He's seen them come back for an instant and then fade just as quickly.
Chavez looks at Kristina and then at the emergency staff.
He turns back to me and shakes his head.
"She's gone," he says.
Her eyes are still open, looking at nothing. Kristina's clothes are removed and her body is wrapped in white plastic. They make the last fold and she's gone, and the stabbing victim next to her isn't far behind.
Chavez leaves the emergency room with heavy steps. Over coffee a few minutes later, he's still wondering why Kristina turned so quickly and what did her in, besides the obvious ravages of heroin.
"I just hate that helpless feeling," he says. "You're standing there watching, and there's nothing you can do."
But the calls keep coming, so there's no time to dwell on it. Besides, Chavez has probably saved more skid row people than he's lost.
"You can't let it get to you," he says. "If it gets to you, your career is over."
Chavez should have moved on from Station 9 by now, worn down by the endless wail of 911 calls and the psychological toll. Others deal with it for a few years and then, jumpy and jaded, bounce back to firefighting. Or they transfer to quieter stations and the relative comfort of ordinary disaster.
Not Dave Chavez. He has kept this same job — a young man's job — for 10 of his 23 years with the Los Angeles Fire Department. He keeps at it because he's good and because he likes bringing along the younger talent.
And maybe, too, because there is no better way to honor his father, a retired firefighter, than to work in the busiest station and handle the job like a pro. At the end of his shift, Chavez often stops at the Cerritos home where he grew up. He and his dad sit there with their coffee and their stories, and the day begins.
Back on San Julian Street, I break the news.
"Who's dead?" Sporty asks, hyped up and jittery.
Kristina, it turns out, wasn't her real name. But nobody knows what it was. No one knows her last name, either. They think she was from El Monte, but who could say?
All they know is that she slept here among them when she wasn't in jail. They say she had a baby recently. No one knows where the baby is. No one knows anything out here, except where to get heroin. She wet herself regularly, too far gone to bother getting up, no strength left for anything but the needle.
Those are her things, someone says, pointing to a black garbage bag that contains everything the dead woman owned. No one wants to open it. It wouldn't be respectful.
The bag is still there at midnight, under three bouquets of flowers and a sign:
"We Miss You Homegirl."
Sporty is still there, 34 and a former gang member. So are most of the others who live in this encampment. A woman of 20 is sitting on a blanket, calmly lighting a crack pipe.
"We treated her like a leper," Sporty says of his fellow addict, suggesting a social order among junkies.
Even as drugged out as he is, it's eating Sporty up, the way he and others gave her such grief for not taking better care of herself.
"I feel sorry I didn't treat her a little better," he says. "I wish I had treated her with a little more humanity."
I wonder if what's really bothering Sporty is that he's dying too, killing himself the way she did. Right here on San Julian, a half block from the firehouse where Dave Chavez is waiting for the next call.
Follow Steve Lopez's experience on skid row and ride with paramedics at latimes.com/skidrow. Reach the columnist at email@example.com.