I’m not so sure. My FIL had advanced directives...no feeding tube, no ventilator. He contracted MRSA pneumonia after a surgery to repair his hip (he had fallen.) He was 93 years old, we had his wishes in writing along with a health care surrogacy document and almost everyday the physicians pushed for a feeding tube and ventilator. He had been transferred to a “specialty hospital” for folks with chronic problems (I believe you could substitue the word “terminal” conditions.) He was the only patient in the hospital that was not on a ventilator and did not have a feeding tube. One woman, whose husband was in the room across the hall, told us how she had been pressured into the ventilator and feeding tube after her husband suffered a massive stroke. And now, many months later, he was still in the same state, physicaly with no improvement and no response, but alive because of the machines.
Years ago I attended a seminar with Dr. Koop and Francis Schaeffer. I can distinctly remember Dr. Koop commenting on the advances in modern medicine and not starting extraordinary measures when someone is deemed terminal(I believe the discussion centered around Karen Ann Quinlan.)
My grandmother was felled by a stoke many years ago. My grandfather kept her at home with the services of nurses. She had no movement except her eyes and no special equipment to speak of. She lived 7 more years. We wouldn’t have it any other way. Also, he was wheelchair bound; but drove a car.
I believe everyone has a quality of life. It is how it is perceived.