Not a medical professional but my grandfather was dying from cancer that had made him septic. He'd had some kind of abdominal surgery (I was very young I dont remember those specifics) but it was so mutilated in there that he was basically rotting while alive. They couldnt stitch him back up so they just packed him and left him open on major pain killers. He kept begging for more drugs. The worst moans I've ever heard. Finally a nurse said she'd gotten permission to give him a very high dose of morphine but that he probably wouldnt be concious again before he passed. My dad made an executives decision to go ahead and give him the drugs. About 15 minutes later, my grandpa shot upright and grabbed my Dads hand, eyes wild and said "I'm flying son! I'm flyin!" Sunk back onto the bed and was passed a few hours later.