Bob R has an excellent documentation of this long-term, overlooked early signs of HAPE in an account of a Denali expedition. One of the participants became lethargic over time and I believe that he even had a slight cough; the others misinterpreted it as failed conditioning (if I remember correctly)
Here you go. It's in Bob Rockwell's web library:
Ordeal on Denali Notes by the members of the CLMRG 1992 Expedition
It's 20 pages of intense reading! Mention of the developing HAPE condition begins near the end of the 9th page:
We were all tired from the effort of the 2500' gain. But, after retrieving the cache, Tom was surprisingly fatigued. We didn't know it at the time, but this was the beginning of a major turning point in our expedition.
It's a harrowing story. Close calls, dangerous falls, narrow safety margins, frostbite. Things could have easily turned out far worse.
Bottom line, though, is that HAPE can creep up on unsuspecting parties. With dangerous results.
keywords: Rockwell Denali Expedition HAPE
