CHICAGO—Konrad Poplawski, a 22-year old Navy hospital corpsman, is about to be deployed as a battlefield medic with the 2nd Marine Division, which has served in deadly battlegrounds in Iraq and Afghanistan.

But first, he is making a pit stop at Cook County’s Stroger Hospital, which the Navy says is among few places here in the U.S. that provide experience treating the types of wounds he will inevitably see on the battlefield.

For so long “the first time a corpsman got any trauma experience was when they were deployed, and some would just freeze up,” said Captain Paul Roach, a U.S. Navy surgeon at the Lovell Federal Health Care Center north of Chicago. “We don’t want that to happen anymore,” said Capt. Roach, who heads the program in the Great Lakes region.

The Navy is working to formalize a pilot program that has been tested here for three years, rotating newly enlisted hospital corpsmen—the combat medics for the Navy and Marines—and those needing a refresher while they are back home, for six to eight weeks through Stroger Hospital’s trauma center. The 14-bed unit treats over 6,000 trauma patients yearly, many of them with penetrating, life-threatening wounds akin to those on the battlefield.

Though Chicago is experiencing a sustained drop in murders since a dramatic spike in 2016, it remains a city where a high number of gunshot victims cycle through the trauma center night after night.