The safety of blood components and derivatives.

An overview of the steps taken to ensure the safety of blood components and derivatives is provided. A brief discussion of hereditary bleeding disorders (hemophilia A, B, and von Willebrand's disease) is included, and the safety of derivatives available for their treatment is discussed, as well as the method of production and the level of safety of derivatives such as factor VIII and factor IX concentrates.

Health risks to cytapheresis donors.

Platelets and granulocytes collected by cytapheresis techniques are recognized as drugs by the US Food and Drug Administration. Though potentially life-saving, like all drugs or therapeutic modalities they have many side-effects, and untoward reactions occur in recipients. However, unlike any other class of drug, cytapheresis products cause untoward and occasionally serious reactions in humans during their preparation. Since the only source for these medications is healthy, human blood donors we should be doubly certain that we use them with care and for very specific indications. Primum non nocere--first, do no harm--is an old and valuable medical axiom , and it applies to our blood donors as well as to our patients. Careful review of our use of these products and intelligent monitoring of appropriate medical and laboratory data in our donors are absolute necessities that we owe to our patients and our various publics . To do less reduces medical practice to mere technology, a state of affairs already too commonplace.

Rapid thawing of fresh frozen plasma.

Fresh frozen plasma (FFP) normally requires about 45 min to thaw in a 37 degrees C water bath when placed inside an additional plastic overbag. That relatively prolonged time may result in non-utilization or delays in delivery of the product, especially, during emergency surgery. One report recommends the use of a microwave oven to overcome those problems. Most blood banks do not have microwave ovens but usually do have water baths at 56 degrees C. Ten units of FFP thawed inside plastic overbags at 37 degrees C required 49.5 +/- 3.9 min and 22 units thawed at 56 degrees C required 28.3 +/- 4 min to thaw. Removal of the plastic overbag reduces the thawing time to 12-13 min at 56 degrees C. The activity Factor V was 85 +/- 15% (65-106%) at 37 degrees C and 80 +/- 21% (47-118%) at 56 degrees C. Factor VIII activity was 86 +/- 21% (59-118%) at 37 degrees C and 90 +/- 37% (46-225%) at 56 degrees C. There were no demonstrable alterations in fibrinogen, PT, APTT, Factor II, VII, IX, and XI between the two thawing temperatures, even after 24 hours of storage at 4 degrees C.

Immune system changes in cytapheresis donors.

In vitro measurements of several variables of the immune system were made in 21 healthy donors who had been subjected to frequent cytapheresis an a group of whole blood donor controls matched for age and sex. Significant changes noted in the apheresis donors compared to controls included a 23 percent lower mean absolute lymphocyte count (p less than .01), a 25 percent lower mean T cell count (p less than .01), and a 46 percent lower mean B cell count (p less than .001). Serum protein changes included a 27 percent lower mean gamma globulin level (p less than .01), and 14 percent lower mean IgG level (p less than .05) in the apheresis donors when compared to the control group. The possible implications of these findings are discussed, and we suggest that donors undergoing multiple cytapheresis procedures be closely monitored to determine the safe donation frequency.

Antileukocyte antibodies in patients refractory to platelet transfusions.

Sera from 12 multitransfused patients who were refractory to random-donor platelets were tested for lymphocytotoxic and leukoagglutinating antibodies using panel cells from various volunteers whose HLA-A and -B antigens were known. All sera contained leukoagglutinins reactive with cells from at least one panel member, whereas only 33% had lymphocytotoxic antibodies. Patients whose sera reacted frequently with panel cells using the microcapillary agglutination technic seldom responded to HLA-matched paltelets, whereas those whose sera reacted infrequently usually responded satisfactorily. It is concluded that non-HLA antibodies may play a significant role in determining the responses to platelet transfusions in multi-transfused patients.