I'm stuck on a few procedures. On 11-6-09 we performed a cath removal 36589 as well as dialysis 90935- both of these were paid. on 11-09 we then died a tunnel cath placement 36561 and dialysis 90935 which are both denying for the global period of 36589 on the 6th. Any idea which modifier I need to use for the 36561 and the 90935? We aso had 90935 on the 7th and 8th which are being denied. I know with a modifier we can at least get the 36561 paid! Any suggestions? Thanks!