Beth Ford, RHIT, CCS, Clinical/Technical Editor
At the meeting of the ICD-9-CM Coordination and Maintenance Committee March 5, 2012, at the headquarters of the Centers for Medicare and Medicaid Services in Baltimore, attendees reviewed the following ICD-10 Medicare severity diagnosis-related group (MS-DRG) topics.
ICD-10 MS-DRG Update
The MS-DRG V29.0 definitions manual update includes changes that reflect the ICD-9-CM MS-DRG V29.0 changes, including:
- New, deleted, and redefined DRGs
- New and deleted diagnosis and procedure changes
- Procedure DRG assignment changes
- Additions and deletions to the complication and comorbidity (CC) exclusion list
- Changes corresponding to the fiscal 2012 ICD-10 code set
- Changes made through testing and public comment review
MS-DRG changes made through public comment review include moving ICD-10-PCS procedure 0DB80ZZ Open excision of small intestine to MS-DRG 329–331 and adding ICD-10-CM code Z23 Encounter for immunization from DRG 794 to DRG 795, under the “only secondary diagnosis list.” Category A41.0 was expanded to fifth character subclassifications for fiscal 2012, allowing new codes A41.01 and A41.02 to be added to the MCC list.
A summary of changes to the definitions manual was provided in text file format for codes V28.0 to V29.0. This document summarizes:
- New, deleted, and redefined DRGs
- New and deleted diagnosis and procedure codes
- Changes in DRG assignments
- Changes in MCC/CC status, HIV status, present-on-admission (POA) exempt list and CC exclusions
- Changes to codes for hospital-acquired conditions (HAC)
The updated MS-DRG V29.0 Definitions Manual is available in text and HTML versions on the CMS website here. The Summary of Changes document will be posted on this website when available.
Translation of HAC to ICD-10 Codes
CMS is translating ICD-9-CM hospital-acquired conditions into ICD-10-CM and ICD-10-PCS codes. The final HAC list translation will be subject to formal rule making; the public is encouraged to review the list of current ICD-10-CM/PCS code translations on the CMS website and submit comments. The HAC translations list is available on the CMS website here.
Locate the HAC translations under the ICD-10 MS-DRG v28 R1 definitions manual (updated October 4, 2011)- HTML Version link in appendix I.
Impact of the Transition to ICD-10 on Medicare Inpatient Hospital Payments
Liz McCullough of 3M reported on the estimated impact on aggregate inpatient prospective payment system (IPPS) MS-DRG payments to hospitals and the distribution of payments across hospitals due to the transition to ICD-10. This presentation was a repeat of a prior presentation from 2009, which at that time received little comment or response. 3M hopes that the public will look again at the impact and make additional comments as implementation approaches.
Two approaches to ICD-10 transition were presented, including the MS-DRG conversion to ICD-10, as well as a mapping of ICD-10 input data to ICD-9-CM, with continuance of the ICD-9-CM version of the MS-DRG Grouper. The latter approach was applied in the interest of payers and entities not ready for the conversion, which are looking at alternatives and mapping implications. 3M reviewed the MS-DRG resources for both systems: general equivalence maps (GEMs) and reimbursement maps, to analyze how well the current MS-DRGs were replicated under ICD-10. MedPAR data comprised a total of 11 million acute care inpatient claims, which were reportedly used to convert coded data to ICD-10. The basis of comparison and analysis and a process overview were provided, along with context-specific translation rules addressing the problem of “one-to-many” ICD-9 to ICD-10 translations. Three groupings were made based on the fiscal 2009 MedPAR data, which compared native ICD-9-CM grouped data to native ICD-10 grouped data and compared that data with the ICD-10 version mapped back to native I-9 using the reimbursement map.
The results indicated a minimal impact on aggregate payments to hospitals (+0.05 percent) and on the distribution of payment across hospital types (-0.01 to +0.18 percent).
Mapping ICD-10 data back to ICD-9-CM and using the ICD-9-CM version of the MS-DRGs was found to have a modest negative impact on hospitals (-0.34 percent). The use of reimbursement maps and of the ICD-9-CM version of the MS-DRGs resulted in 3.66 percent of patients being assigned to different MS-DRGs, with a bias toward lower-paying DRGs. It was noted that this bias existed even though the reimbursement map was tailored specifically for inpatient payment. It was concluded that applying the reimbursement map to the all-patient refined DRGs resulted in a 4.47 percent APR-DRG change.