Although I'm an EMT, I don't work areas like that but I have heard many horror stories of EMS workers who do. Wearing body armor is common, as is being threatened or shot at when they respond to 'certain areas'.
Gang-bangers don't want you helping the person they just shot, they want him to die.
There is definitely an underbelly of society that thoughtful people need to avoid at all costs. It's not racism, it's self-preservation.
That was what was truly strange, since at any moment, they themselves could have been in that same position.
When I lived in New York, one of my friends in the office was a black woman who lived in Harlem and whose sister was a nurse at Harlem General. Her sister had to deal with all the garbage that was brought in after gang shoot-outs, etc. One time, she had a lightly injured gang banger on a stretcher cussing her out because he wanted a glass of water while she was dealing with somebody who had a gut wound. When she went by him, she leaned down and hissed in his ear, "I hope you die." He didn't, for better or for worse, but it made her feel soooo good to say this!