The Duke University health system said a third hospital in North Carolina is involved in an unusual incident in which surgical instruments were washed in hydraulic fluid left behind by an elevator repair crew. Officials at Wake Forest Baptist Medical Center said staff discovered the mistake before any patients were put at risk. More details in the error are emerging. The Washington Post reports that supplier Cardinal Health was involved in shipping the mislabeled vats of hydraulic fluid from a warehouse to a "number" of hospitals in North Carolina. Story