Chris Hemsworth nearly died during Himalayan trek

Chris Hemsworth suffered "altitude depression" during a trek in the Himalayas with wife Elsa Pataky.

The 32-year-old actor is no stranger to action scenes as his alter ego Thor. But when it came to joining his spouse on a trip to the mountain range for a Spanish travel show, things went very wrong.

During an appearance on Jimmy Kimmel Live on Thursday night (14Apr16), Chris shared that the hike started off fine, but as he continued climbing he began to feel unwell.

"We ended up about 4,000 meters above sea level. You acclimate every couple of days, your body adjusts to the lack of oxygen and so on, and then you go higher and higher. And have you ever heard of altitude depression? I got that.

"Basically we went to 2,000 meters and then 3,000 and I slowly, honestly, started to kind of lose my mind. I was completely irrational - overly sensitive to the most trivial, silly, things. She (Elsa) was like, ‘What’s wrong with you?’ And I said, ‘Nothing, this is ridiculous, what are we even doing here, why are we here?’ "

Things came to a head when the team reached 4,000 meters above sea level, where they bedded down in some "rock huts with no windows", complete with dogs with rabies patrolling the camp, where temperatures were -30 degrees Celsius.

After venturing out to the tent toilet in the middle of the night, Chris returned to his bed where Elsa, 39, quickly noticed there was something drastically wrong.

"I get back in my bed and I’m just tossing and turning," Chris continued. "Elsa’s like, ‘What’s wrong with you?’ And I said, ‘I’m fine, I’m fine!’ And my breathing is getting worse and I start to (hyperventilate) - like Darth Vader meets Daffy Duck. And she’s like, ‘Something’s wrong with your breathing’. I said, ‘I’m fine, leave me alone, this is ridiculous, the dogs are barking, we shouldn’t be here, this is crazy’.

"She eventually ignores me, runs and tells the guides and they take one look at me and go, ‘Get him off the mountain’. And they start injecting me with all sorts of things, whatever’s going to adjust my oxygen intake and so on, oxygen mask on and fly down the mountain for eight hours in the four wheel drives."

While Chris was saved from permanent injury, he admits the next stage of altitude depression is even more dangerous.

"But apparently the oxygen was in my lungs, the next stage was oxygen in my brain and then good night - we wouldn’t be sitting here," he said. "Everyone else acclimated and for some reason I just couldn’t handle it!"