The 28th Combat Support Hospital in Baghdad's Green Zone is the busiest military trauma center in the world. Casualties can arrive with as little as a one-minute warning.
"Probably about 95 percent of our casualties come in by air," said Maj. William White, the head nurse. "Since the surge started, we are seeing more coming in by ground."
Since White arrived in October, the hospital has treated close to 9,000 trauma patients. Iraqis, both friend and foe, are treated here, but mostly American soldiers and Marines have passed through its doors.
Just after noon on the day "Nightline" visited the facility, a convoy pulled up to the entrance. An Iraqi mother had waved the convoy down as it passed by. The day before, her daughter had been bitten by a black scorpion and now the 8-year-old girl was unconscious and struggling for breath.
While doctors and nurses worked to insert a tube to help her breathe and an IV line to deliver fluids and medication, White and his staff were alerted that a helicopter was now on its way. All that was known about the wounded U.S. soldier on board was that a roadside bomb had blown up his legs.
Second Lt. Mark Little is just 23 years old, college educated, the youngest of eight children and the only one of his siblings to join the military. He was helping to deliver supplies when his Humvee was struck. This was the fourth bomb he had been hit by since arriving in Iraq in May. Until today, he had escaped serious injury. When he arrived at the hospital, the lower part of his right leg was gone and the lower part of his left leg was barely attached.
Little was semiconscious, but White spoke to him to help put his mind at ease.
"Mother and father — I bet they are pretty proud of what you are doing," he told the soldier.
He also tried to keep Little informed of what was happening around him.
"The name of the game here is we are going to get a CAT scan. And then see if we can get an O.R. opened up right away and fix you the rest of the way up. OK?"
Little weakly asked about his legs.
"We are going to do what we can to fix your legs up as much as we can," White told him. But he didn't sugarcoat the lieutenant's situation.
"You know the deal, right?" he asked.
Little managed a joke about not having to run any more two-mile training runs. White agreed with him.
"Tell them if anything happens, you need the bionic legs. Six-million-dollar man."
But then Little asked the question that so many soldiers ask when they come through these doors.
"At this point you're pretty … certain I'm not going to die, right?"
White assured him in as matter-of-fact a way as possible, jokingly telling Little that he'd already completed his statistics for the month and that he's not about to change them.
"The guys coming in are going to be scared," White said. "You're not gonna lie to him. But at the same time you're gonna say to him, 'Look we're gonna do everything we possibly can.'"
White has served as an Army nurse for 16 years. Even though he worked in many military trauma centers in the United States, White said that the majority of the cases he sees are "your chest pains, your abdominal pains, your child fever works-ups." He added, "Nothing could ever prepare you for what you see here."
White transferred Little's treatment to Rick Rooney, a staff surgeon who would oversee his care in the operating room.