Sometimes one phrase may consist of several different meanings. You should choose whichever meaning makes the most sense for that sentence.
In the case of "If you are bugged out, please yell out for help", to interpret it as “如果你突然離開, 請大聲求救” or “如果你顯示出驚慌恐懼時,請大聲求救” would be illogical.
Everyone has different view about how he/she interprets a sentence; however, it needs to be within reason and within logic.
To me, it makes more sense and is more logical to translate it as 如果你感到煩亂時,請大聲求救.
http://idioms.thefreedictionary.com/bugged+out
bug out (slang)
1. to become upset and excited
變得煩亂激動
For example:
I said I would do it, and then I started thinking and I was kind of bugging out about the whole thing..