Fig. 4. The range (“window”) of fractional blood volume loss (area between the maximum allowable fractional blood volume loss without [VRem/VBld], and with acute normovolemic hemodilution [VLOSSmax/VBld]), where acute normovolemic hemodilution can obviate erythrocyte transfusion that otherwise would have been necessary to maintain the trigger hematocrits (Ht) of 0.21 and 0.30 had acute normovolemic hemodilution not been used, for initial hematocrit (Ho), as defined by equations 2 and 8.