HIMagine That! Coding Variance from ICD-9 to ICD-10

August 12th, 2013 / By Sue Belley, RHIA, Donna Smith, RHIA

Donna: Sue, I have been reviewing data files with ICD-9 codes translated to ICD-10 to determine if there are DRG changes between the two coding systems.

Sue: Well, Donna, what have you found?

Donna: As you would suspect, there are some variances from the MS-DRG assigned using ICD-9 codes to the MS-DRG assigned using the ICD-10 codes. But that is not the most interesting finding in my review. The issues I have come across are some strange pairings of ICD-9 codes that do not translate well into ICD-10.

Sue: I have heard that there are some variances in a small number of cases. I think one of the most common is when there is an anemia caused by a malignancy. This causes the MS-DRG to change from the anemia MS-DRG to the malignancy MS-DRG. Almost everyone has heard of this change, though, so describe what other things you are finding.

Donna: In some cases there are strange combinations of ICD-9 codes that I can’t use to recreate the patient scenario, and the computer cannot translate accurately. Let me describe one of the weirdest combinations, which I have seen several times. A patient is admitted with a fractured hip, which is treated with an open reduction and internal fixation.

Sue: Nothing odd about that!

Donna: Let me finish – the patient also has two additional surgical procedures listed, a hip revision and a total hip replacement. There are no additional diagnostic codes indicative of a complication so I am not sure how to explain this.

Sue: It could be that the patient has broken both hips and one is repaired by ORIF while the other is repaired with a total hip replacement. The two different fractures could be handled by the laterality available in ICD-10.

Donna: But then why add a hip revision procedure code? Also, since the translation is not clear to the computer, the DRG changes in this case from a bilateral joint replacement to a revision of the hip replacement.

Sue: Maybe the patient came in with a fractured hip which was repaired and then had a complication which was not coded. That would account for at least two of the surgeries.

Donna: All I know is that I don’t think this should be counted as a true MS-DRG change from ICD-9 to ICD-10. I have seen other cases identified as changes when codes are omitted, causing the translation to be less than accurate.

Sue: Do you mean cases where multiple codes are needed in ICD-9 to accurately reflect the complete surgical procedure such as in a PTCA?

Donna: Exactly! Omitting one of the necessary codes causes an incorrect translation. Again, any associated DRG changes should not be blamed on ICD-10.

Sue: I do think in the end the only way to accurately identify a true MS-DRG change is to code the case in ICD-9 using the documentation present and then code the case in ICD-10 using the documentation in the chart.

Donna: I agree – a translation is only an estimate of the MS-DRG variance and can be hampered by a variety of issues, one of which is inaccurate or incomplete ICD-9 coding.

Sue Belley is a Project Manager with the Consulting Services business of 3M Health Information Systems.

Donna Smith is a Project Manager and Senior Consultant with the Consulting Services business of 3M Health Information Systems.