Hospitals may feel like they’ve gone to crazy town when they find procedures on the inpatient-only list (IPO) that were dropped years ago, before CMS began the elimination of the IPO list and then changed its mind in the 2022 outpatient prospective payment system regulation finalized Nov. 16.^[1] But it isn’t the hospitals; the IPO list uses the CPT short descriptors, and it may take extra effort to figure out which procedures are being performed and ensure they get the right code from surgeons, an expert says. A lot rides on this because Medicare only pays for procedures on the IPO list when they’re performed on inpatients.

A classic case is total hip arthroplasty (THA). It was moved off the IPO list in 2020, before CMS started phasing out the IPO list, a move it has reversed, according to Ronald Hirsch, M.D., vice president of R1 RCM, who spoke at a Dec. 2 webinar sponsored by RACmonitor.com.^[2] If hospitals look only at Addendum E, the IPO list in the OPPS rule, it seems like THA is still there, he said. For the sake of compliance and revenue, hospitals have to do a more comprehensive analysis, looking at Addendum B, the all-surgeries list, and their coding book, to nail down what’s truly on the IPO list and what’s in the realm of the two-midnight rule, he said. It sounds counterintuitive to say looking at the inpatient-only list isn’t adequate, but Hirsch said that’s how it’s playing out.