
In the 2021 Netflix documentary 14 Peaks: Nothing Is Impossible, elite mountaineer Nirmal Purja races up the world’s highest summits at extraordinary speed. But even he isn’t immune to altitude.
During one ascent, Purja develops symptoms of high-altitude cerebral oedema (brain swelling), a dangerous form of altitude sickness that can strike with little warning. It’s a stark reminder that when oxygen levels fall, no amount of fitness or experience guarantees protection.