Don’t forget that if a dying patient is uncomfortable, it is perfectly acceptable to use whatever doses of morphine, sedatives, etc. it requires to keep him or her comfortable, even if you know it is going to hasten the patient’s death. As long as the intention is to relieve comfort and not to kill the patient, this is perfectly legal, considered by most to be ethical, and is absolutely standard of care in this situation.
Simply put, there is no reason for a patient to die in discomfort. The current ethical climate does not allow for active euthanasia, but it does allow for, and IMO requires, proper comfort care.
Unfortunately this option is foreclosed by events. Brain scans of Schiavo were taken by court order in 1996 (today’s Los Angeles Times, click on the drawing of the brain at right. Requires registration). Neurologists at the time concluded that her cerebral cortex which registers sensations was gone so there wouldn’t be any sensation of pain. Therefore there wouldn’t seem to be any medical reason to prescribe any palliative sedatives. And so giving her such drugs would clearly be for the purpose of euthanasia and Uncle Sam, in the person of the Department of Justice and maybe Congress and the Brothers Bush, would be on your ass.
The problem that I see with the argument that starvation is cruel is that almost any form of death requires that cells be killed by lack of nourishment, water, or oxygen. In a heart attack such as arrest, the heart stops pumping blood, the brain cells don’t get oxygen and suffocate. In pneumonia, which can be brought on for a terminal patient by the inactivity resulting from sedation, the same thing. Lungs fill and reduce the oxygen supply which suffocates brain cells.
I don’t know how toxins kill, but I suspect that it isn’t any more pleasant for a functioning brain than any other method.
None of this seems applicable to the Schiavo case because the evidence is clear that to the best of our knowledge she has no part of her brain left to produce sensations.