No abstract

Fresh-frozen plasma (FFP) and cryoprecipitate both contain Factors I and VIII, however thawed FFP may be stored at 1-6 degrees C for 24 hours, but thawed cryoprecipitate may only be stored at 1-6 degrees C for six hours when used for Factor VIII content. To determine whether it would be safe and effective to extend the storage period of thawed cryoprecipitate from 6 to 24 hours, Factor VIII (and fibrinogen) levels were measured in 25 units of cryoprecipitates immediately on thawing and at 6 hours and 24 hours thereafter. The Factor VIII activity level decreased to 86% of the original activity level within 6 hours, but the drop between 6 and 24 hours was relatively small. Eighty percent of the original activity was still present at 24 hours after thawing. The fibrinogen level decreased to 87% of the original level within 6 hours but remained stable between 6 and 24 hours. Additional testing showed that fibrinogen levels remained stable between 6 and 74 hours. These data suggested that the storage of thawed cryoprecipitate might be extended to 24 hours when this blood product is used for Factor VIII content and to 74 hours when it is used for fibrinogen content. Furthermore, the lack of prohibition on the use of cryoprecipitate that has been thawed for more than six hours and stored at 4 degrees C for its fibrinogen content seems reasonable.

Most transfusion services discard unopened units of blood that have been returned to the blood bank more than 30 minutes after the issuance or have attained a temperature of more than 10 degrees C. The objective of this study was to learn the prevalence of bacterial growth, if any, in the units of blood that were exposed twice, for six hours each time, to room temperature during their refrigerated storage. All of the 396 units cultured were negative except one red cell unit that grew a Bacillus species, probably B. subtilis. Further studies suggested that the growth of B. subtilis was due to laboratory contamination. The authors concluded that more work is needed to study the bacterial growth and the effect on red cell enzymes in the units of blood that are exposed to room temperature for varying periods or are returned to the blood bank after 30 minutes of issuance. If no adverse effect is noted, the policy of not reissuing such units may need revision so that more units could be salvaged.