Whole blood: the future of traumatic hemorrhagic shock resuscitation.

Toward the end of World War I and during World War II, whole-blood transfusions were the primary agent in the treatment of military traumatic hemorrhage. However, after World War II, the fractionation of whole blood into its components became widely accepted and replaced whole-blood transfusion to better accommodate specific blood deficiencies, logistics, and financial reasons. This transition occurred with very few clinical trials to determine which patient populations or scenarios would or would not benefit from the change.