Hello.

Thanks for your query.

If your grand mother's feeding tube fell off and she is only on intravenous fluids even then there is no problem in her survival as all the nutrients and the required calories to run the body are infused using different kinds of fluids.

It is not necessary that she has to take orally by tube in order to survive.
You see the comatose patients do survive for months just on these fluids.

Hope I have answered your query. I will be available if you have any further queries.
Regards

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