Mark McKenna and his wife have two cute dogs named Shredder and Coco.

McKenna said the two are best friends who love to swim together. And that's exactly what they were doing last Friday. On home surveillance video, you can see Shredder and Coco playing in the water. But then, Shredder got a little too rough with Coco and held her under water for more than 30 seconds. McKenna then saw what was happening.  

"When I returned, Coco was underwater floating," said McKenna. "I pulled her out of the water, she was lifeless."

He immediately adminstered chest compressions and CPR.

"It was scary," he said.

But after more than a minute, he was able to revive the dog.

"Took her to the vet, everything was fine," he said.

Officials with the Orange County Red Cross, who teach pet CPR classes, said if McKenna hadn't acted so quickly, the dog likely would have died.

Patty Whit, Red Cross Health and Safety Director, said a pet owner knowing how to treat an injured animal before they get to a vet, can make a difference in life or death. In the case of animal CPR, she said it's very similar to administering it to a human.

"It's still chest compression, it's still breathing, it's mouth to snout," Whit said.

McKenna said it's been three decades since he took a CPR class.

"Thirty years and it all came back to me," he said.

Still, he said he's now ready for a refresher course.