High-altitude flights and destinations: Such a headache

Question: Two years ago, I traveled to Tibet, including Lhasa at 11,975 feet above sea level. I started having mild headaches. Two weeks later, as the plane was landing in San Francisco, I became non-responsive. I underwent a craniotomy to relieve pressure from a clot next to my brain. I’ve had other altitude issues, including passing out while snowshoeing near Mammoth and experiencing altitude sickness after leaving Cuzco, Peru. I know commercial flights are pressurized above sea level, and I have taken some domestic flights. Is a long flight safe for me?

George Fisher

Playa del Rey

Answer: You could argue that it’s unsafe to walk across the street, and you’d be correct, but with a series of medical events like Fisher’s, the best move is to check with a physician who knows your medical history.

The blood clot and altitude issues may not be related, two doctors I spoke with said. If that’s the case, they think he probably can travel safely in an aircraft for a longer period of time. If you sense there’s a “but” coming, you’re right.

First, though, let’s talk about what happens when you fly. Commercial aircraft generally are pressurized to between 5,000 and 8,000 feet. That means you will feel just as you do when you’re in Santa Fe, N.M.; Park City, Utah; or even Big Bear. If you have a headache when you get off the plane and feel out of sorts, you may be experiencing the effects of decreased oxygen. (On the other hand, who doesn’t get a headache and feel out of sorts when dealing with air travel on certain carriers? And, yes, airlines, you know who you are.)

As long as he’s healed from the surgery, Fisher’s history probably won’t preclude international flights.

“I think you can do it [fly for long periods] fairly safely,” said Dr. Charles D. Ericsson, head of travel medicine at the University of Texas Medical School at Houston. “I don’t think anyone can give you a 100% guarantee, though.”

The biggest red flag, in fact, may be a person’s previous reaction.

“The most significant risk factor for altitude sickness is previous altitude sickness,” said Dr. Tanvir Hussein, a Los Angeles-area cardiologist.

“If he were my patient, I would advise him against further high-altitude kinds of activities.”

Ericsson also noted the difficulties of traveling to a high-altitude destination — for anyone — without acclimatization. “If [the traveler] has the opportunity to take time and stage an ascent over days — most people don’t have that time — it’s better,” he said. “If you fly in to a place — boom — you’re there at 12,000, and you can have shortness of breath” and other symptoms, he said.

That means if you’re headed to El Alto, Bolivia (13,615 feet), near La Paz, or Xigaze (12,585 feet) near Lhasa, you might feel more than out of sorts. Doctors often prescribe Diamox to aid with the acclimatization process.

But a plain old plane trip? It might be dangerous, but probably more so to your psyche or your wallet than to your health.

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