All blood components must be transfused using transfusion tubing that has an inline filter. This filter helps removes clots, platelet clumps, and debris, etc. There are other filters that filter out WBCs, but those are not usually used at bedside. They are used during the manufacturing of blood components. So basically, all standard blood component transfusions to patients requires a filter.
So it is safe to give blood components to patients before identifying the antigens? No. You would need to know at the least the ABO/Rh antigens of the blood component before you can give it to any patient.
Good luck.
TIPS For transfusing.pdf