LOUISVILLE, Ky. (WHAS11) – The men and women who work inside University Hospital say when it comes to responding to a disaster, they function on the idea of not "if" but "when".

They use practices and drills to prepare for a disaster like Las Vegas multiple times every year.

"It’s something that we've always planned for but the planning and the training has taken on a bit more seriousness,” Timothy Price, Associate Professor of Emergency Medicine at U of L, said.

"As best you can, we try to train and drill and have protocols in place”, Matthew Benns, a trauma surgeon and associate professor of surgery, said.

"We know what needs to be done to get the job done,” Josh Goss, Emergency Manager for U of L Hospital, said.

As the only level one trauma center in the area, U of L Hospital would be the heartbeat of any emergency operation involving mass casualties in Kentuckiana.

"We're always on heightened alert for the various events in the city- Kentucky derby, etc. There's always a possibility for things like that,” Benns said.

They work with EMS, LMPD, Metro Safe and other agencies to ensure all response would be coordinated and effective. As during these situations, every moment counts.

Staff said the last time they worked in disaster mode was during the 2012 Henryville Tornado when the hospital taking on dozens of critically injured patients.

Nearly every day they say they treat a gunshot victim who requires the type of urgent operation and action that would be necessary in the event of a mass casualty situation.

Benns said, "Even in those smaller circumstances there is an all-hands-on-deck approach."

The operation starts on site with an EMS provider tracking transportation and directing who's going to which hospital and why. That's also where they start to triage patients based off their injuries.

The most critical would be taken to University's emergency room... straight into the trauma center named "Room Nine".

"In the setting of a mass casualty you want to be able to flex your capacity”, Keith Miller, assistant professor of surgery and trauma surgeon, said.

The worst of the worst are taken to U of L’s Emergency Room but in the case that hundreds are hurt, other hospitals would open their ERs to critical patients as well. Surgeons who specialize outside of trauma would also step up to treat patients with life-threatening injuries.

The doctors say they would stretch their resources as far as they could- including ambulances, material and staff. Then they would look to surrounding counties and then nearby cities for additional resources if they need them.

It’s a process they have practiced time and time again.

“Always asking the question- what would we do if the worst-case scenario happened here,” Benns said.

The doctors also said people at home should be ready for a mass casualty disaster. One way would be training in their program called "Stop the Bleed".

During that program, the surgeons teach civilians techniques to stop someone from bleeding out on the scene of a mass causality.

They also encourage people to donate blood during emergencies to help keep supplies stocked.