarch seemed to alter the results of coagulation assays to lesser degree than did hetastarch, which suggests the possibility of greater safety. Therefore, pentastarch may be a desirable drug, not only for leukapheresis, but also for plasma volume expansion in trauma and surgical patients who often have additional hemostatic abnormalities that place them at increased risk of hemorrhage.

Selecting the optimal dose of low-molecular-weight hydroxyethyl starch (Pentastarch) for granulocyte collection.

A new, rapidly excreted, low-molecular-weight form of hydroxyethyl starch (Pentastarch), is effective and safe in centrifugation leukapheresis. To define the optimal dose of Pentastarch, 12 subjects donated granulocytes by continuous-flow, centrifugation leukapheresis on three occasions at 3-week intervals. Each subject received approximately 250,500, or 1000 ml of Pentastarch according to a random sequence during procedures in which 81 of donor blood was consistently processed. Plasma Pentastarch concentrations (mean mg/ml) measured immediately after leukapheresis were 3.1, 6.7, and 12.7 for the 250, 500-, and 1000-ml doses, respectively. Total leukocyte and neutrophil yields with the 500- or the 1000-ml doses of Pentastarch were similar, and both were significantly greater (p less than 0.05) than those with the 250-ml dose. Neutrophil yields per concentrate (mean X 10(-10) were 0.74, 1.72, and 1.73 for the 250-, 500-, and 1000-ml doses, respectively. Pentastarch dose had little effect on lymphocyte and platelet yields. No serious adverse effects were evident for any dose of Pentastarch during 12 weeks of observation. In particular, the 1000-ml dose did not produce increased toxicity. Thus, a single 500-ml bottle of 10 percent Pentastarch produced maximal yields; efficacy was not improved by doubling the dose.