Plot escape, causing uproar (6)
I believe the answer is:
'uproar' is the definition.
(I've seen this in another clue)
'plot escape' is the wordplay.
'plot' becomes 'bed' (a plot of land).
'escape' becomes 'lam' (lam is a kind of escape).
'causing' is the link.
(Other definitions for bedlam that I've seen before include "Blamed for confused uproar" , "Noisy confused state" , "Place of uproar or madness" , "Very noisy confused place" , "Blamed for 9 across? (8)" .)