A former Minnesota nurse has been sentenced to two years in prison for stealing painkiller medication at the hospital where he worked. A federal judge on Wednesday also ordered 43-year-old Blake Daniel Zenner of Kimball to pay $340,000 in restitution. Zenner pleaded guilty last September to one count of obtaining a controlled substance by fraud. In his plea agreement, he admitted that he siphoned Dilaudid from IV bags at a St. Cloud hospital for around 4 months. Prosecutors say he sometimes injected the bags with saline solution to replace the missing Dilaudid. Around 25 hospital patients were reportedly infected with bacteria as a result.