Jaze, I learned it by observing others. Some people had brought a passed-out dude to the drug hotline I was volunteering at, instead of doing the smart thing and going straight to the ER or the smarter thing of calling an ambalance; this ice-cube thing was what the more-experienced volunteer did as a matter of course. I only got to drive. :~) I found out later that the ice thing is a help while waiting for the paramedics to arrive.

~S~