Oh what an awful situation. That's a terrible weight loss. But if they can't find any reason for it then, yes he will lose weight if he doesn't eat - and become malnourished.
I spent 4 months in hospital, unable to eat due to a medical issue - and the weight loss was huge, so I'm not surprised he's lost a lot of weight if he's not eating.
If you think you can manage at home, then I think you should consider it. But you would need some back up. He must be very frail and under-nourished.
It might also be worth asking if he can have those supplementary drinks - I had one called FORTIJUCE, it is calorie-dense and has essential nutrients. It's only about 200 - 300 ml so not a massive amount to drink. The NHS give them to patients who need building-up or have problems with eating.
But with his mobility problems- and the pressure sores, which can be dangerous, you really will need home visits from nurses. It's an awful lot to take on yourself.
Can you talk to your / his GP, or his consultant about the possibility of bringing him home - but most definitely on the proviso that his care is overseen by a nurse who should be checking on the pressure sores regularly. You need to explore this with the medical profession.
It's awful being a carer - there is so little real practical help available, I sympathise. I hope you manage to sort something out.
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