It looks like this thread is going to end up being locked anyway, but I will add my 0.02 worth. First of all, I am not really sure what you are talking about. Are you asking if we as nurses need to be more aware of the needs of people who don't speak English? If so, no, we don't, We have to be aware of many differences in culture, dialects. personalities, reactions to illnesses, anger, psych problems, etc. So language is just one more problem we deal with on a daily basis.
I have never heard the term "Sustainable English" before and on the surface it sounds like learning enough English to get by, sort of like learning a little conversational Spanish, French, etc before taking a trip to another country.
Now for the non politically correct portion of my comment. If someone comes to this country to live, work, have their children in school, shop in the stores, vote in elections, drive on the roads....then they need to learn the language of the country they are living in. In this case it is English. I would never go to another country and expect to have translators in schools, hospitals, be able to vote in their elections, and have instructions for everything from surgical consents to cooking rice a roni in my native language! It would never be done or tolerated!
Still, I don't know what you are asking, but I feel better for venting!