I have a provider who billed for 36581( replacement ,complete, of a tunneled centarally inserted venous catheter, without subcutaneous port or pump, through the same venous access). However, the documentation shows that what he actually did was convert a non-tunneled venous access devise to a tunneled venous access device through the same venous access site. I believe that, due to the code description, that this was billed incorrectley. I believe that this should have been billed as a placement of a tunneled venous access device (36558). Please advise.