A certified nurse anesthetist has pleaded guilty to giving himself pain medication intended for patients at two Virginia hospitals. Alvin Earl Parkes admitted Thursday in U.S. District Court in Roanoke to two counts of obtaining controlled substances through fraud or deception. U.S. Attorney Julia C. Dudley said the 62-year-old Draper man diverted fentanyl prescribed to pregnant women and patients undergoing surgeries and such procedures as colonoscopies.