When he got started in blood banks almost 20 years ago, David R. Green's understanding of the blood-transfusion process wasn't very sophisticated. Green, now the president and CEO of the Mississippi Valley Regional Blood Center, had a background in finance.

"I thought they simply took that bag of blood after they tested it and made sure that it was hanging above the patient, and it just flowed back in the patient," Green said last week. "I really didn't know."

Now Green runs an organization that last year collected more than 133,000 units of blood products, serves 53 hospitals in four states, and had more than $38 million in revenue in 2008. The organization's 72,000-square-foot building off 53rd Street in northeastern Davenport suggests a big operation, but few people realize just how large, or the complexity of the issues the blood-donation community deals with.

"The core of it is making sure the donors are safe, and that the product that goes out the back door is safe for recipients," said Dr. Louis Katz, the center's executive vice president for medical affairs.

The Mississippi Valley Regional Blood Center is trying to optimize - and therefore drive down - blood usage by hospitals; it is working to help identify heretofore poorly understood risks associated with blood transfusion; and Katz is among those preparing for the next disease threat to the blood supply. And the organization's size has the key benefit of keeping costs lower for local hospitals.

So it's not just bags of blood.