By Air Force Senior Airman Kevin Tanenbaum

NELLIS AIR FORCE BASE, Nev. — Air Force Maj. (Dr.) Charles Chesnut, a general surgeon assigned to the 99th Medical Group, said he was asleep in his bed at 10 p.m. on Sunday night, just like every Sunday before.

“About an hour and a half later, I was awakened by the Air Combat Command emergency notification system: ‘Avoid downtown Las Vegas – active shooter on the strip.’”

Chestnut, along with three general and three resident surgeons assigned to the 99th Medical Group, responded to the University Medical Center of Southern Nevada to help treat patients injured during the largest single-shooter massacre in modern U.S. history.

“Within two hours after the incident, all the resuscitation bays were full and six patients were being operated on by trauma surgeons,” Chesnut said. “Everyone worked together taking care of these patients and do some good in the face of evil. We treated over 100 patients, ranging from surgical procedures to end-of-life care.”

Working With Civilian Surgeons

The Air Force and civilian surgeons worked hand in hand through the night to treat patients’ visible wounds in the operating rooms while also addressing invisible wounds at the bedsides.

“We held their hands as they charged their cellphones so they could reach out to family members, who feared for their lives,” Chesnut said.

After a few hours, the doctor recalled, time blurred as the second wave of injured patients arrived around 3 a.m. from smaller hospitals that no longer had the capacity to treat them.

“The environment down there was controlled chaos, but the disaster response plan that the hospital had in place for a mass casualty worked,” he said. “At no point did I feel like our capacity was overwhelmed.”

As 7 a.m. approached, the influx of patients ended and the University Medical Center began to settle.

“Days like we experienced at UMC are the toughest ones, when you have multiple patients injured while multiple patients are continuing to come to the hospital,” said Air Force Col. (Dr.) Brandon Snook, a surgeon assigned to the 99th Medical Group. “Those are some of the toughest days, but also very rewarding. We all see a problem and do what we can to fix it to help out patients.”

-This story originally appeared on Defense.gov.