I took my 7 y/o from 1000 ft (where we live) to 11k this weekend. We overnighted at 5k in western KS, then drove to the unit, fished for a bit at 9k, and then went to 11k that afternoon. Everyone in the party was feeling it, headaches, etc. I drank a ton of water on the drive and tried to make my boy do the same, although he could have drank more.
After a relaxing afternoon/evening, at about 1 AM he woke up and threw up his dinner. He does that sometimes if he has too much sugar, which he tends to do on camping trips. I wasn't sure how much sugar he had. He was complaining of head ache. No other symptoms that I could tell, but made the call to head down. We stayed the night at 8k, I did some in depth reading on altitude sickness, bought one of those Boost Oxygen cans, and decided to go up the next day.
He was taking breaths from the can every 15 minutes or so, and we had another good/relaxing afternoon and evening. Same deal that night, he threw up his dinner. Decided just to ride it out. Next day he was fine, went hiking, and we stayed the next night much lower.
Based on this experience I have made some conclusions:
1) There are 3 types of altitude sickness, and you need to know the differences.
Traveling to a place at a higher elevation than you're used to can make you sick. Learn the symptoms of altitude sickness and what to do if you get it.
www.webmd.com
Acute Mountain Sickness (AMS) is what most of us are familiar with, headache, nausea, vomiting, etc. This is not as concerning as it is annoying.
HAPE (high altitude pulmonary edema) is serious, and can be identified by the fluid in the lungs, you might be coughing it up. You need to go down if you experience this.
HACE (high altitude cerebral edema) is serious, and can be identified by confusion, trouble walking, etc. You need to go down if you experience this.
2) With kids, I will spend a day or two camping lower (like 9k) but recreating higher. I don't mind the 20 minute drive up if we can save some trouble.
3) I will try to be more diligent about making sure we're all well hydrated days before the trip.
4) I will keep on hand a Boost Oxygen bottle, more of a just-in-case kind of thing, and for warm fuzzies. I have no illusions it can really treat or prevent altitude sickness, but it emboldens me to trust my gut to ride out a bout of AMS instead of throwing in the towel and heading down.