When I was in grad school at UCLA, my department and lab were in the Medical School, housed in the UCLA Hospital complex. The front half of the building was hospital, and back part was a warren of labs, offices, classrooms, library, vivarium, etc.
One day, I was standing in the hall outside my lab, when I saw one of the post-docs from up the hall frantically waving his arms, and putting his hands to his throat - I recognized the universal sign for choking, but I was afraid I wasn’t going to be able to perform the Heimlich maneuver on him (he was taller than me), and after dithering about what to do for a couple of seconds, decided to run in the opposite direction through the double doors to the hospital to find someone who would for sure know what to do.
Just then, someone else from another lab came up behind the guy who was choking, performed the Heimlich a couple of times, and out popped the apple skin he was choking on.
A day or so later, I was shopping at Safeway, and the paper grocery bags had directions for how to do the Heimlich on them, including how to do it on little kids and babies. I read it carefully, ashamed that I didn’t feel capable of helping the guy.
That weekend, my father came over, bringing his delicious spareribs - my daughter, who was ~18 months old, was a sparerib hound (that girl can STILL put away an amazing amount of meat). There were several of us sitting around talking, when I became aware out of the corner of my eye that Jess was choking and freaking out. I immediately reviewed what I had read on the bag in my head, but decided to try first to turn her upside down to try to dislodge the chunk of meat she was choking on - but no go. So I turned her over and using my fingers (rather than fists) like the instructions suggested, jammed them up under her ribs to try to force air out of her lungs without shattering her little ribs - and out popped the meat.
I had meanwhile already been considering if I could cut my daughter’s throat and stick in a straw or outer tube from a ballpoint pen (something I’d seen on an episode of MASH), while getting someone else to call 911 if that didn’t work - but I wasn’t sure I could do it at all, much less correctly.
I gave her a hug, then quickly handed her over to someone else and ran to my bedroom where I burst into tears.
She didn’t get to eat spareribs directly off the bones for a long time after that.