A Urinary catheter is inserted for a variety of reasons  It depends on the reason as to how removal may affect what issues may arise. 

There is the possibility of urinary tract infection with catheter removal and this why catheter removal should be a sterile procedure. 

Sometimes urinary retention will occur and reinsertion may be necessary. Many patients have urinary retention right after surgery. 

The combination of anaesthesia and intravenous (IV) fluid may result in a full bladder with impaired nerve function, causing urinary retention. Normal bladder nerve function usually returns once the anesthesia wears off.

post cathether removal issues