ImproperICD-9-CM code assignment led to incorrect grouping of claims to MS-DRG 857 (postoperative or posttraumatic infections with operating room procedure with complications and comorbidities [CC]), according to Recovery Auditors. CMS released the findings in the July 2014 Medicare Quarterly Provider Compliance Newsletter.
CMS provided two examples of incorrect coding and MS-DRG assignment.
In the first, a patient underwent a right total knee replacement recently and was admitted with an infected knee hematoma. The coder assigned ICD-9-CM code 998.59 (other operative infection) as the principal diagnosis and 998.12 (hemorrhage or hematoma complicating a procedure) as the secondary diagnosis. The case grouped to MS-DRG 857.
However, the coder should have assigned ICD-9-CM code 996.66 (infection and inflammatory reaction due to internal prosthetic device implant and graft) because the infection was due to the device. In addition, the secondary diagnosis code should have been 997.77 (other complication due to internal joint prosthesis), according to the Recovery Auditor. The case should have grouped to MS-DRG 487 (knee procedures with principal diagnosis of infection without CC/MCC).
The second case involved a patient admitted for evaluation and therapy of a presumed pacemaker pocket infection. The coder assigned ICD-9-CM code 998.59 (other postoperative infection) as the principal diagnosis. The coder should have reported 996.61 (infection and inflammatory reaction due to cardiac device, implant, and graft) as the principal diagnosis, according to the Recovery Auditor.
The change in principal diagnosis changes the MS-DRG from 857 to 261 (cardiac pacemaker revision except device replacement with CC).