For patients >4 months, uncross-matched (or “emergency release”) blood is rarely transfused, because most blood banks can complete an IAT cross-match within 1 hour. In cases of massive, exsanguinating hemorrhage, “type-specific” blood (ABO and Rh[D]-matched only), usually available in 10 minutes, can be used. If this delay is too long (as in severe fetomaternal hemorrhage), type O Rh(D)-negative RBCs should be used.