CMS Releases 2021 Final Outpatient Prospective Payment System/Ambulatory Surgical Center Rule On December 2, CMS finalized policy changes for the Outpatient Prospective Payment System (OPPS) and Ambulatory Surgical Center (ASC) final rules. In this final rule, CMS will begin eliminating the inpatient only (IPO) list of 1,700 procedures for which Medicare will only pay when...