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Using ICD-10-AM, ACHI, ACS
Casemix and Diagnosis Related Group (DRG) Allocation
Provided below are the six known scenarios that group to error DRG 901Z Extensive O.R Procedure Unrelated to Principal Diagnosis. The six scenarios have either been fixed or are under investigation.
If you find any error DRG 901Z cases that may reflect pathway errors in the grouper logic, please email us at coding_helpdesk@moh.govt.nz
Mary-Ellen or Tracy will then collaborate with Data Management Services (DMS), the New Zealand Costweight Group, the Australian Institute of Health and Welfare (AIHW) and the National Centre for Classification in Health (NCCH) to investigate these errors and formulate the appropriate requests to have them fixed.
Coders are reminded that it is unacceptable to manipulate the Australian Coding Standards (ACS) when trying to problem-solve an error DRG. Consultation with the Ministry of Health is vitally important to maintain the integrity, consistency and accuracy of the data collection. Error DRGs can be appropriately managed only when there is transparent visibility of what code assignments cause the error in the first instance.
Note:
The DRG code is calculated by the Ministry of Health. It is not reported to the National Minimum Data Set (NMDS) by hospitals. The current DRG grouper is AR-DRG version 5.0, which uses up to 30 diagnoses and up to 30 procedures in its calculations. External cause codes are not used by the grouper. It is recommended that hospitals prioritise diagnoses and procedure codes within current ICD-10-AM Sixth Edition standards and guidelines in order to present the grouper with the most severe diagnoses and procedures.
With the introduction of ICD-10-AM Sixth Edition from 1 July 2008, events coded in this edition will be back-mapped to ICD-10-AM Third Edition and then grouped into AR-DRG 5.0 with New Zealand costs applied (WIESNZ08).
For further information on DRGs and Casemix rules refer to the New Zealand Casemix Framework for Publicly Funded Hospitals document available on http://www.nzhis.govt.nz/moh.nsf/pagesns/300
1. Carotid stenosis with angioplasty
When assigning any of the codes from I65 Occlusion and stenosis of precerebral arteries, not resulting in cerebral infarction as the principal diagnosis, with any procedure code from block [754] Transluminal balloon angioplasty the grouper assigns an error DRG.
Example:
Principal Diagnosis
I65.2 Occlusion and stenosis of carotid artery
Procedure
35309-07 [754] Percutaneous transluminal balloon angioplasty with stenting, multiple stents
Solution:
Do not change or adjust your coding practice. This issue was taken to the Costweight Group in 2006 and thoroughly investigated. A mapping adjustment has been included in the New Zealand batch grouper. Subsequent editions of the grouper have been amended. Therefore, the event will not group to the error DRG 901Z in the NMDS.
Update 2008:
The New Zealand batch grouper has been adjusted to group these cases to NZDRG B04M Extracranial Vascular Procedures.
2. Embolisation procedures
The assignment of the procedure 35321-06 [768] Transcatheter embolisation of blood vessel, pelvis with conditions such as neoplasm’s appears to be grouping to the error DRG 901Z.
Example:
Principal Diagnosis
D25.9 Leiomyoma of uterus, unspecified
Procedure
35321-06 [768] Transcatheter embolisation of blood vessel, pelvis
Solution:
Do not change or adjust your coding practice. This issue has been submitted to the Costweight Group and AIHW. AIHW has notified the Ministry of Health that a fix will occur in the next edition of the grouper. The sector will be informed by the Costweight Group of the action that will be taken in New Zealand while we are using the current grouper version 5.0.
Update 2008:
The Costweight Group is currently investigating these cases, and has advised there is no solution at this time; therefore, no adjustments have been made for the 2008/09 financial year.
3. Percutaneous drainage of intra-abdominal abscess
Any intra-abdominal abscess, for example liver and pelvic, drained via percutaneous approach (as opposed to open) will incur an error DRG 901Z.
