I had, twice, before last night. The first time was about 40 years ago and I had just read all about it for the first time in my Sunday Times while awaiting Sunday lunch. We were then in the middle of lunch when my young son started choking and coughing and was in very real distress, having only just finished the article I knew exactly what to do and, having fortunately not absorbed the warning about young children, I gave him the most violent hug from behind. The pea which, was lodged in his breathing tube, shot across the room and splattered a green mark on the wall opposite.
The 2nd time was years later and, after a petanque competition, again a Sunday we were all enjoying a pub lunch in the open air. A rather portly member of our team began to choke and turn a funny colour, his loud heavings for breath drew attention as he dropped to all fours in a vain attempt to shift the obstruction.
In a most unseemly manner I came to him from behind, straddling his haunches and locked my arms around his ample stomach. A mighty heave with all my strength was most satisfactory as a lump of meat shout out of his mouth with a mighty roar. He soon recovered but was in pain and we later found out that I had broken 2 of his ribs. 
And then to last night. I have mentioned elsewhere that I returned home after a very good evening of meeting and eating, but then it was bedtime. Last job is to take my 3 and a half pills with a glass of water. The first, and largest, pill went onto my tongue as usual but then continued not to my stomach but straight down my windpipe, and got stuck there. I managed to calm the panic and breath in through my nose but I couldn’t shift it. So I reached for old Heimlich, but let me tell you it doesn’t work on oneself, not enough leverage with the arms clasped to the stomach but starting from the shoulders, they need to be behind the body altogether. So all I could do was breath in through my nose and then roar out of my mouth. It still wouldn’t shift. Recently, my asthma, with me from a very young age, has been producing phlegm deeper and closer to my lungs and so I have a bottle of cough mixture designed for such things. Don’t ask me how it goes down one tube while breaking a blockage in another, but it does. So I rushed for the bottle and took a mighty swig, then breathed in carefully to the absolute max before dropping to all fours and letting out a mighty roar, one that a pride of lions would have been impressed with.
The pill gave up and dropped to the floor. 
Just to demonstrate the body’s natural desire to stay alive, it produced excess amounts of phlegm, much more than usual, for an hour or so afterwards. So minor roars had to be employed for some time before I settled to sleep. And that is partly why Jules spent some time on my bed, his response always if he thinks I am poorly and he had already shown signs of distress during my struggle.
I am sorry if all the above has spoilt your Sunday mornings but if it saves a life one day, it’s worth it. 
mine’s only below my shoulders now, the chopped-off bit has gone to make wigs.
