By Ann Barta, MSA, RHIA, CDIP
The implications of ICD-10-CM/PCS for healthcare reimbursement is a topic at the top of everyone’s mind in the healthcare industry these days. As healthcare organizations continue to prepare for the transition to ICD-10-CM/PCS on October 1, 2015, an essential and important element of a successful transition is the understanding of the implications that this transition will have on reimbursement for healthcare organizations.
United Audit Systems, Inc. (UASI), a vendor specializing in coding and revenue cycle solutions, has been performing ICD-10-CM/PCS documentation gap analysis projects for the past three years. In addition to assisting healthcare organizations with identifying and understanding specific gaps in their clinical documentation, these projects also included the performance of a financial simulation comparing the ICD-9-CM MS-DRG assignment to the ICD-10-CM/PCS MS-DRG assignment. Overall, the financial simulation findings for various healthcare organizations have revealed only modest changes in the organization’s case mix index (CMI), holding consistent with the Centers for Medicare and Medicaid Services’ goal of a revenue neutral transition to ICD-10-CM/PCS.
This article will discuss some potential MS-DRG changes related to the organization and structure of ICD-10-CM/PCS, as well as the native MS-DRG grouper logic.
Analysis for Supraventricular Tachycardia
The code for supraventricular tachycardia in ICD-9-CM is 427.89, Other specified cardiac arrhythmias. The code 427.89 is listed neither as a major complication or comorbidity (MCC) nor as a complication or comorbidity (CC) when assigned as a secondary diagnosis in ICD-9-CM. In comparison, ICD-10-CM has a specific code for supraventricular tachycardia, I47.1, which is listed as a CC.
This change has the potential of resulting in a higher MS-DRG being assigned in ICD-10 if supraventricular tachycardia is the only secondary diagnosis qualifying as either a MCC or CC. The following is an example scenario that illustrates the resulting MS-DRG change.
A patient is admitted to the hospital with a principal diagnosis of congestive heart failure and a secondary diagnosis of supraventricular tachycardia. In ICD-9-CM this case would be grouped to MS-DRG 293 (RW 0.6762). In ICD-10-CM/PCS this case would be grouped to MS-DRG 292 (RW 0.9824).
Analysis for Urinary Calculus with Hydronephrosis
The diagnosis of a urinary calculus with hydronephrosis results in two codes being assigned in ICD-9-CM. One code is assigned for the calculus and another code is assigned for the hydronephrosis. Although the urinary calculus code is a non-CC code, the hydronephrosis code is a CC code. ICD-10-CM has new combination codes for urinary calculus and hydronephrosis. These new combination codes often result in the loss of a secondary CC code for the hydronephrosis. The following are two example scenarios illustrating the loss of the secondary CC code.
In the first scenario, a patient is admitted with right ureteral calculus with hydronephrosis and undergoes a transurethral removal of the ureteral calculus with an insertion of a ureteral stent. In ICD-9-CM the MS-DRG assigned to this case is 669 (RW 1.2662). In ICD-10-CM/PCS the MS-DRG assigned is 670 (RW 0.8957). The reason for the lower MS-DRG assignment is the result of the loss of the CC for the secondary diagnosis of hydronephrosis.
For the second scenario, a patient is admitted with a right ureteral calculus with hydronephrosis and undergoes extracorporeal shock wave lithotripsy. In ICD-9-CM the MS-DRG assignment for this case is 691 (RW 1.6238). In ICD-10-CM/PCS the MS-DRG assignment is 692 (RW 1.1286). Again, the reason for the lower MS-DRG assignment is the result of the loss of the CC for the secondary diagnosis of hydronephrosis.
Analysis for Neutropenic Fever with Leukemia
In ICD-9-CM, if the reason for an admission is neutropenic fever and the patient has leukemia, the principal diagnosis is the appropriate ICD-9-CM diagnosis code for the type of leukemia. The leukemia code is the principal diagnosis code as a result of an Excludes note located under category 288, Diseases of the white blood cells, stating “Excludes: leukemia (204.0 – 208.9).” No such Excludes note appears in the ICD-10-CM Tabular allowing the code for neutropenic fever to be assigned as the principal diagnosis for the same case scenario.