Example:
Principal Diagnosis
K75.0 Abscess of liver
Procedure
30224-01[987] Percutaneous drainage of intra-abdominal abscess, haematoma or cyst
Solution:
Do not change or adjust your coding practice. This issue has been submitted to the Costweight Group and AIHW. AIHW has notified the Ministry of Health that a fix has already occurred in the latest version (5.2) of the grouper. The sector will be informed by the Costweight Group of action that will be taken in New Zealand while using the current grouper version 5.0.
Update 2008:
The Costweight Group is currently investigating these cases, and has advised there is no solution at this time; therefore, no adjustments have been made for the 2008/09 financial year. Revenue allocation has been checked and is appropriate for these cases.
4. Follow up care
The following example was raised as a potential error DRG issue with the use of codes from Z42 Follow up care involving plastic surgery.
Example:
Principal Diagnosis
Z42.0 Follow-up care involving plastic surgery of head and neck
Additional Diagnosis
M95.2 Other acquired deformity of head
Procedure
45797-01 [1697] Osseointegration procedure, fixation of transcutaneous abutment for attachment of prosthetic ear
Solution:
An investigation on data retrieved from the NMDS for the period 1 July 2004 to 1 July 2007 with the code of Z42.0 Follow-up care involving plastic surgery of head and neck as either a principal or additional diagnosis is currently being performed.
The preliminary findings show there are 13 cases that have resulted in the error DRG 901Z. However, there appears to be no definitive trend highlighting there is a consistent pathway error at this stage.
Both the AIHW and the Costweight Group have been informed and are assisting the Ministry of Health with this investigation. In the meantime coders are advised not to change or adjust coding practice and again to contact either Mary-Ellen or Tracy with any error DRG 901Z cases that you might have as a result of using codes from Z42 Follow up care involving plastic surgery.
Update 2008:
The Costweight Group is currently investigating these cases.
5. Nerve stimulation procedure
The assignment of codes for angina or faecal incontinence as principal diagnosis with procedure codes for insertion of epidural/sacral electrodes the grouper assigns error DRG 901Z. See the two examples listed below:
Example 1:
Principal Diagnosis
I20.9 Angina pectoris, unspecified
Procedures
39134-01 [1604] Insertion of subcutaneously implanted neurostimulator
39130-00 [43] Percutaneous insertion of epidural electrodes
Example 2:
Principal Diagnosis
R15 Faecal incontinence
Procedures
39134-01 [1604] Insertion of subcutaneously implanted neurostimulator
32213-00 [940] Insertion of sacral nerve electrodes
Solution:
Both the AIHW and the Costweight Group have been informed and are assisting the Ministry of Health with this investigation. AIHW have checked later versions of the grouper and the grouping remains at 901Z for the incontinence and angina. The National Centre of Classification in Health (NCCH) have advised new procedure codes relating to sacral nerve stimulators for faecal incontinence have been developed for sixth edition. Coders are advised not to change or adjust coding practice. The sector will be informed by the Costweight Group of action that will be taken in New Zealand while using the current grouper version 5.0.
Update 2008:
The Costweight Group is currently investigating these cases, and has advised there is no solution at this time; therefore, no adjustments have been made for the 2008/09 financial year.
6. Procedure for stress incontinence, male
The procedures 37044-00 [1109] Retropubic procedure for stress incontinence, male and 37044-03 [1109] Revision of retropubic procedure for stress incontinence, male, with the principal diagnosis of stress incontinence will result in the error DRG 901Z.
Example 1:
Principal Diagnosis
N39.3 Stress incontinence
Procedure
37044-00 [1109] Retropubic procedure for stress incontinence, male
Example 2:
Principal Diagnosis
N39.3 Stress incontinence
Procedure
37044-03 [1109] Revision of retropubic procedure for stress incontinence, male
Solution:
Data retrieved from the NMDS for the period 1 July 2005 to 30 June 2006 for the procedure codes listed above and with the principal diagnosis of stress incontinence, identified only two other cases reported that resulted in the error DRG 901Z.
The Costweight Group has been informed; however, it is unlikely there will be a NZDRG created for these few events being reported. These cases will group to the correct DRG when we move to an updated version. Revenue allocation has been checked and is appropriate for these cases.
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