If you’ve been in a terrifying situation when you see someone choking, having the knowledge of what to do can literally make a life or death difference. A few years ago I wrote about the time I was walking home from work, past a baseball field and a woman waved to me as she signaled that she couldn’t breathe. Somehow the basic skills I’d learned as a Boy Scout almost 30 years ago had stuck with me. The universal sign for choking is hands clutched to the throat. If the  ...