War 'Games': How Ukraine's Hospitalized Kids Fight for Survival — and Solace — in Russian Invasion

As Russia's invasion of Ukraine intensifies, doctors in at least one pediatric hospital have taken to playing a "game" with their patients. Whenever the shrieking of bomb sirens begins, children must rush as quickly as they can to the "dungeon," a.k.a. the hospital's basement, for shelter.

It's quite literally a competition for survival, and Dr. Roman Kizyma, the lead pediatric oncologist at the Western Ukrainian Specialized Children's Medical Center in Lviv, told NBC News on Monday that he knows these wartime diversions are still "traumatizing" for the young people under his care.

About 540 miles east in the capital city of Kyiv, doctors "run five or six times a day in the basement and back" with patients, according to surgeon Vitaly Demidov.

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Demidov told TIME that he and his colleagues at Okhmatdyt Children's Hospital race alongside gurneys, operating manual ventilators for children who need oxygen support. In Kizyma's hospital in Lviv, near the Polish border, children who need oxygen don't even have that option — they must be left behind in their beds while others shelter downstairs.

For any doctor, every day is a series of life-or-death choices. But as Russian forces bear down on Ukraine, the country's pediatric doctors are feeling overwhelmed by the surging tide of casualties.

Though a precise count of the dead and wounded is nearly impossible at this time, official figures place the number of those killed since Thursday's invasion in the hundreds — and the number of children who have lost their lives grows by the day.

Volodymyr Vovkun, another Okhmatdyt surgeon, the The Wall Street Journal: "It's just so vile."

Okhmatdyt, which is Ukraine's largest pediatric facility, already evacuated patients with non-life-threatening conditions, according to TIME. But the number of kids who cannot leave the hospital is increasing — even as everyday necessities like insulin and baby formula become more scarce.

Treatment disruptions also present a looming threat. If they persist, Okhmatdyt's Dr. Lesia Lysytsia told NBC News, "our patients, they will die."

Many children cannot reach the hospital and "are just dying at home," Okhmatdyt Director Volodymyr Zhovnyakh told the Journal.

Lysytsia said that, eventually, "We will calculate how many people or soldiers have died in attacks, but we will never calculate how many patients weren't diagnosed of a disease in time, how many patients died because they didn't receive treatment. It's an epic amount of people."

And those who try to leave are also in danger, according to Julia Nogovitsyna, the program director at Ukraine's largest child cancer charity, Tabletochki.

"Patients and their parents ask me if it's safe, and I say, 'I don't know,' " Nogovitsyna told NBC News. "I don't even know if it's safe to go outside. It's possible they go out near the hospital and they'll be attacked." (She noted that attacks have been particularly frightening at the Polish border, where an escalating rush of refugees has led to an atmosphere of fear, anger and tension.)

"What is happening now in Ukraine is a humanitarian catastrophe caused by the war," Okhmatdyt director Zhovnyakh told the Journal. "The world is watching us, praying for us and not doing much else. Ukraine, unfortunately, is on its own."

Back inside the hospital, family members keep vigil by the beds of their loved ones.

"I live in fear, but not for myself. Every morning I wake up, cross myself and pray that nothing hits the ICU room," Krystyna Krayevska told the Journal of staying with her 6-year-old niece Darynka, who is on life support after complications from a brain tumor surgery. "She is fighting for her life, up there, and we down here are fighting for our own lives, thanks to the Russian soldiers."

And as Ukraine's men of fighting age (18–60) have reportedly been required to stay in the country in case they are needed for the battles to come, those with children in their lives face a harrowing daily question of loyalty.

"If not for the baby, I would be on the front lines too, fighting until my last breath," said Valentyn Vetrov, whose 1-year-old son has undergone multiple surgeries to correct a birth defect.

"But for now," he said, "my duty is here."

The Russian attack on Ukraine is an evolving story, with information changing quickly. Follow PEOPLE's complete coverage of the war here, including stories from citizens on the ground and ways to help.