STORY: On the heaviest days of fighting in east Ukraine, teams of army doctors near the front line can carry out five amputations at a time.

This military hospital in the Donetsk region treats soldiers wounded in some of the fiercest battles in nearly 10 months of war with Russian forces.

Okeksii, an army doctor who didn't give his last name, says the main thing they can do is stabilize the patient and try to save damaged limbs to prevent blood loss.

"There are days when there are many heavily wounded: four or five amputations at once. On other days there is no one for two, three or four hours. No day is like another. Sure, there are difficult days, especially when ours are attacking. Then the work can go on for five, six, seven hours straight."

Medical staff try to lift soldiers' morale by putting up children's drawings, with messages that hail them as warriors and pray for victory.

Oleksii Nazaryshyn, a brigade military service chief, says the main goal is, quote, to make sure "the boys don't die, and reach the next evacuation point."

Some staff struggle to hold back tears as wounded young men are carried in on bloody stretchers.

Olena, an intern, says they often beg to be treated and sent back to the battlefield instead of home.

“To be honest, it is mentally very hard when very young boys are being brought in. We've transported boys without legs who were born in 2002 and 2000. It is mentally very hard. When you’re alone you can cry, but when you go through the doors you have to smile because they are looking at you and are saying ‘I am already doing better’.”

Kyiv says the brutal fighting on the eastern front is inflicting huge losses on Russian forces as well as taking its toll on Ukrainian soldiers.