TORONTO -- As the third wave overtakes the province, with no sign of slowing down, Ontario鈥檚 hospitals are turning into war zones 鈥 and those working in the ICUs are warning that we鈥檙e not just running out of beds, but also of the people capable of treating the patients in them.

Over the weekend, hospitals in the Toronto area have been experiencing an unrelenting influx of patients sick with COVID-19.

鈥淭he pace of ICU admissions last night at Brampton Civic [Hospital] alone, there were nine ICU admissions in one 12-hour period,鈥 Dr. Andrew Healey, an emergency critical care doctor with William Osler Health System, told 麻豆影视.

He said 36 patients were admitted to the ICU at the hospital he works at within a 24-hour period the day before, 鈥渁nd that鈥檚 the highest number in the pandemic by a lot.鈥

鈥淭his is really the most challenging wave, and these are the most challenging days we've seen from this pandemic,鈥 Kevin Smith, president and CEO of the Toronto-based University Health Network (UHN), told 麻豆影视. 鈥淎nd unfortunately, the next two weeks will be very trying.鈥

The health system is attempting to make room for the flood of patients as cases rise. Elective non-urgent surgeries have been postponed again. Hospitals in the Greater Toronto Area have been ordered to close their pediatric units, and those patients are being sent to Toronto's SickKids, which has also opened up eight adult ICU beds.

鈥淎s of this morning, we have seven of these eight beds filled with adult patients who are in our ICU,鈥 Dr. Ronald Cohn, President and CEO of SickKids, told 麻豆影视.

Figures from Health Canada show that the percentage of patients in intensive care who were between the ages of 18 and 39 doubled from January to March, increasing from 7.4 per cent to 15 per cent of the total number of ICU patients.

These patients, being younger and healthier, likely have a better chance of surviving longer. While that鈥檚 good news, it also potentially means a larger strain on the health-care system while patients battle severe illness for longer.

And many patients who doctors are seeing are essential workers, whose risk level has not been changed by lockdowns instated by the province.

鈥淚 worry because in our region, a large percentage of these cases are coming from essential central workers,鈥 Healey said. 鈥淭hat makes me really worried [because] a lot of those people are still going to work.鈥

An all-time high of more than 600 COVID-19 patients are currently in the ICU in Ontario 鈥 and that number is only expected to grow in the coming days.

鈥淲e're expecting [鈥 about 1,000 patients in Ontario ICUs across the province by the end of this month, which is about half of our ICU capacity,鈥 Dr. Chris Simpson, executive vice-president of Ontario Health, told 麻豆影视. 鈥淎nd remember, ICUs [have] that kind of capacity because we need them for other things too, so it's really a dire situation.鈥

Front-line teams, usually reserved and optimistic, now have a desperate tone, signalling that despite the field hospitals, Ontario may run out of room.

鈥淲e're sort of quickly approaching a cliff set and we're seeing increasing numbers being admitted to ICUs,鈥 Dr. Bram Rochwerg, associate professor at McMaster University and critical care lead at the Juravinski Hospital in Hamilton, told 麻豆影视.

鈥淸We鈥檙e] stretched in terms of capacity and places to put patients, as well as staff. I think the most alarming point is that despite the increasing numbers and the Band-Aid solutions that we're coming up with trying to care for more critically-ill patients is that we have yet to see the plateau, even in provincial numbers.鈥

He pointed out that there is a delay between patients testing positive for COVID-19 and their illness worsening to the point of needing to be taken to an ICU.

Which means that any number of the 4,500 patients who tested positive today in Ontario may be in the ICU two weeks down the road.

Smith said the most concerning statistic isn鈥檛 necessarily the amount of beds that they have, it鈥檚 how many doctors and nurses they have who can help the patients in the beds.

鈥淚t's a bit like having your car 鈥 if you have a car, but nobody can drive, you don't get very far,鈥 he said. 鈥淥bviously you want someone who knows how to drive behind that wheel, and critical care is a complicated discipline of medicine, particularly when you're dealing in a pandemic environment and the demands are as high as these. So we want experienced people who are used to dealing with life-threatening illness.

鈥淭he number of people who are are trained in critical care is a limited resource.鈥

And hospitals can鈥檛 shift every single resource to COVID-19 patients, because unplanned emergencies such as heart attacks, strokes, car accidents and other life-threatening injuries are still occurring, and doctors need to be available to treat those patients.

Dr. Kashif Pirzada, an emergency physician, told 麻豆影视 that health-care workers are trying to fill every role, and help wherever they can.

鈥淩ight now, physicians and nurses are being drafted into working in extend ICUs, reusing every space possible 鈥 the operating room, the recovery rooms, the cardiac units 鈥 and we're also running out of special drugs that are really effective for COVID patients.鈥

Healey added that recently they鈥檝e faced shortage in things other than staff and . He explained that the night before, they had briefly run out of a specialized type of oxygen masks, and that they had run out or come close to running out of 鈥渉igh flow nasal canula[s]鈥 on other occasions as well.

In order to free up resources, patients are also being shuffled around to other hospitals at a much higher rate than before the pandemic. Patients are being sent to hospitals outside of the GTA in some cases because of the heavy load on some of the hospitals inside the hard-hit city. But in order to send a patient potentially thousands of kilometres away from where their loved ones live, hospitals need the consent of their families, one more step complicating the process, Rochwerg explained.

鈥淲e're seeing patients being sent from the Toronto area to London, beyond London up into Northern Ontario, and trying to use up all the resources and all the beds that the province has,鈥 he said.

It鈥檚 scary, doctors say. They鈥檙e stretched thin, overworked and tired, dealing with trauma and death on a regular basis. And they say it鈥檒l get worse before it gets better.

鈥淭here's a limited capacity to take care of everybody,鈥 Simpson said. 鈥淎nd without that wave coming down, it will be extremely problematic.鈥

But Healey said when he comes into work every day, he does so 鈥渨ith focus,鈥 and with an awareness of how critical this stage of the pandemic is.

Smith praised the hard work of those in the health-care system, saying he鈥檚 never seen this type of collaboration.

鈥淚t's as though we have one hospital in the province of Ontario with the moves we're making, the way people are collaborating, [鈥 and so hats off to the frontline providers,鈥 he said.

鈥淏ut they are tired, we've been out [in] this for a year, over a year. And now, this is our biggest surge yet, [it鈥檚] daunting.鈥