Association of gender and lowest hematocrit on cardiopulmonary bypass with acute kidney injury and operative mortality in patients undergoing cardiac surgery.

Hemodilution on CPB is a hotly debated topic. Today, transfusion management programs have emerged as a way to reduce the need for allogeneic RBC transfusions but debate over what the safest lowest hematocrit is for cardiac surgery patients persists.  What I found most interesting about this article is that is suggests that women tolerate a lower hematocrit than males. Is this a hormonal protective process or are women pre-conditioned to tolerating lower hematocrits? Certainly for me it has put what I have always practiced into question.  Much work has been done with both lowest hematocrit levels and the deleterious effects of transfusions. I will be eager to see new data regarding this controversial topic as it emerges.