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FFP and FP24 are usually thawed in a 37°C water bath in an overwrap. However, it takes about 15–20 minutes to thaw one or two units, and someone must occasionally manipulate the unit to speed thawing by breaking up the pieces of ice. This time requirement is a substantial difficulty when FFP is needed for actively bleeding patients. Several approaches have been used, including larger water baths and water baths with agitating trays so that staff members do not need to manipulate the units. Another more promising approach is the use of microwave ovens for thawing FFP [57, 58]. The concern with microwave thawing has been the uneven energy distribution within the unit of FFP and resulting “hot spots” and damage to proteins. As microwave devices have improved, it appears that these problems have been overcome. After thawing, FFP or FP24 can be relabeled as thawed plasma (TP) and stored for up to 5 days at 1–6°C. Upon thawing, factor VIII and protein C levels are lower in FP24 than FFP, but there are adequate coagulation factor activities to maintain hemostatic effectiveness [59]. By day 5, factor V levels are about 60% and factor VIII levels 40–70%. Thus, as a source of coagulation factor replacement, it is best to use the TP within 24–48 hours. Five‐day storage makes it possible to maintain a stock supply of TP for emergency use in massive transfusion or urgent correction of warfarin therapy (see Chapters 10 and 11).