The stuff in whipped cream cans is nitrous oxide, more commonly known as laughing gas. It creates a buzz which some people say is like a feeling of ultra strong poppers. The stuff in cans of compressed air is much more harmful and addictive, and they and can cause hypoxia, paralysis and other serious issues. I guess we have to wait for the autopsy but I wouldn't be surprised if he died due to passing out in the bath from the effects of the inhalant abuse of the compressed air, which is also called 'dusting'.