Perhaps you will allow me, on the occasion of the hubbub over the fate of Terri Schiavo, to recommend a couple of books on medical ethics from two thoughtful Christian writers.
First, A Doctor's Casebook in light of the Bible by Paul Tournier. Tournier was a physician from Switzerland who put a lot of thought into holistic ideas of medical care. His faith was not fully orthodox from my point of view (he was a universalist), but his mind was very penetrating about issues of health. It is unfortunate that his works are not very popular in the States. His writing reminds one of CS Lewis, with whom he was friends iirc.
The other is Truthfulness and Tragedy by Stanley Hauerwas. Prof. Hauerwas takes a very sharp look at a number of specific issues, including abortion and the problem of the limits of medical responsibilities. Certainly a more philosophical work than the other, but well worth examination.