On the Road With My CPAP Machine

I’ve just returned home to Germany from a 10 day trip to Los Angeles. I took my CPAP machine with me and it was absolutely no problem.
At the security checkpoints, all of the agents knew what it was and no one blinked an eye. I didn’t need to show the small ID card I received from the hospital.
The CPAP machine worked instantly when I plugged it into the electrical outlet in L.A. with an adaptor. I didn’t miss a night, except for the time on the airplane.
My doctor told me that there is a CPAP machine that runs on batteries that one can use on an airplane, but I’m not sure if I’m ready to freak people out with a mask that looks like an oxygen mask on a long flight.