He took the captain’s chair, intubated the man, administered a second shock and started an IV. A third shock brought back a pulse.

It took 45 minutes for the ambulance to arrive at the hospital. Once doctors took over, Greenough watched as the American man’s family tried to figure out how they would come up with $35,000 for further treatment. The man needed two stents and a pacemaker.

Later, the family told Greenough that their father also had gone into acute kidney failure and fought pneumonia. But the man is doing much better now and is expected to recover.

Once things cooled down at the hospital, Greenough still had to figure out how to get back to the hotel. His money was with his wife, Rebecca, back at the resort. And, again, he didn’t speak any Spanish.

“I’m standing there in my robe in the middle of Mexico with no shoes and no idea what’s going on,” he said.

A receptionist called a taxi, which broke down about one-third of the way home. A replacement taxi brought him back to the resort, where he had to convince guards of his story — again using mostly hand gestures — and stall the cab driver until his wife just happened to walk past the front desk to pay for the ride.