Counter-rotation, only about half (or less) of those patients ambos perform cpr on walk out of hospital. Many times the paramedics keep them going with drugs, defib and cpr, but they have underlying medical conditions that they do not survive. When cpr is performed by non-medical personel the figure is pretty low. 10% might be right.
I know my first attempt at cpr on a real person as a young and proud first-aider was not successful and it bothered me for a while.
ABX