The Heimlich Maneuver (named after the doctor who invented it), is a way to dislodge food from someone's throat when they are choking to death. You stand behind them, wrap your arms around their abdomen, make a fist, and thrust upward several times. This should cause the food or whatever is blocking the throat to pop out.
I'm a nurse, but I have never heard the maneuver used as a verb. We say"performed the Heimlich Maneuver." However, unless this is some kind of slang that I don't know about, there should be very few times when you would need to use the word.