McKinley et al1 have provided an article of considerable interest, not with respect to the purported sex difference in resuscitation but with reasonably decent data on the factitious anemia of crystalloid resuscitation.
For practical purposes, the mean hemoglobin level at admission for the 58 patients was approximately 10 g/dL; this target was set and maintained throughout the resuscitation process. There were no data for observed or estimated bleeding, yet patients received on average 16 or 17 units of packed red blood cells and 25 L of Ringer lactate solution. Because two thirds of the administered crystalloid fluid leaves the vascular compartment promptly in these circumstances, the resulting intravascular retention of 3000 mL of packed red blood cells and 8000 mL of Ringer lactate solution would have a hematocrit of slightly less than 30. One could estimate from this that blood loss averaged 1500 mL, or 3 units of whole blood.
Lyons WS. Crystalloid Resuscitation: A Waste of Blood?. Arch Surg. 2003;138(2):227. doi:10.1001/archsurg.138.2.227-a