You may know what types of medical care you want, but what if you cannot tell the doctors? What if you have a stroke, for instance, and you are unconscious when you reach the hospital. How are doctors supposed to know if you want to use life support, if you want to be resuscitated and what other types of care they should provide?
The answer lies in an advance directive. This is a document that you can set up before you need it to make these decisions. There are two main types: An instruction directive and a proxy directive.
This directive lays out your wishes in writing so that doctors can "consult" you even if you cannot speak to them. For instance, perhaps you never want them to resuscitate you if you pass away. You still want them to do everything they can to save your life before that point, but, if you pass away and can only be saved with emergency technology, you just believe it is your time.
You especially need to include any directions that go against what doctors are naturally inclined to do.
This directive does not mention your personal preferences, but instead names someone else to make choices for you, such as a spouse or a child. This can be helpful if you feel like you can't possibly consider all contributing factors and you need someone to make decisions in real time. The potential downside, of course, is that this person needs to be at the hospital. What if you pick your spouse and then you both suffer serious injuries in the same car accident?
As you can see, it is very important to understand all of the options you have when doing estate planning and considering your needs in the future.
Source: State of New Jersey Department of Health, "What is Advance Directive?," accessed May 11, 2018