Answer:
It takes very little to to lose oxygenated blood to the brain.
Step-by-step explanation:
Breathing does two things: Intake of oxygen and removal of carbon dioxide. If there is a respiratory emergency, for example, and overdose victim stops breathing, the carbon dioxide can build up, damaging parts of the brain, leading to forgetfulness, headaches, nausea, amnesia, fainting, brain damage, both minor and major, and in extreme cases, death.