The 1928 BCP gives a standard order for administering the Blessed Sacrament to the sick, basically just an abridged form of the full service: Collect, Epistle, Gospel, and then everything after "Ye who do truly." There's even a minimized version available for people whose time is very short indeed. After the order and the rubrics, it says this: How much of the order is the priest supposed to use when the sick person can't actually eat and drink? Does he need a relative or some second person available to commune, or does he only say certain sections, or does he not say any of it in this circumstance?
My view is that in all probability, in the case of someone who can't actually eat and drink, the chances are that the appropriate sacramental action would be some form of anointing or unction, rather than a communion of the sick.
I am but a lay person, but that would be my understanding and expectation. My opinion and a ham sandwich together is worth the ham sandwich.
Yes, Botolph has given the usual prescription for the case. In the 1928 American BCP the pertinent sections of material are found on pages 308-320. This is probably the most adaptable portion of the book. The rubrics repeatedly allow the minister to pick and choose from the suggestions on offer. You'll notice that some of the material assumes the sick can participate. If that is not the case there are some passive forms as well. Anointing is optional and I know of a few low church bishops who never bless oil to distribute to the clergy. I suspect these services were intended for the chronically or terminally ill. I use them quite liberally and generally always have a bottle of oil in my travel kit. In fact, I am scheduled to anoint a cancer patient tomorrow.