The first group meeting was held for patients whose surgeons unknowingly washed instruments in hydraulic fluid instead of detergent.

A freelance medical writer organized the meeting of about 50 people. He was one of 3,800 patients who underwent surgery with instruments washed in the fluid in late 2004, at two hospitals onwed by Duke University Health systems.

Workers at Durham Regional Hospital and Duke Health Raleigh Hospital complained the instruments were slippery before discovering hydraulic fluid had been accidentally used instead of soap in washing machines that clean surgical tools.

The fluid came from a hospital parking garage where workers drained it into empty soap containers while working on an elevator. They later packaged the containers into pallets and shipped them back to the distributor, who reshipped them to the hospital when soap was ordered.

Shirley McCaden, who underwent back surgery at the Durham Hospital, says she suffered rashes and pain and her hair has fallen out since the operation.

A report by the federal Centers for Medicare and Medicaid Services says the hospital oversight has put patients in "immediate jeopardy," while state investigators do not consider the problem to be serious