I am not Catholic, but a recent conversation elsewhere has brought back to my mind the fact that the USCCB has implied that a means for preserving life may be "disproportionate" if it imposes "excessive expense."
Some people attempt to use this loophole to justify the murder (yep, I call it that) of helpless people like Terri Schiavo by depriving them of mere nutrition and hydration. The claim is that it is "excessively expensive" to "keep alive" someone like Terri.
My own strong preference would be for understanding ordinary and extraordinary care in biological terms, in terms of whether the body is actively dying, in terms of what everyone needs, and so forth, rather than in terms of expense. But it may be expected that the ordinary/extraordinary distinction will track the "very expensive/not-so-expensive" distinction, on the assumption that extraordinary care involves expensive technology.
People--especially Catholics--who want to excuse depriving the Terris of the world of mere food and water via a perceived "expense" loophole in the Church's teaching need to be brought up short by the following consideration: It is not the "artificial" nature of the nutrition and hydration that are the chief cause of expense for such helpless people. It is the fact that they live, are helpless, and need ordinary care: things like diaper changing, being turned in the bed, bathing, etc. This sort of care is what is most expensive, especially if the people closest to the helpless adult are unable because of strength considerations or unwilling to do that work.
Thought experiment: Suppose that a helpless, severely disabled adult like Terri were magically made able to survive without food and water but still needed day-to-day bodily care. Would the "expense" of her life be drastically decreased? I say that it would not. It's not the cost of the insertion of the PEG tube nor the cans of adult "formula" that are the heaviest expense. It's the fact that the person is alive and needs to be cared for as a baby would.
But so what? Question: Do we consider it "medical care" to bathe, clothe, change, and otherwise care for a baby? Do we consider such normal forms of care to be "extraordinary" or "disproportionate"?
The care of helpless adults is deemed "medical" because their being helpless means that something is wrong with them and also, practically, because it is so much more work to take care of them and is best done (though not necessarily done) by those with special training and a good deal of physical strength.
Once we realize that it is paradigmatically ordinary care that is so expensive for these people--"expensive," at least, in terms of time and effort, even if able to be undertaken by loving family--that it is simply their existence as helpless people that is expensive, I think we will realize that it is the merest sophistry to talk as if it is their "artificial" feeding that is "extraordinary" or "excessively expensive" and focus on that as an excuse for getting rid of them. One irony here is that tube feeding actually decreases the difficulty (and hence, the expense) of caring for a helpless person. It enables that person to get the necessary nutrition and hydration fairly easily, where spoon feeding would be much less efficient, enormously more time-consuming, probably would not provide adequate nutrition to an adult, and takes more skill to do safely.
The issue, then, is not that tube feeding is specially expensive, hence extraordinary, hence conveniently optional. The issue is that people who can't care for themselves need a lot of care.
But we knew that already. And if someone thinks that morally excuses dehydrating them to bring their expensive lives to a quicker end, he has a major problem.
(Warning to liberal trolls: I have a delete key, and I'm not afraid to use it.)