The dog spent a day and a half in the clinic's animal intensive care unit, she said.
Today Snoopy is fully recovered. "She's perfect. She loves everybody," Johnson said.
Sandy Garcia credits Johnson with saving Snoopy's life. "Without the CPR she would have been dead," she said.
Just as cardiopulmonary resuscitation or CPR can revive humans, it also can work, with some modifications, on animals.
Dr. Virginia Scrivener, of Animal Health Clinic of Funkstown, said she has given animal CPR instructions over the telephone to a pet owner in an emergency and has taught the technique to a 4-H dog club and middle school students in a pet first aid class.
People sometimes use CPR on pets who have fallen into swimming pools and on newborn puppies and kittens who are not breathing, Scrivener said.
Veterinarians rely on CPR if they begin to lose an animal during surgery, she said.
Scrivener said she even came across a Resusci Annie dog model, similar to the human version used to teach CPR, at an American Red Cross facility in York, Pa.
Although the thought of doing CPR on pets might make some people squeamish, when it comes to a life or death situation involving a beloved pet "I don't think many people are going to hesitate," she said.
Dwayne and Connie Simmers, of Waynesboro, Pa., used CPR on their 14-year-old Chihuahua mix Oreo after she accidentally hung herself over the side of their porch with her chain two weeks ago.
"We just did it. She'd been part of the family so long. I'd hate to see her go that way," Dwayne Simmers said.
"We've had her too long to let her go like that," Connie Simmers agreed.
Oreo was stiff, her tongue was hanging out and she appeared dead when Connie Simmers found her, she said.
Dwayne Simmers was carrying Oreo inside and petting her when he detected a faint heartbeat. "I thought maybe I could bring her back," he said.
So the Simmers alternated doing CPR on the dog, blowing air into her mouth, massaging her stomach and calling her by name, Connie Simmers said.
Oreo began kicking and "she came through," she said, although for a while the dog couldn't stand up and didn't seem to know her name.
The Simmers immediately took Oreo to her veterinarian, Dr. Noelle Weeks at Wayneboro (Pa.) Veterinary Clinic, Connie Simmers said.
Oreo "seems to be doing great now (although) she seems to be leery about going out," Connie Simmers said.
Weeks said that Oreo would have died from the hanging had she been wearing a choke collar.
Because the Simmers' didn't check the color of Oreo's gums Weeks said she is not sure how far gone the dog was when they found her. Blue or gray-colored gums indicate that no oxygen is reaching the brain.
Generally animal CPR involves blowing air into the snout, which is easier to seal than the mouth, but the Simmers' managed to stimulate Oreo's breathing by blowing air into her mouth, Weeks said.
A Tavares, Fla., company, Pet Love Productions, is marketing a video for about $40 instructing people how to do pet CPR and first aid.
Weeks, of the Waynesboro Veterinary Clinic, advises that it is best to "learn it from a veterinarian or a trained veterinary technician ... It's a lot different than for humans."
The technique can vary with the size and kind of animal, she said.
Dr. Jeff Ott, of Franklin Veterinary Associates outside Greencastle, Pa., said CPR "is not a particularly practical thing to do in the pet kingdom. I think a much more practical approach would be to educate people when not to do CPR."
For instance an animal hit by a car, even the most tame pet, "will try and bite the first person that comes to them. They're hurt and in shock," Ott said.
Animal CPR is "totally impractical for the average person," he said. "My personal opinion is it will probably get them into more trouble than it's worth."
However, Ott makes one exception.
There are relatively easy techniques that people can learn to stimulate respiration in newborn puppies and kittens that are in trouble, such as clearing their mouths, vigorously rubbing them with a dry towel and holding the puppy upside down and swinging it between the person's legs, he said.