CEDAR RAPIDS, Iowa (AP) — A nurse anesthetist has pleaded guilty to tampering with opioid painkillers in northern Iowa. Records for the U.S. District Court in Cedar Rapids say Christopher West also pleaded guilty to obtaining a controlled substance by deception. The Waterloo-Cedar Falls Courier reports that West had been accused of ordering extra painkillers so he could use the leftovers. Prosecutors also say West reported several times that painkiller vials broke when he dropped his anesthesia kit at the Floyd County Medical Center in Charles City.

Prosecutors say he actually stole the vials and used the painkillers himself. Hospital officials who’d grown suspicious of West last year also checked a supply of painkiller vials and ampules and found they’d been opened, the painkiller replaced with saline and then glued back together.