Attentive hospital required removing third of fingers (7)
I believe the answer is:
heedful
'attentive' is the definition.
(heedful can mean listening or paying attention)
'hospital required removing third of fingers' is the wordplay.
'hospital' becomes 'H' (abbreviation for hospital on maps).
'required' becomes 'needful' (synonyms).
'removing' is a deletion indicator.
'third of fingers' becomes 'n' (3rd letter of 'fingers').
'needful' with 'n' removed is 'eedful'.
'h'+'eedful'='HEEDFUL'
(Other definitions for heedful that I've seen before include "Prudent" , "Paying careful attention" , "Cautious" , "Attentive - circumspect" , "Wary" .)