WINNIPEG -- An inquest into the death of a man during a 34-hour emergency room wait will turn its attention to hospital overcrowding and delays rather than focus on assumptions made about the aboriginal double-amputee.

Judge Tim Preston says he expects to hear from about a dozen witnesses as the Brian Sinclair inquest moves into its next phase. Most of the witnesses should discuss how to improve patient flow in emergency rooms and reduce long waits for care, he said.

Preston said Friday he would like to hear one witness talk about how to improve service for aboriginal patients, but he warned this is an inquest -- not an inquiry.

"My mandate is not that broad," Preston said. "The reasons for delay that occur once a person presents at an emergency department, and measures to reduce that delay, are the subject matter of this inquest."

Sinclair's family and aboriginal organizations had hoped the inquest would delve more deeply into systemic issues facing native people seeking health care.

Sinclair's relatives have said they wanted the inquest to examine what they call the racism that led people to assume Sinclair was a homeless person seeking shelter or a drunk "sleeping it off" when, in fact, he was slowly dying in the ER waiting area at Winnipeg's Health Sciences Centre in September 2008.

The 45-year-old hadn't urinated in 24 hours and was referred to the hospital by a community doctor. Sinclair is seen on surveillance footage speaking to a triage aide when he first arrives at the hospital before wheeling himself into the waiting room.

There, he slowly deteriorated, vomiting several times as he waited for care. While Sinclair was brought a bowl, no one asked him if he was OK or if he was there to see a doctor. By the time he was discovered dead, rigor mortis had begun to set in.

While many hospital employees observed Sinclair as he languished in the waiting room, no one believed he was waiting for care.

"It is clear that incorrect assumptions were made about Brian Sinclair by a number of front-line staff," Preston said. "I would ask inquest counsel to present a witness to give practical assistance about best practices for aboriginal health at emergency departments."

The inquest is expected to hear from a handful of senior staff from Winnipeg Regional Health Authority, who are to speak about the flow of patients in the emergency room. Three nurses are expected to address working conditions.

Preston has also requested a witness -- likely to be one from outside Manitoba -- to talk about different emergency room models.

Murray Trachtenberg, lawyer for the Sinclair family, said he'll be analyzing the judge's remarks carefully, but added he's heartened to hear Preston request testimony from an outside expert.

Hopefully the next phase of the inquest can explain how Sinclair was effectively invisible to those working in the emergency room, Trachtenberg said.

"Equally important will be how to make sure nobody else becomes invisible in the future," he said.

The inquest is scheduled to resume sitting Feb. 18 for two weeks and then for another week in June before it wraps up.