Exhausted American editor gets out of bed (4,2)
I believe the answer is:
used up
'exhausted' is the definition.
('use up' can be a synonym of 'exhaust')
'american editor gets out of bed' is the wordplay.
'american' becomes 'US' (United States).
'editor' becomes 'ed' (abbreviation).
'gets' is a charade indicator (letters next to each other).
'out of bed' becomes 'up' (synonyms).
'us'+'ed'+'up'='USED-UP'
(Other definitions for used up that I've seen before include "Spent" , "Exhausted the supply" , "Consumed completely" , "Consumed, finished" .)