Dr. Rex Dunn

Dr. Rex Dunn, the chief of staff at the Cape Breton District Health Authority, has gone over notes on mortality rates after every major surgery at the Cape Breton Regional Hospital in Sydney. (Yvonne Leblanc-Smith/CBC)

A review of high mortality rates after major surgery at the Cape Breton Regional Hospital in Sydney did not find a common cause, but health officials say most patients were elderly and had serious underlying medical issues.

A report last year found 16 out of every 1,000 surgeries at the Cape Breton Regional Hospital resulted in death — that number is twice the national average.

Dr. Rex Dunn, the vice-president of medicine and chief of staff for the Cape Breton District Health Authority, said each patient's file was studied. Most of the surgeries were emergency surgeries that happened after hours on elderly patients with serious underlying medical issues.

"What we found was a potpourri of diagnosis, really terrible diagnoses in some of these people," he told CBC News.

"People that were frail and elderly, people with cancer. So really, it's hard to find that silver bullet to say, 'Look, here's the problem. Let's fix it.'"

Dunn said most patients were between the ages of 75 and 90. They turned up at the emergency department with health issues such as broken hips, perforated bowel and bowel strangulations, then suffered strokes, ruptured aneurysms and heart attacks.

"That can be the final result of a series of stresses on somebody that is frail and elderly," said Dunn.

Dunn said he saw no evidence that post-operative care played a role in their deaths, nor was infection a factor.

While the review did not produce a silver bullet, Dunn said it gave staff the resolve to step up screening for early heart attacks, expand pre-anesthetic assessments and have hospital teams review surgical cases more often.

Dunn said he is feeling better about the situation after reviewing the files, but won't be entirely satisfied until he sees an improvement in the mortality numbers.