I will be having a serious operation and I am preparing an Advance Directive for the hospital. Are there any specific directives of the Church for end-of-life issues that I should be aware of?

Yes.  Basically, as Catholics we have a moral obligation to take “ordinary” means to preserve life, but no one is obliged to take “extraordinary” means.  For a more complete answer you can download a pamphlet produced by the Michigan Catholic Conference. This pamphlet contains:

• Guidelines regarding end of life decisions... the Catholic Church’s teaching and direction as a context for these decisions
• Durable Power of Attorney for Healthcare... a document creating a Durable Power of Attorney for Healthcare decisions
• Acceptance by Patient Advocate
• Wallet Identification Card