If you think ischemia is bad, there is also something called reperfusion injury. Basically, if the lack of oxygen does not kill a cell directly, the spike in oxidative stress when the oxygen supply returns can cause it to become inflamed or even initiate apoptosis.

This is why medically induced hypothermia is sometimes used on heart attack patients, so that the brain doesn't swell up and kill itself after normal oxygenated blood circulation is restored.

So let's not casually mess around with air passengers' oxygen supply, mmkay? It would almost be better to just flood the passenger cabin with vaporized marijuana extract. The risk there is that someone might stage a fake attack just to turn the plane into a giant bong.