MONDAY, Jan. 27, 2020 (HealthDay News) -- A flight attendant on a recent commercial flight sent out the message: "Is there a doctor on board?"

An otherwise young, fit male passenger had suddenly lost the ability to move the muscles on the right side of his face, including the ability to close his right eye. He was drooling and had slurred speech.

Dr. Alan Hunter, who happened to be on the flight, answered the flight attendant's call. As he recalled, she informed him that the stricken passenger "was probably having a stroke."

Any in-flight medical emergency of the magnitude of a stroke "may require an unplanned landing, which disrupts travel plans and is expensive," noted Hunter, who recounted the episode in a case report published Jan. 28 in the Annals of Internal Medicine.

At first glance, the man certainly did shows signs of a stroke, but Hunter, who practices at Oregon Health & Sciences University in Portland, suspected something else might be at play.

The young man also complained of a sudden-onset headache and ear pain.

Overall, given the man's age and general good health, "his condition seemed consistent with acute Bell palsy," a sudden, temporary weakness of the muscles on one side of the face. Armed with the knowledge that the event wasn't a stroke, "I told the attendant that it was not necessary for the pilots to divert the plane," Hunter said in the report.

So what was causing the man's facial paralysis, headache and ear pain?

Hunter quickly ruled out some of the usual causes -- herpes infection, a tick bite, prior ear trauma or surgery. The man did mention that he was just getting over a head cold, however.

So Hunter said he focused on "the timing of event, which occurred during ascent," and the man's recent respiratory infection.

"I wondered whether declining atmospheric pressure [in the plane's cabin] might have led to a relative increase in middle ear pressure from a blocked eustachian tube," Hunter said. The eustachian tube is a tiny canal found in the middle ear, which can become blocked when infections strike.

Pressure building up from such a blockage might be "transmitted" to exactly those nerves responsible for the muscle function of the face, Hunter reasoned, triggering a temporary paralysis.

Acting on this hunch, Hunter asked the man "to breathe oxygen-enriched air and to perform maneuvers to relieve any excess pressure in his ears, such as swallowing and yawning."

It worked. "When I reassessed him after 15 minutes, his ear had popped and he was feeling better," Hunter said, and in just a few more minutes all symptoms had disappeared.

Hunter said this type of temporary paralysis originating in the ear is rare -- it's seen sometimes in scuba divers, for example -- but it typically resolves as soon as the ear pressure is relieved.

Dr. Andrew Rogove is medical director of stroke services at Southside Hospital in Bay Shore, N.Y. He read over Hunter's case report and said one key clue that the man was not having a stroke was that the muscles of the brow/forehead were included in the facial paralysis.

"This represented a peripheral seventh cranial nerve palsy, a Bell's palsy" and not a stroke, Rogove explained. "This astute observation avoided the need for the plane to land emergently, and he was also able to provide treatment to resolve this man's symptoms."

One other expert applauded Hunter's quick thinking at 30,000 feet.

"When confronted with patients who are experiencing concerning symptoms it's important for responders to understand symptoms that can be brought on by changes in cabin pressure," said Dr. Teresa Murray Amato, who directs emergency medicine at Northwell Health's Long Island Jewish Forest Hills, also in New York City.

"This is especially true when pressure-induced symptoms mimic life-threatening illnesses," such as stroke, she said.

More information

To learn about the key signs of an actual stroke, head to the U.S. Centers for Disease Control and Prevention.