What happens if they need hospital care while I'm out of the country?

With modern technology, a Power of Attorney can be anywhere in the world and still be able to communicate if one's parent needs medical care.... cellphones, emails, etc.

When my BIL died, one of his son's was extremely difficult to contact because he was mountain climbing in Nepal. If you are going to be somewhere really remote, Ridlenkr, then maybe it would be best for your sister to be the first contact while you are gone. Out of state is probably more reliable than out of the country, depending on where you are going.

I don't think you can legally delegate your authority. How long are you going to be gone?

I recently placed my mother in a nursing home for a couple of weeks respite stay while almost the entire family was away attending a wedding at an island resort. I went over a few possible scenarios with the facility director (I specified comfort care only, and she already has a DNR) and left contact info for the resort, that was the best I could do.
Today many people take their phones with them when they travel and prepay a fee for roaming charges. As others have said, unless you are in a very remote area or will not have a set itinerary contacting you should not be an issue.

Is there an alternate designated on the HCP/Living Will/DNR when you are not available?

This is a good question. My daughter and son-in-law are in the military and have POA over my husband and my-self. We have POA over my Mom 91 in a memory care unit and want to visit daughter and son-in-law in Japan. It should be easy to contact my daughter but find it hard at times. Maybe it is just her I don't know. We have Skype, e-mail and cell phones.

I live overseas and I recommend you go to Japan and visit your daughter. You have several ways to reach you so please go visit your daughter. Anyone trying to reach you will eventually get through. Give them your daughters contact info as well as your own. Have a great trip Give a Hug

Just make sure they know where you are going to be and how to get a hold of you, and your sister. Both of you should carry a med list for what meds your parents are on. You could call once a day to check on things, if that makes you feel better.

I don't think there is any country that doesn't have a fax machine. If you do not want to appoint someone in your place, leave standing orders with the nursing home what you want done in case of...