Husband finding hospital bed uncomfortable

He's had a hospital bed delivered. He's is on his third mattress, as he can't get comfortable. Today a plug in mattress was delivered and fitted. It's too hard for him. I've suggested we contact the district nurses again tomorrow as I don't know what to do. I feel so helpless. I do my best but I can't get him comfortable. He is fairly mobile. The lack of sleep is doing him no good at all.
 

He's not well. He has terminal primary liver, spinal and bone marrow cancer. It was advanced stage that had spread last January. He was given 4-6 months without treatment, maybe a year with. I can feel lumps on his spine where he's getting pain. He gets scan results on Thursday with a what's next to do. I'm so anxious, he's definitely and understably anxious.I just wish I could help him get some comfort at night, somewhere he could lie easily