I think the idea was that the hosts would have to supply meals and drinks and keep them company but that would be it pretty much. They wouldn't need any special experience but they would get some training and have a helpline to call if they had any problems.
I don't think it was actually that bad an idea but the hospital who was going to trial it has now backed out:
http://www.bbc.co.uk/news/uk-england-essex-41763730