My husband was extubated and died later that day. He was in multisystem failure due to his lymphoma. He did not wake up, I believe he had been oxygen deprived, he most likely threw a clot and had a PE, a side effect from his chemo. He wasn't supposed to have been intubated in the first place.
They remove the tube and then put them on a mask, I think they put him on a non-rebreather. It's pretty simple, but terrible and sad.