After some testing I believe I'm able to replicate this.
Smoke a Unicorn Dream (this does not seem to happen with 'regular' cigarettes)
Put on a Pressure Suit and Pressure Suit helmet (have not tested with EVA)
After feeling Flushed and Unwell the character will then get the Blacking Out status, however they will not go unconscious.
There are no other reasons for Blacking Out to occur, and it looks like the issue is benign? It could be on purpose but I figured I'd report it.