CPAP machines are allowed on board:
https://www.lufthansa.com/online/myp...en&cid=1000390
Traveling with other assistive device
Lufthansa will accept assistive devices with batteries as checked baggage as well as inside the cabin. Assistive devices with batteries include respirators, CPAP machines (Continuous Positive Airway Pressure machine), portable oxygen concentrators (POC) and ventilators. Traveling with a POC requires a physician statement. Lufthansa will allow qualified individuals with a disability who are using FAA approved personal respirators/ventilators to bring their equipment, including non-spillable batteries, onboard the aircraft. You must have sufficient battery power for 150% of the maximum flight duration.