The Rocky Mountain Regional VA Medical Center in Aurora still cannot identify the residue that has forced the hospital to postpone or move hundreds of surgeries since April.

Initial testing of the substance came back as inconclusive, said Janelle Beswick, a regional spokesperson for the U.S. Department of Veterans Affairs. Another lab found that a sample from a sterilizer filter was plastic and not biological material.

“We are working to collect a larger sample of the residue to retest and pinpoint the exact source,” she said.

As of June 13, 436 surgical cases and 103 dental appointments have been impacted.

The Aurora VA has been working with the Cheyenne VA and a private vendor in Colorado Springs to sterilize the hospital’s reusable equipment. The Aurora VA has also placed mobile sterilizing equipment in the operating room area, allowing the hospital to resume some surgeries, Beswick said.

Dental sterilization has also resumed after tests showed that department’s equipment contained no residue.

The Denver Post first reported May 10 that the Aurora VA was halting surgeries in light of the mysterious residue. Internal VA emails reviewed by The Post show the issue cropped up as early as April, after which the hospital began rescheduling all surgeries that involved reusable medical equipment.

VA officials previously have described the residue as black flecks found on the hospital’s reusable surgical instruments.

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Originally Published: June 17, 2024 at 12:18 p.m.