Washington, D.C.'s Engine Company 10 is one of the busiest fire departments in the country. It's widely known as the "house of pain" because of the grueling pace the firefighters keep.
On any given day, they'll respond to about 25 calls in a 24-hour period.
The firefighters love putting out fires. But what makes Engine Company 10 so very busy is this: The vast majority of the 7,000-plus calls the firefighters answer each year are not fires at all. They are, in fact, medical calls.
"Nightline" followed the department over many shifts and several days. Many medical calls came in. A woman, combative and running into the street, was thought to be on the drug PCP. A 50-year-old man hemorrhaging blood because of -- he says -- a mistake in his routine kidney dialysis treatment. An 82-year-old woman bleeding from her rectal area. An 83-year-old with respiratory distress.
Leo Ruiz is a paramedic firefighter with Engine Company 10. He has all the training and skill of an Army battlefield medic. Like many of his fellow firefighters, he loves serving his community.
But he signed up to fight fires. And as we followed Engine 10, we saw it happen again and again. When the men at Engine 10 arrive on the scene of a call, it's not a fire hose they pull out; it's a medical bag.
The engine company serves a neighborhood called Trinidad, where most people are poor and don't have good access to doctors. They get sick and they call 911. Emergency operators then call in Engine 10.
The firefighters call the community they serve "the vortex of sickness."
"It's an area where we run a lot of sick people," said firefighter JR Muyleart. "A whole lot. If they drank more of this," he laughed, holding up an orange juice container, "they'd cut down on health care costs."
"Vortex of sickness" is a name that reflects both the real medical needs of the area and a certain level of frustration among the firefighters.
Ruiz described one call as it was happening.
"We're going for a 20-year old-female with a headache," said Ruiz. "Most of the time, it is [minor]."
That's not to say these firefighters don't get their fair share of real medical emergencies. On one call they found a 24-year-old man in full diabetic coma, unconscious on a couch.
"What's going on today, sir?" asked Ruiz, shaking the man. "What's your name?"
The patient did not respond, but he started to stir.
"It looks to me like his sugar's low and we can fix that real quick," said Ruiz. "Do you guys have anything in the house that he can eat?" Ruiz asked other people in the home.
Muyleart read out sugar levels. Ruiz and firefighter Michael Brook prepped an IV bag.
"We're gonna go ahead and help him out, OK?" said Ruiz. "What we'll do is we'll start an IV."
It's not the first time this particular patient has called 911.
"This ever happen to you before, that your sugar dropped low?" Ruiz asked the patient, who told him it happens "all the time." "When's the last time that happened?" Ruiz asked. The patient explained that it happened so frequently he couldn't think of the last time.
"Do you want to go to the hospital with us today?"
The patient said no.
But just minutes after returning from reviving that man from a diabetic coma, they had to go back. He thought they had stolen some of his money.
"He thought he lost money. So he called the ambulance," said Ruiz.