TORONTO — Mass-casualty disasters like Monday's deadly van attack that sent 10 of the victims to one Toronto hospital are a relatively rare occurrence in Canada. So how do hospitals and their staff prepare for that moment when a Code Orange alerts them to expect a sudden influx of often critically injured patients?
For Sunnybrook Health Sciences Centre, the regional trauma centre where those patients were transferred, the answer is ongoing education and practice drills for staff who work in all areas of the sprawling complex in the north end of the city.
Dr. Dan Cass, Sunnybrook's chief medical executive, said the hospital has a Code Orange plan that helps administrators determine whether staff already on shift can handle the number of expected patients or if extra doctors, nurses and other practitioners will need to be called in.
"We were fortunate with the time of when this happened (early afternoon) because we had a lot of people in-house, so we were able to manage at least the first phase without additional resources," Cass said. "We called people in later."
Beyond the paper plan, the hospital also carries out monthly table-top sessions, in which different groups of staff meet to discuss potential mass-casualty scenarios.
"People sit around the table and they're thrown new events that happen and have to respond to it: 'How would we empty out the ICU right now? How would we get this patient to the OR?'" he said.
"So they practice the components of a Code Orange response without actually walking through the motions."
But about once a year, the hospital also organizes a multiple-victim simulation, often using students as would-be patients to give groups of staff hands-on practice.
Debriefings are also part of the preparedness process, so lessons learned from the experience can help "fine-tune the response for next time."
Of the 10 patients brought to Sunnybrook on Monday, two were pronounced dead soon after arrival. On Tuesday, five remained in critical condition, two were serious and one was listed as fair. In all, 10 people died and 16 were injured.
Alek Minassian, 25, of Richmond Hill, Ont., was charged Tuesday with 10 counts of first-degree murder and 13 counts of attempted murder, following a bloody rampage in which the driver of a rented van mowed down pedestrians on a stretch of Yonge Street in north Toronto.
Cass described Monday's inrush of patients following the van attack as "organized chaos" as emergency room staff began providing care to the injured, while patients already in the ER and the ICU had to be moved elsewhere in the hospital to free up space for the new arrivals.
"I stood outside the trauma room as the first patients arrived and I was thinking how calm things were because people were focused on what they do every day," he said. "They were just doing more of what they're used to."
..I think part of the deal is that emergency physicians and emergency nurses are innately wired to transform chaos into calm.
Dr. Alan Drummond, chair of public affairs for the Canadian Association of Emergency Physicians, said many people might be surprised to hear that the response to multiple injured patients coming through the ER doors was orderly and calm because the public tends to believe that staff would feel overwhelmed by such a sudden onslaught.
"They're not actually," said Drummond, an ER doctor at the Perth and Smith Falls District Hospital. "And I think part of the deal is that emergency physicians and emergency nurses are innately wired to transform chaos into calm.
"It's something they do on a regular basis," he said, noting that ER staff in Canadian hospitals come into work daily to be met by crowded waiting rooms and every stretcher occupied by patients with a broad range of symptoms and conditions that have to be triaged, diagnosed and treated.
"And because we're so innately wired, I think that that comes to the fore, when we do rarely face those mass-casualty problems. The physicians and nurses are highly professional, they're well-trained, so they know what they must do."
More from HuffPost Canada:
Like other acute-care institutions, the Perth and Smiths Falls hospital southwest of Ottawa also has a Code Orange preparedness plan and annually has at least paper-based practice sessions, which are a requirement for continued hospital accreditation.
"So every hospital I know of yearly at least has a paper exercise in terms of mass-casualty incidents, and that usually involves making sure there's an effective call list so everybody can be contacted, from extra ancillary help, be it radiology, laboratory investigation, extra nurses and extra physicians," Drummond said from Perth, Ont.
"(It's) making sure the consultants are available, operating rooms are ready and that the whole organism of the hospital is prioritized to helping the transition from the emergency department to the operating room in a fairly seamless manner."
And it struck me that this is what we actually do — this is our job.
In his 35 years at the hospital, Drummond said he's been involved in only one incident in which multiple victims were rushed to the ER, following a horrific crash on Highway 7 south of Ottawa in the late 1990s.
"That was the only time our hospital has had to face a mass-casualty incident," he said. "It was around midnight or one o'clock in the morning and I got called in.
"I remember walking in to what I thought would be total chaos, and yet it was calm and quiet and everybody worked professionally to make sure that the most injured patients got dealt with.
"And it struck me that this is what we actually do — this is our job."
CLARIFICATION - April 27, 2018: Previous reports from Toronto police stated that 14 people were injured in the Toronto van rampage. Officials have since updated that number to 16.
Also On HuffPost: