Obviously they couldn't keep them alive but they must have noticed that people in this status still breath and the blood circulation still work. Where they left to die? Did they do some sort of euthanasia? Did they think that they were possesed by some evil spirit?
There's some more concerns that make it difficult. More can be said on the matter of comatose care in the Medieval Period, so if anyone with the right knowledge would like to contribute, please don't hesitate to do so! More posts are always welcome on this sub. For the meantime, OP, these previous posts also cover comas and a similar relevant case: