Far as I know self test meters don't have altitude sensors, the invalidation will be due to air pressure rather than altitude per-se, and this will be weather-dependent - I'd be trying to get an idea of what air pressure invalidates it and keep a close eye on that.
I am assuming you've already done some high-ish altitude training (presumably without problems) for this somewhere closer (e.g. the alps), assuming you've tested while doing that, that should give you an idea of how, and how much, your INR reacts to altitude. So you are probably in better position to judge with more data, specific to you, than anyone else.
Not sure testing is going to be the biggest issue at end of the day, risk of altitude sickness / pulmonary oedema / HAPE probably will be. Last time I looked, most if not all of the prophylactics & treatments for altitude sickness were contraindicated on warfarin, if still true, that could be a big problem.
You can get altitude sickness in the Alps, but you can also be helicoptered back down within hours, in Nepal... well, good luck. Only live once and all that.
I'm assuming you've had approval from your doctors, what did they say?
[I know what mine said, but we're all different and have different doctors...].
Consultant is ok for me to go, just to stay really hydrated and to self test due to diet change, rather than altitude related.
Have been up to 4,950 and above 4,000 a couple of times, no issues, but this was prior to starting warfarin.
I’ve also got contact at hospital in Kathmandu for test before I set off and for when I return.
Additional insurance purchased to include APS, and for helicopter evacuation.
I’d also agree that the device reliability is related to air pressure at that altitude, and that finger prick blood will coagulate far quicker once exposed, therefore giving unreliable reading.
Plan is to reach out to consultant with my plan and to check on those three or so days when I can’t guarantee accuracy of meter….
Content on HealthUnlocked does not replace the relationship between you and doctors or other healthcare professionals nor the advice you receive from them.
Never delay seeking advice or dialling emergency services because of something that you have read on HealthUnlocked.