Dr. Keith Murray was helping his 3-year-old son get ready for a costume party on Saturday morning when he saw a phone alert he couldn’t ignore.

He kissed his wife and kids goodbye, unsure if he’d return. There’s an inherent risk to being both a UPMC Mercy trauma doctor and member of the Pittsburgh SWAT team.

His wife worries, but she understands why he does it: for the guys, for the SWAT team. “To give them an extra chance to get home to their families should they get injured,” Murray said. “On Saturday, that worked.”

Murray got into his truck at about 10 a.m. and raced from his Fox Chapel home for Tree of Life Synagogue in Squirrel Hill, where an active shooter was reported.

The drive to that part of town normally takes 16 minutes. It took less that morning, and the 42-year-old Murray admits he probably broke some traffic laws.

He stopped his truck in the front yard of a house near the synagogue. He spotted a fellow SWAT officer and together they sprinted toward the place of worship.

This is the part when Murray turns off his emotions. He talks about how he was trained for moments like this. During drills, SWAT teams respond to scenes where mannequins are covered in fake blood and brains. They prepare for mass casualties and bombs. They train for what they might see.

“Was it horrific inside the synagogue? Yes. Are we trained for that? Yes,” Murray said.

He identified 11 people dead at the scene, knowing he couldn’t help them. The trauma doctor focused on who he could save.

Murray saw an elderly couple hiding in a corner and helped usher them to safety. In the main sanctuary, he saw five bodies initially and noticed one was alive. She was in shock and shot in the arm. Murray applied a tourniquet, turning the second floor of the synagogue into a triage unit. Dr. Lenny Weiss, a UPMC doctor who lives near the synagogue, also went to the synagogue to stop blood loss and save lives.

A floor above them, a shootout raged between SWAT officers and the killer.

One SWAT officer was shot seven times and critically injured.

“He was bleeding everywhere from multiple wounds,” he said.

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The doctor applied a tourniquet to control the bleeding, one of the most important parts of trauma training. “It saved at least two lives Saturday,” Murray said.

The critically wounded officer had three or four broken bones and has needed three or four surgeries since being shot seven times. He has a long recovery ahead, but he has no life-threatening injuries, Murray said.

That’s the value of having a tactical EMS team with SWAT officers and being able to respond quickly.

“You want to be as close to the point of injury as possible,” he said. “It’s the difference between life and death.”

Murray and the other UPMC doctors at the scene and in the trauma centers saved lives, even while their own were at risk. This is what it takes to save as many people as possible in an active, mass shooting, they said.

“You have to go into environments like that and shut down your entire emotional side,” Murray said.

At least until the scene is cleared.

Murray walked out of the synagogue after the scene was considered safe.

“I talked with the SWAT team. We debriefed on whether there was anything we could have done better,” Murray said.

And then somehow he had to get back to the morning that began with helping his son get ready for a costume party. He had to pivot from family life to an act of terrorism and back to family life. Murray needed to find a way to “get back to normal.”

“That’s the part they don’t train you for,” he said.

Yet, he’s managed to do it several times, responding to about 60 percent of all Pittsburgh SWAT calls in a year. This one at the synagogue was different.

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“It was more severe,” Murray said.

He was working on getting back to normal as he walked to his truck parked in someone’s front lawn. A family of four stopped him on the sidewalk.

“They said, ‘Thank you for what you did,’” Murray said.

That got to him.

“That was emotionally impactful," he said.

He got in his truck and drove back to his empty house in Fox Chapel, with his wife and children at a costume party. That time, the drive took the normal 16 minutes. Maybe a little longer.

“Thankfully, when I went home, my family was not there,” Murray said. “They didn’t have to see me wash the blood off.”

He opened a beer, stood in the shower for about 20 minutes and tried to wash away the morning during the quiet hour he had at home.

When his family returned, he hugged his wife and kids again. Their children, who are 3 and 5 years old, wanted to know what happened that day.

They know when their dad leaves quickly like he did that morning, it means something happened. They know their dad is a doctor and also works with police.

Murray faced his next challenge, trying to safely explain trauma to young children.

“Some people got hurt, and daddy tried to help them with his police friends,” he said to his kids.

He knows they are “so young,” and he chooses not to tell them much. Instead, he kept their day as normal as possible, enjoying one of their favorite parts of a Saturday afternoon – cooking dinner together.

“What’s your secret ingredient?” one of his children asked.

“Love,” Murray said. “I think we need more love in the world.”