The following is an example scenario that illustrates the resulting MS-DRG change. A patient with acute lymphoblastic leukemia is admitted with neutropenic fever. In ICD-9-CM a code for the type of leukemia would be assigned as the principal diagnosis resulting in the assignment of MS-DRG 836 (RW 1.1693).
In comparison, in ICD-10-CM a code for the neutropenic fever would be assigned as the principal diagnosis with a secondary diagnosis code being assigned for the type of leukemia, resulting in the assignment of MS-DRG 809 (RW 1.2037). Note that the ICD-10-CM code for leukemia is a secondary CC code.
In ICD-9-CM, the above case scenario with a CC secondary diagnosis code results in the assignment of MS-DRG 835 (RW 2.1042) and a MCC secondary diagnosis code results in the assignment of MS-DRG 834 (RW 5.2735). In comparison, the above case scenario coded in ICD-10-CM with a secondary MCC diagnosis code results in the assignment of MS-DRG 808 (RW 2.226).
Analysis of Mastectomy with Excision of Regional Lymph Nodes
Code 85.43, Unilateral extended simple mastectomy, is an ICD-9-CM combination code assigned for the performance of a total simple mastectomy with the removal of regional lymph nodes. ICD-10-PCS requires assignment of two codes for this same procedure, a code for the total mastectomy and a code for the removal of the regional lymph nodes. The following example illustrates the resulting MS-DRG change for this case scenario.
A patient with carcinoma of the right breast undergoes a total right mastectomy with removal of regional lymph nodes. The MS-DRG assignment for this case is 583 (RW 1.0932) in ICD-9-CM and MS-DRG 581 (RW 1.1338) in ICD-10-CM/PCS.
Atrial Fibrillation Coding
ICD-9-CM has only one code for classifying atrial fibrillation, 427.31, Atrial fibrillation. The code 427.31 is neither a MCC or CC when assigned as a secondary diagnosis in ICD-9-CM. In comparison, the ICD-10-CM category for atrial fibrillation has been expanded to include the following specific types of atrial fibrillation:
- I48.0, Paroxysmal atrial fibrillation
- I48.1, Persistent atrial fibrillation
- I48.2, Chronic atrial fibrillation
- I48.91, Unspecified atrial fibrillation
Code I48.1, Persistent atrial fibrillation, qualifies as a CC code and has the potential of resulting in the assignment of a higher weight MS-DRG if persistent atrial fibrillation is the only secondary diagnosis qualifying as either a MCC or CC. The following is an example scenario that illustrates the resulting MS-DRG change.
A patient is admitted for treatment of acute on chronic diastolic congestive heart failure. Review of documentation indicates that the patient is also being treated for a secondary diagnosis of persistent atrial fibrillation. The MS-DRG assignment for this case scenario is 293 (RW 0.6762) in ICD-9-CM and 292 (RW 0.9824) in ICD-10-CM/PCS.
Analysis for Rib Fractures
ICD-9-CM has the following codes for classification of a rib fracture:
- 807.00, Rib fracture, unspecified
- 807.01, Rib fracture, one
- 807.02, Rib fracture, two
- 807.03, Rib fracture, three
- 807.04, Rib fracture, four
- 807.05, Rib fracture, five
- 807.06, Rib fracture, six
- 807.07, Rib fracture, seven
- 807.08, Rib fracture, eight
- 807.09, Multiple rib fracture, unspecified
ICD-10-CM has only two subcategories for the classification of rib fractures:
- S22.3, Fracture of one rib
- S22.4, Fracture of multiple ribs
Both of these subcategories are further expanded by the laterality of the rib fracture(s) and the encounter episode.
Despite the difference in the coding specificity between ICD-9-CM and ICD-10-CM for fractured rib(s), if the reason for the admission is for treatment of fractures, the MS-DRG remains the same for ICD-10-CM/PCS as for ICD-9-CM—except in the case when the patient’s principal diagnosis is for the fracture of two ribs. The principal diagnosis of a fracture of two ribs results in the assignment of MS-DRG 206 (RW 0.7942) in ICD-9-CM and MS-DRG 185 (RW 0.6628) in ICD-10-CM/PCS.
Ann Barta (firstname.lastname@example.org) is a senior HIM consultant at UASI.
"ICD-10 Gap Analysis Points to Revenue Neutral Transition"
Journal of AHIMA