That long thread has a lot of good info and some questionable opinions. My cardiologist many years ago had me go through a sleep study and they found serious sleep apnea where I stopped breathing for periods of time, many times per night. This condition can lead to heart disease or make heart disease worse.
The brand and model of CPAP machine that I use, is designed to run directly off of a 12 volts DC as well as 120vac. The 12 volt cord plugs into a receptacle in the back of the unit. Many CPAP units will not run directly off of 12vdc battery and are designed to run off a special portable battery and 120vac inverter pack. Check carefully on 12 vdc (camping/emergency power) option, before buying a CPAP device. Removable heated humidifiers require 120vdc power and draw heavier current. I have never needed to use a humidifier.