“Life is a gift of God, and on the other hand death is unavoidable; it is necessary, therefore, that we, without in any way hastening the hour of death, should be able to accept it with full responsibility and dignity. It is true that death marks the end of our earthly existence, but at the same time it opens the door to immortal life. Therefore, all must prepare themselves for this event in the light of human values, and Christians even more so in the light of faith. As for those who work in the medical profession, they ought to neglect no means of making all their skill available to the sick and dying; but they should also remember how much more necessary it is to provide them with the comfort of boundless kindness and heartfelt charity. Such service to people is also service to Christ the Lord, who said, ‘As you did it to one of the least of these my brethren, you did it to me.’”
—Congregation for the Doctrine of the Faith, Iura et bona, Declaration on Euthanasia (1980), conclusion.

Talking about death with those we love can be something we tend to avoid, nevertheless it is probably the most important conversation we can have. These decisions are difficult and sometimes we need help in applying the general principles about end-of-life medical care to individual cases. Here are a few resources:

The National Catholic Bioethics Center has an emergency consultation number (Monday through Friday, 8 a.m. to 4 p.m. EST): 215-877-2660.

Articles and websites:

Undertaking Death - Catholic Guidelines For End of Life Decisions - Catholics United for the Faith 

A Catholic Guide to End-of-Life Decisions - National Catholic Bioethics Center

Human Life & Dignity - End of Life - USCCB

End of Life Decisions - EWTN

Embracing Our Dying - Catholic End of Life Decisions - California Catholic Conference