Apparently the device simply let go as Obama opened his mouth to answer his first question on '60 Minutes'...
The defibulator, whose existence was revealed for the first time on the Tonight Show with Jay Leno, is a seldom-used device in the Obama White House, and apparently its capacity had not been upgraded to meet the demands of the new Administration.
White House Press Secretary Gibbs was later quoted as saying, "Tee-hee, maybe it was Rush Limbaugh, snicker..."