Tip: Even if you voluntarily refund improper payments to your MAC, the RAC might still audit the claim. • Blood transfusion codes 36430-36455, which should be billed once per session, despite how many units are transferred. • Untimed codes, excluding modifiers KX and 59. You should bill one unit of these codes per date of service. • IV hydration therapy (formerly code 90760, now 96360). You should report just one unit of this code per patient per date of service. • Bronchoscopy codes 31625-31628, for which you should bill just one unit per date of service (excluding claims with modifier 59). • Once in a lifetime procedures, which should be billed just once in a beneficiary's lifetime. • Pediatric codes that are billed for patients who exceed the age limit defined by the CPT code. • Pegfilgrastim injections (J2505), for which you should only bill one unit per date of service. Connolly Consulting announced that it will be reviewing the areas above for dates of service beginning on Oct. 1, 2007. Tip: If you perform any of the seven listed review areas, you may want to start reviewing those records to ensure that you've billed properly.But keep in mind, "If you start looking at records retrospectively and find any problems, you create additional obligations on yourself to self disclose any wrongdoing," advises Michael F. Schaff, Esq., with Wilentz, Goldman and Spitzer in Woodbridge, N.J. Indeed, the CMS Web site notes that if your self-audit identifies improper payments, you should report the improper payments to your MAC, and remit any necessary refunds. "The RAC will be aware of the adjustment, but the refund does not preclude future review," CMS notes in its RAC FAQs. Analysts advise practices in the other RAC regions to check their contractors'Web sites on a regular basis to determine whether they have posted their audit issues yet.