I am a GI coder/biller and am unsure if I should always be billing the new moderate sedation codes with the colonoscopies and upper endoscopies. The codes are 99156 (99157 add on) and 99152 (99153 add on). Our practice is brining in CNRA's and I just want to be sure that I'm doing things correctly. It's unclear to me if these codes should only be billed when a CNRA is present or anytime moderate sedation is used. Any information is greatly appreciated!!