Kristen Diane Parker, the Colorado scrub tech who stole fentanyl syringes by swapping them for used, saline-filled ones, potentially infecting surgical patients with hepatitis C, is expected to enter a guilty plea with federal prosecutors.

Ms. Parker, 26, who faces 19 counts each of tampering with a consumer product and illegally obtaining a controlled substance, asked a Denver court on Thursday to strike her trial, which had been scheduled to begin Sept. 28, and to schedule a hearing today, at which she would presumably withdraw her plea of not guilty, according to local sources. The terms of the plea agreement are not yet known.

Ms. Parker's alleged crimes took place at the Rose Medical Canter in Denver and the Audubon Surgical Center in Colorado Springs. State officials have linked 35 cases of hepatitis C to patients' procedures at the 2 centers during Ms. Parker's time there. Investigations are also being conducted at facilities in New York and Texas that had employed her.

Earlier in the week, federal prosecutors had subpoenaed the Audubon Surgical Center to disclose the identity of a patient who may have been infected by Ms. Parker's actions in order to build their case, but according to a news report, the center opposed the demand on patient privacy grounds.

While it supplied prosecutors with HIPAA-compliant, identity-redacted medical records, it refused to name the patient, honoring the patient's wishes. Audubon Administrator Brent Ashby declined to comment on the issue.

David Bernard