Nikolaus Netzer1,2, Riccardo Stoohs3. 1. Hermann Buhl Institute for Hypoxia and Sleep Medicine Research, University Innsbruck, Bad Aibling, Germany. nikolaus.netzer@uibk.ac.at. 2. Institute for Mountain Emergency Medicine, Eurac Research, Bolzano, Italy. nikolaus.netzer@uibk.ac.at. 3. , Dortmund, Germany.