Green’s Dictionary of Slang

one who is ruined, on the verge of death or collapse.

1838		Session Papers of the Central Criminal Court in DSUE (1984).
1867		Leeds Times 23 Feb. 6/3: A man to be a ’bus driver must ave hiron narves [...] and his knowledge-box must be screwed right atween his shoulders, or he’s a dunner.
1930		E. Raymond Jesting Army in DSUE (1984).