From 3M Health Information Systems
ICD-10 and DRG shifts: Your questions answered
Cheryl: So Donna, I have been getting a lot of questions from clients about ICD-10-CM and PCS lately. I was in elementary school when the last code switch occurred. Can I pick your brain?
Donna: Are you implying that I’m old?
Cheryl: Maybe…but I mean it in the best way! Like I said, I was just a kid when we went from ICD-8 to ICD-9, so you are more of an expert on conversions. Was it as crazy then as it is now?
Donna: ICD-9 was implemented in 1979, but it did not impact reimbursement as ICD-10 does now because DRG payment systems were initiated in the 1980s after the code switch. As of January 1, 1980, a claim had to have an ICD-9-CM diagnosis code. I remember getting a frantic call saying that the claims were printing without the code descriptions. However, all the codes were listed so we just added the appropriate descriptions.
Cheryl: That helps put this change into perspective, but what is happening with all of these procedures that are routing to surgical DRGs when they did not in ICD-9? Did CMS intend for these to route to surgical DRGs?
Donna: CMS’s intention was to replicate the ICD-9-CM version of MS-DRGs. Because of the implementation of a brand new procedure coding system, ICD-10-PCS, there have been a few instances of unintended DRG shifts.
Cheryl: Couldn’t they have anticipated these changes in advance of releasing the codes?
Donna: The ICD-10 MS-DRGs were originally determined using a combination of the GEMs (general equivalency mappings) and other factors and then refined over time. CMS started with an ICD-10 version 27 and has updated yearly since then, so these have been updated at least six times. Basically CMS did not have a natively coded ICD-10 data set to test and so could not have avoided some of the unintended shifts in MS-DRGs.
Cheryl: So, you are saying that CMS will make changes based on review of data natively coded in ICD-10 from claims submitted after October 1, 2015?
Donna: Sort of. There is an on-going process that CMS undertakes every year to evaluate the proper DRG placement of diagnoses and procedures. This is detailed yearly in the proposed rule.
Cheryl: Thanks for the info! As always, I still have a couple more questions. How does CMS decide where to place the codes? Do they use the 3M grouper?
Donna: The CMS-DRG classification logic is in the public domain and is available for purchase from the National Technical Information Service. Hospitals can either install the CMS-DRG grouper or select a vendor that may offer additional services.
Cheryl: Wow, I never knew there was a CMS grouper. How can my clients find out where the codes are mapped to again?
Donna: They are always published in the Definitions Manual, and this is a link to the V33 Definitions Manual.
Cheryl: Ok, last question I promise. What advice should I give to my clients about coding records in ICD-10-PCS?
Donna: It took us 30 years to refine coding in ICD-9 and I would expect that it would take some amount of time to refine the coding in ICD-10. So my advice is, be patient.
Cheryl: Thanks as always Donna. Being a nurse and not a coding professional always makes it a little harder for me to understand the big picture and answer my clients’ questions. Your perspective always helps!
Donna Smith is a project manager with the Consulting Services business of 3M Health Information Systems.
Cheryl Manchenton is a senior inpatient consultant and project manager for 3M Health Information Systems.