I think the term "active euthanasia" might apply here. The administration of antibiotics is not considered an "extra-ordinary" measure. Neither is food or water, be it from a tube, or i.v. A person's QOL (quality of life) should not be a consideration for withholding ordinary practices of care that would be available to all persons.
Personally, I have not yet heard that antibiotics were withheld. Are you telling me that the only reason that they withheld antibiotics is because he was aged and had seriously advanced Alzheimer's? If this is true, the reasoning that "justified" this decision (and others like it) has serious implications for everyone. There will be a point when we are all aged, unfit, and useless in other people's eyes (if we are lucky enough to get to 93++). Is our existence and purpose on earth any less meaningful because we don't meet the criteria of "productive" according to our modern society? Why couldn't they just let this poor man die a natural death??
So many abortionists are such idiots about the harvesting of their mentalities on the other end!
Perhaps someday, an elderly caregiver will say to a famous abortionist--Welllllll, greetings SOB, take comfort that my removal of your feeding tube is in honor of my aborted brother. Good night! CLICK.