There's new technology that automates this and the incident of rib-breakage is, as I understand, drastically minimized. (http://en.wikipedia.org/wiki/AutoPulse)
As an anecdote, my 70+ year old dentist (i.e. not the demographic with the strongest bones) had a heart attack (clinically dead). The responding EMTs used the AutoPulse, which saved his life. It pumped his heart for 10+ minutes while 1 EMT gave him air and the other drove to the hospital. No brain damage, no broken ribs.
There's new technology that automates this and the incident of rib-breakage is, as I understand, drastically minimized. (http://en.wikipedia.org/wiki/AutoPulse)
As an anecdote, my 70+ year old dentist (i.e. not the demographic with the strongest bones) had a heart attack (clinically dead). The responding EMTs used the AutoPulse, which saved his life. It pumped his heart for 10+ minutes while 1 EMT gave him air and the other drove to the hospital. No brain damage, no broken ribs.