Eric,
Excellent post... I wish I could have been a fly on the wall when your ex neurologist said high flow rate oxygen therapy would give you headaches and cause oxygen saturation...
That has got to be a classic... I'm glad no neurologist ever told me or the rest of the pilots in the squadron while we flying Navy fighters and breathing 100% oxygen at flow rates over 40 liters/minute... that it was bad for us... and all the other Navy and Marine Corps pilots who have been doing the same for over 60 years while flying tactical aircraft... We would have float checked him on the spot or sent him back to stupid study for a refresher in aviation physiology...
Ctech... Call your doc and ask for a new Rx for O2 with a higher flow rate of at least 15 liters/minute...
Use the info in the following link when you call your doc for the oxygen Rx:
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At best, a single E-size oxygen cylinder will be good for 3 aborts... Although I seriously doubt you'll be able to achieve an abort at 5 liters/minute... That low a flow rate will cause your CO2 level to spike and you'll start having anxiety and panic attacks in less than a minute using a non-rebreathing mask. In short, the excess CO2 will prevent an abort with oxygen at that low a flow rate.
Here are a couple suggestions... Get the biggest industrial hefty trash bag you can find and use some duck tape to seal the open end of the trash bag. Then cut the tip of one corner on the closed end of the trash bag, un-tape the 1 liter reservoir bag on your disposable non-rebreathing mask and replace it with the hefty trash bag... That should give you a 20 to 40 gallon reservoir bag. Place your finger inside the non-rebreathing mask to hold down the inlet check valve while the reservoir bag fills with oxygen. Once it's full, fold the bag over the nipple at the bottom of the non-rebreathing mask an put a rubber band over it so it's charged and ready to go for your next attack.
When that attack hits, remove the rubber band, put the mask on your face and breathe the oxygen as fast as you can comfortably breathe it.
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The other option is to hyperventilate on room air for a minute inhaling and exhaling as fast and as deeply as possible, then relax and suck in the oxygen until the reservoir bag collapses. Breathe room air while it refills then suck the reservoir bag empty again 4 or 5 times. At that point You'll need to hyperventilate on room air and suck the reservoir bag empty several times in order to achieve an abort.
Good luck and take care,
V/R, Batch