The Winnipeg Regional Health authority says it is analyzing why 72 people died after so-called critical incidents in city hospitals and nursing homes last year.

The WRHA reviewed more than 2,600 cases where patients died in 2008 to determine if medical or procedural errors contributed to those deaths.

Among cases reviewed was that of Brian Sinclair, a double amputee with a speech problem who was found dead in his wheelchair on Sept. 21, 2008, after he spent 34 hours in the waiting room of a hospital emergency department.

His death could have been prevented if a blood infection, brought on by complications of a bladder infection and blocked catheter, had been treated sooner, the province's chief medical examiner said.

Dr. Rob Robson, the WRHA's chief of patient care, said the review shows about one-fourth of the 72 critical incident deaths occurred following "medication issues" and another fourth after "procedural issues" such as surgery. The cases are now being reviewed more thoroughly.

"We haven't done as much of a thorough breakdown as we'd like to, but that's coming," he said.

"It doesn't look as if there's anything different in the categories that lead to unintentional patient harm," he said.

Some of the deaths involved actual medical errors, he said, although he did not say how many.

Robson said 55 of the deaths reviewed happened in hospitals, and the remaining 17 in personal care homes and long-term care facilities.

Nearly all the cases involved patients with complex medical conditions.

Robson said the WRHA still has work to do to convince medical staff that they should be reporting all such cases but had no evidence the incidents were concealed.