Been there, done that for many months a while back.
It will be very frustrating for him, and will probably make him angry and other side effects.
If its possible to convey to him that it WILL get better, and support to that effect works wonders on a drugged up sedated mind usually.
Times passes so slowly when you are that side of the bed, but with the time passing, health improves.
My neighbour spent several months in Burwood this year after a fall from a horse and she's doing ok now, its taken a while but she's up and about ok.
Pass on my best wishes, and convey from my experiences that it may seem a real bastard now, but it will get better.
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