One walk through Regions Hospital's COVID-19 intensive care unit reveals the scope of the medical crisis emerging from a fast-spreading pandemic.

Sixteen sliding glass doors are all closed, and behind each lies a patient struggling to breathe. Almost all are on ventilators because their lungs are too weak to work on their own. Clear tubes carry oxygen into their throats and chests, which mechanically rise and fall as their bodies lie still.

On this Thursday morning, 28 COVID-19 patients are in intensive care, with 12 spilling beyond the designated unit to areas designed for heart problems, strokes and surgical recoveries. A total of 97 COVID-19 patients have been admitted to Regions, which is almost full.

Minnesota's experience with the pandemic suggests one-third of patients on ventilators won't survive, even with optimal critical care.

"When we see so many people suffer and so many people who die, that is painful for us," said Dr. Jerome Siy, head of hospital medicine for HealthPartners, which operates the St. Paul hospital.

The daily scene at Regions is playing out in ICUs across Minnesota as the coronavirus that causes COVID-19 sweeps across the state. Open ICU beds were down to single digits in some parts of Minnesota last week, when Gov. Tim Walz ordered a four-week shutdown of bars, restaurants and entertainment and fitness establishments in hopes of slowing the virus' spread to alleviate pressure on hospitals.

From Mercy Hospital in Coon Rapids to Rice Memorial Hospital in Willmar to Regions, ICU beds are filling as quickly as they are opening up. Statewide, 79% of available ICU beds are filled, and 26% filled with COVID-19 patients.

The state's capacity of open ICU beds has declined about one percentage point per day the past two weeks — raising the probability that some of the 408 ICU surge beds might need to be activated in unused hospital and nursing home wings.

"There's no beds anywhere," said Dr. Matthew Klee, whose ICU at Mercy is full and under pressure to take patients throughout Minnesota and western Wisconsin. "It's become like a game of chess over the entire state."

At one point this month, 30 people were in the Regions ER waiting for inpatient admission due to lack of beds.

Deferrals of noncritical surgeries and efforts to send stable COVID-19 patients home with monitoring have helped but "it's still not enough," said Dr. Kurt Isenberger, a HealthPartners ER physician and critical care researcher. "We are still seeing bed delays for patients in our emergency department."

Toll on workers

More worrisome are the growing infections among health care workers who then can't care for patients.

HealthPartners on Friday reported 308 workers absent due to COVID-19 infections and 414 who were quarantined due to viral exposures. Collectively, the Allina Health, CentraCare and Mayo Clinic systems reported more than 3,000 such absences last week.

Bethany Webb said it has been exhausting picking up shifts for ill colleagues. On a recent Thursday morning, the intensive care nurse is working in Regions' COVID ICU. Paired with her is Susan Ehman, who responded to the pandemic crisis by returning to bedside nursing after five years in an administrative role.

"A lot of our patients are so sick, they need one-to-one nursing," Webb said.

Stands with IV bags and monitoring panels would normally be at the bedside of Webb's patients, but instead, they are tethered by long clear tubing from the patients outside to her station. That way, the nurse can adjust medication or oxygen-flow levels without entering the room, which would require donning gloves, gowns and a face shield to reduce the risk of getting infected by a patient.

An alarm sounds on one of the panels. One of Webb's patients is moving around. Caregivers face constant tension between using the minimal amount of sedation necessary and keeping patients still so they don't disrupt the breathing tubes in their throats and injure themselves.

"Try to stay real still, honey," Webb told her patient.

This fall's surge is different from the one hospitals endured in the spring. At its worst, the first wave produced a third of the patients that hospitals are now admitting, but the uncertainty and mystery surrounding COVID-19 at that time raised anxiety.

Hospitals didn't have stable supplies of masks and personal protective equipment (PPE) and enacted conservation methods — such as bagging then reusing disposal N95 masks — that doctors and nurses feared might not work against a new and highly infectious coronavirus. And nobody knew what would improve recovery odds for severe COVID-19 cases.

Siy said PPE supplies are sufficient now, and while caregivers are still working with caution there is less fear of infection on the job.

The anxiety now comes from nine months of a pandemic that doctors and nurses can't just leave at work, he said.

"We bring that home with us because we are living it at home, too," Siy said. "Kids aren't at school. Things are canceled."

The risk to health care workers now is increasingly outside the hospitals and COVID-19 units, where caregivers know who has the virus and how to take precautions.

In the 30 days ending April 20, the Minnesota Department of Health reported 812 viral exposures involving hospital workers, and 95% involved contact with infected patients or co-workers without sufficient protective gear. In the 30 days ending Oct. 20, 53% of the 622 exposures were due instead to contact with infected people in their homes or at social engagements.

Still a mystery

The COVID-19 ICU at Regions is oddly quiet given the crowding of patients. No visitors are allowed except in extreme circumstances. The doors are closed to maintain negative air pressure, so viral particles coughed by patients don't blow into the hallways and infect doctors and nurses.

Around the corner from Webb's station are two nurses completing observational training to take on ICU shifts.

Jenny Borut had wanted to travel to New York in the spring to help address the COVID-induced hospital bed shortage there, but it felt unsafe to risk infection with her husband and children at home. Knowledge of the virus and how it spread made it a safer decision to return to critical care nursing locally this fall. "My heart and my passion has always been the ICU," she said.

Behind each glass door of the COVID-19 ICU at Regions is a puzzle, because much is still unknown about optimal critical care for those infected.

Blood clots are increasingly recognized as a source of fatal or disabling complications, but overtreatment could lead to bleeding. The infection has been startling for its impact beyond the lungs and oxygenation of blood, and its effect in some cases on the brain, kidneys and other organs.

The glass doors on the unit are coated with marker drawings noting patients' needs.

"* likes classical music," one scribbling reads. "Jean Sibelius, Dmitri Shostakovich, Beethoven."

On the unit's far side is a door with a long list of dates and times — an incremental tracking of when the COVID-19 patient inside was rotated from his back to his stomach, and then back again.

The "proning" of COVID-19 patients is an example of the art matched with the science of treating the pandemic.

There is growing evidence that the practice helps COVID-19 patients in respiratory distress by distributing oxygen evenly to their damaged lungs, improving the oxygenation of blood and shortening or even preventing the amount of time that ventilation is needed.

What's lacking is agreement on how often to rotate patients, or which ones to select for the physically demanding and resource-intensive procedure. It takes six to nine caregivers — in short supply — to safely turn over one patient.

Regions has taken the practice to the extreme, encouraging COVID-19 patients even in general beds to turn over to keep their lungs functioning.

There is no proof this helps patients who aren't in critical care, said Chris Boese, Regions' vice president for patient care. "They just feel better."

A physician group continually evaluates studies and evidence about COVID-19 — with some treatments such as the antiviral remdesivir and donor convalescent plasma showing early promise and then some underwhelming follow-up study results. The standard practice is to throw all of the treatments at critically ill patients, making it hard to know which ones turn them around, Siy said.

"It's not just how one of them works," he said, "it's how they all work together."

This is the first in a series on Minnesota hospitals' response to the surging COVID-19 pandemic.