Samer Attar, a surgeon with Northwestern Medicine in Chicago, is a volunteer with the Syrian American Medical Society and the Aleppo City Medical Council.

“Please don’t cut off my leg,” a Syrian man pleaded. He had been shopping when a missile hit a crowded market. The blast seared off his hair and charred his face. He could not see that his leg was hanging by a thread of flesh and could not be saved. His screams were amplified by the echoes of the dozens just as horrifically injured around him.

I am an American surgeon who recently spent two weeks working in an underground hospital in eastern Aleppo, Syria. I have been there a few times, and each time I go, I descend into lower depths of hell. It’s shocking how the very same inhuman conditions have been allowed to continue for years.