Liam, an ailing silky terrier, had just gone home after being treated for pancreatic disease. Late Friday night, his family’s house in Kensington lost power. Liam started panting, and the refrigerator containing his medication began warming. So Gina Bohrer scooped him up and took him right back to the Greenbriar Veterinary Hospital in Urbana.

The next morning, Jennifer Revroad showed up with eight overheated Saint Bernards, including a puppy with an injured leg. Her rural home in Laytonsville had lost both power and water — and her rescued “saints,” as she calls them, drink at least a gallon each day. Somehow, the clinic found room for them all.

“The storm turned us into a MASH unit for pets,” said Jessica Finnegan, Greenbriar’s manager. Vet clinics from Annapolis to West Virginia, which had also lost electricity in Friday’s violent storm, sent heat victims and other emergency cases there. By Sunday, all 450 boarding and hospital cages were full, and staff members were checking each occupant every 15 minutes for signs of overheating.

As the Washington region sweltered and suffered through a massive power cut during one of the hottest weeks on record, its vast domestic pet population — especially the fatter or furrier varieties — sweltered and suffered, too. A handful were injured in the storm or suffered from smoke inhalation from fires ignited by lightning, area veterinarians said, but hundreds of thousands were left in homes with no way to keep cool.

Desperate pet owners swamped phone lines at kennels, pet-friendly hotels and doggie-day-care centers.

In Shirlington, the shop Dogma invited all pets to come and chill out for the day. At Dogtopia, a boarding and play facility in Herndon, staff members filled plastic baby pools for splashing and kept fans running around the clock. They had expected about 20 dogs to board for the weekend — and got 65.

One of the eleventh-hour visitors was Smoky, an 18-month-old husky-malamute who had recently moved to Virginia from Texas. His owner, Duane Edghill, said he had already brought Smoky — thick-coated for arctic winters — to Dogtopia for a summer haircut. But by the weekend, the heat was unbearable and the dog was miserable.

“He needed somewhere to play and cool down, too,” Edghill said. “In Texas, he used to swim in the lakes and rivers. Here, he was enjoying the cooler weather, at least until Saturday.”

Some homeowners moved their families — pets included — into hotels to wait out the power crisis. The Washington area has more than two dozen hotels that accept pets, and despite the hefty room fees, several of them were sold out last weekend. “We had a lot of heat refugees and a much higher pet occupancy than usual,” said Erin Adam, a manager at Residence Inn in Bethesda.

For pet owners who cannot afford special facilities, a cool, dark basement would work just as well, veterinarians said. They recommend keeping dogs as quiet and calm as possible, making sure they have access to fresh air and water, and restricting their walks to the early morning and late evening. For those who become too hot, it’s important to cool them off gradually with a wet cloth or cool water, but never with ice, veterinarians say.

“One guy called and said he had just thrown his dog in the freezer,” said William Amoroso of Falls Road Veterinary Clinic in Potomac. “He asked me what to do next. I told him to take the dog out immediately, but it was already dead.” Unlike people, Amoroso said, dogs breathe heavily in order to keep cool, so a good air supply is critical.

Fred Jones of Arlington Animal Hospital said the most important advice for helping pets during the power shortage was to “use common sense.” No Frisbee games at the dog park and frequent checks to make sure the water bowl is full. Mostly, he said, what keeps a human cool will also keep a dog cool.

At Greenbriar, Matt Benedick said dogs and cats that are overweight, snub-nosed or very furry are at extra risk in extreme heat. Most cats, though, seem to adapt well, in part because they are sedentary during the day. One of Amoroso’s few feline patients last weekend was an elderly cat that had been sleeping on a bed Friday when lightning struck the house. The terrified animal leapt off and broke a leg.