Net of hospital department charge (6)
I believe the answer is:
entrap
'net' is the definition.
(thesaurus)
'hospital department charge' is the wordplay.
'hospital department' becomes 'ent'.
'charge' becomes 'rap' (I have seen 'Criminal charge ' mean 'rap' so perhaps 'charge' could also mean 'rap').
'ent'+'rap'='ENTRAP'
'of' is the link.
(Other definitions for entrap that I've seen before include "Catch like parent" , "Parent (anag)" , "Deceive -- lead on" , "net" , "Lure into danger" .)