Why Is CPR Considered Futile For Seniors?

CPR (Cardio-Pulmonary Resuscitation) was developed in 1959 primarily for middle-aged people having a cardiac arrest:  while the chest is thumped (breaking seniors’ ribs), a tube is put down the throat into the lungs, and the heart may be shocked.
A futile or non-beneficial procedure is defined as such when it will not help someone achieve their goals; or, when fewer than five people out of a hundred would survive. 
Since the goal for most seniors is a peaceful and dignified death; and since CPR is a harsh procedure incompatible with a peaceful end; and since the chance of success for seniors is between zero and 17%, averaging 5%, with the few survivors usually worse off; then, CPR is futile and inappropriate for seniors.
Why doesn’t it work?  Physiologically, seniors do not have the reserve to deal with such a failure of their organs:  they usually have multiple chronic problems and when the heart stops, it’s usually a sign that the body is worn out.  CPR (especially in hospice) offers only false hope when we should be helping families prepare for the final stage in life.
Although the signs of approaching death usually allow a doctor an opportunity to write AND/DNR (Allow Natural Death / Do Not attempt Resuscitation), prior to that point many patients can have a crisis, resulting in unwanted CPR.
So, to avoid leaving family with the memory of such a traumatic event, seniors need to tell their families and physicians they want an order for AND/DNR – and put it in their Advance Directive.