The mass shooting on October 1 in Las Vegas that killed 58 people and injured close to 500 has put a spotlight on the role of first responders, including the staffs at hospitals and trauma centers. Las Vegas, like other American cities, has a plan in place to not only address which facilities will handle which trauma cases but also how they will coordinate during large-scale incidents. Complicating the job is the fact that the definition of “large scale” has expanded in recent years, says Ian Weston, executive director of the American Trauma Society (ATS).

“Years ago, in the pre-9/11 world, hospitals were preparing for an influx of maybe a dozen patients at time, or two dozen patients at a time,” he says. “And it was what the hospitals would treat off the street—a bus crash or a car crash. Little did they prepare for active-shooter scenarios, or cases where somebody would just go in and shoot up a mall or movie theater. Hospitals have had to adapt tremendously to prepare themselves to treat large numbers of patients with penetrative trauma, with stab wounds, complex injuries that require a great deal of attention.”

ATS, which serves physicians and other healthcare workers, helps design protocols for trauma centers and ensures that they’re in compliance with state and federal regulations. ATS is operated by an association management company—ASMI—which also runs the International Association of Emergency Managers, and the two organizations work together to design training resources and models for trauma centers. One focus in recent years, Weston says, is on handling incidents within the facilities themselves.

“It used to be every couple of years they’d revisit [the protocol] and see if it was still valid,” he says. “Now it’s sometimes annually, sometimes a couple of times a year, that they’re planning and preparing and training to respond to this type of incident.”

These days, ATS’ work goes beyond helping to train the staffs at the approximately 2,000 trauma centers in the United States. The association has also reached out to the general public about how to play that role. Every May, ATS collaborates with the Society of Trauma Nurses to promote National Trauma Awareness Month, which in past years has emphasized prevention in terms of distracted driving, sports injuries, and similar incidents. This year the theme was “Stop the Bleed,” based on a program launched by the U.S. Department of Homeland Security in 2015 and designed to empower non-physician first responders and everyday citizens to perform life-saving acts like using tourniquets and delivering CPR.

“While our main focus is trauma centers, it also incorporates a bit of an injury-prevention component,” Weston says. “We’re trying to promulgate the message of empowering citizens as first responders to deal with injuries that you would see in incidents such as these and how to treat their fellow man.”

Such programs have had an impact: In 2016 Kaiser Health News reported that the use of emergency tools, such as tourniquets, has increased among police officers, teachers, and EMS technicians. “We know it’s saved a lot of lives throughout the country,” says Weston.