I'm 28 and have been put under with anesthesia over a dozen times, whether surgery or medical tests. I have only had a reaction once when I aspirated, I vomited while under and flooded my lungs. I almost drowned. It wasn't because of the anesthesia, it was because of my condition, my digestive system was slow. They tell you not to eat for 12 hours before surgery, and I didn't, but when they put me under, BAM.