The Blood Center of Central Iowa, which supplies 34 hospitals in 33 central and northern Iowa counties, is running low. Normally spokeswoman Christine Hayes says the center tries to keep a five-day supply of blood on hand, but that’s down to less than 2 days right now. The center had to turn away would-be donors who wanted to do something to help after the events of September eleventh, but now Hayes says those long-delayed appointments are being forgotten and missed.