I think you will be lucky to find anything. Though on saying that for the two injured WW1 soldiers I've researched: for the first I bought a copy of his pension record which contained a few words describing his injuries; For the second all I, or rather someone else, found was one page in a local archive that mentioned him being in a particular hospital in France with 'Trench Fever Mild'.
Having also researched a WW1 Nurse, in my experience there's not much if anything regarding WW1 hospitals left.