From 3M Health Information Systems
ICD-10 MS-DRG shifts, Part 4 – Next 5 DRGs
Last time, we looked at the top five “shifty” DRGs (MS-DRGs in ICD-9 which, when translated to ICD-10 and re-grouped with the proposed ICD-10 MS-DRGv30 grouper, got different MS-DRGs). Now we continue with the next five.
6. MS-DRG 191, Chronic obstructive pulmonary disease with CC.
Negative, about 18 cents per $100 of DRG 191 reimbursement. 82% of the change is due to ICD-10 not differentiating sub-types of COPD the way ICD-9 does. ICD-9 has unique codes for an acute exacerbation of obstructive chronic bronchitis (491.21, 491.22) and unspecified acute exacerbation of chronic obstructive asthma (493.21, 493.22). All are on the CC list in ICD-9 MS-DRGs, and when two such codes are on the record and one is listed as principal diagnosis, the MS-DRG assigned is DRG 191 Chronic obstructive pulmonary disease with CC.
For a diagnosis of COPD with acute exacerbation, there is just one code in ICD-10, J44.1 Chronic obstructive pulmonary disease with (acute) exacerbation, which includes patients with the diagnoses of chronic obstructive bronchitis, chronic obstructive asthma, as well as chronic obstructive pulmonary disease. Therefore, an ICD-10 coded record for a patient with multiple COPD sub-types documented will still only have one code on the record, and if listed as the principal diagnosis will be assigned to DRG 192 Chronic obstructive pulmonary disease without CC/MCC.
In approximately half of all hospital admissions for COPD exacerbation, the specific cause is pneumonia, and the diagnosis is more accurately coded using ICD-10 code J44.0 Chronic obstructive pulmonary disease with acute lower respiratory infection, instead of J44.1. If documented as the cause of the COPD exacerbation, pneumonia can be coded in addition to J44.0. Most viral and bacterial pneumonias (see codes in categories J12-J18) are on the ICD-10 MCC list.
7. MS-DRG 11, Tracheostomy for face, mouth and neck diagnoses with MCC.
Positive, about $2.60 cents per $100 of DRG 11 reimbursement. We haven’t yet analyzed all the positive changes. Take the money.
8. MS-DRG 974, HIV with major related condition and MCC
Negative, about 46 cents per $100 of DRG 974 reimbursement. In addition to the reasons for losing an MCC we’ve already discussed, about 57% of the DRG 974 shifts are due to an unavoidable difference in the way ICD-10 codes for sepsis.
A correctly coded ICD-9 record requires two codes to fully specify sepsis due to an organism: one code for the septicemia organism and a second code for the clinical condition of sepsis (e.g., 038.41 Septicemia due to hemophilus influenzae and 995.91 Sepsis). Both codes are on the MCC list in ICD-9 MS-DRGs, but 995.91 is excluded as an MCC when HIV is listed as principal diagnosis. However, since 038.9 is not excluded, a record with HIV as principal diagnosis and both 038.9 and 995.91 is assigned to DRG 974 HIV with major related condition with MCC.
Sepsis codes in ICD-10 (category A41 et al) specify both the septicemia organism and the clinical condition of sepsis in one code. Therefore, a correctly coded ICD-10 record requires only one sepsis code (A41.3 Sepsis due to Hemophilus influenzae). In ICD-10 MS-DRGs, when HIV is listed as principal diagnosis, A41.3 as a secondary diagnosis is excluded as an MCC, because its closest matching ICD-9 translation, 995.91, is likewise excluded in ICD-9 MS-DRGs.
9. MS-DRG 552, Medical back problems with MCC.
Positive, about 68 cents per $100 of DRG 552 reimbursement. Despite all the ways a DRG could lose an MCC, DRG 552 comes out positive for an as-yet-unanalyzed reason.
10. MS-DRG 292, Heart failure and shock with CC.
Negative, about 26 cents per $100 of DRG 292 reimbursement. Even at rank 10, this is an important one because DRG 292 occurs about 22 thousand times per million Medicare cases. Shifts occur for 10 different reasons, mostly having to do with the loss of the CC, but one accounts for 67% of the shift and 80% of the reimbursement reduction: malignant hypertension. It is classified with its own unique code in ICD-9 (401.0). It and a related code (402.00 Malignant hypertensive heart disease without heart failure) are on the list of CCs in ICD-9 MS-DRGs. ICD-10 does not classify the concept of malignant hypertension as a distinct clinical condition, so there are no comparable ICD-10 codes specifying malignant hypertension on the CC list in ICD-10 MS-DRGs.
But all is not lost. Malignant hypertension is considered by many to be an outmoded term for a condition called “hypertensive urgency” or a “hypertensive crisis/emergency.” It manifests as a severe, sudden rise in blood pressure that can cause a cerebral infarction (I63.0-I63.5 are MCCs) or manifest with acute organ damage such as pulmonary edema (J81.0 Acute pulmonary edema is MCC), or kidney failure (N17.9 Acute kidney failure, unspecified is CC). Ensure that all related manifestations of a hypertensive crisis are fully documented and coded.
Ron Mills is a Software Architect for the Clinical & Economic Research department of 3M Health Information Systems.