Leverage the CMS Website for Acute Inpatient Hospital Coding Guidance

By Megan DeVoe, CCS

Editor’s Note: This is the second article in a three-part series on how to master the information available on the Centers for Medicare and Medicaid Services website.

Inpatient coding can be very challenging, especially now that health information management professionals are in the thick of using ICD-10-CM/PCS. It will be several years until all the kinks are worked out of the ICD-10 classification system and coding professionals are as comfortable with ICD-10 as they were with ICD-9-CM. This will happen eventually, but in the meantime it is important for coding professionals to share with each other any useful official information that can be utilized to substantiate and guide coding.

There is a treasure trove of information found on the Centers for Medicare and Medicaid Services (CMS) website for acute hospital inpatient prospective payment system (IPPS) coding. The challenge is finding it and understanding what you are looking at. This article takes a closer look to offer some guidance on leveraging this resource.

MS-DRG Guidance

First, let’s look at the Medicare Severity Diagnosis Related Groups (MS-DRGs) information. The most up-to-date MS-DRG definition manual can be found on the fiscal year (FY) 2018 Final Rule and Correction Notice Data Files page. See the graphic on page 57 for what this looks like.

Instead of downloading the ICD-10 MS-DRG Definitions Manual Files v35 (Updated September 12, 2017) ZIP file (available at www.cms.gov/Medicare/Medicare-Fee-for-Service-Payment/AcuteInpatientPPS/Downloads/FY2018-CMS-1677-FR-MS-DRG-Definitions-Manual.zip), it is easier to just bookmark the link to the web version of the manual, which is www.cms.gov/ICD10Manual/version35-fullcode-cms/fullcode_cms/P0001.html. This link can be found at the bottom of the FY 2018 Final Rule and Correction Notice Data Files webpage in the related links section.

The MS-DRG manual is now in electronic format where the data can be shown either in MS-DRG order or Major Diagnostic Category (MDC) order. When coding, if you are encountering a MS-DRG result that does not make sense, it is very useful to use this manual to review the codes assigned to a particular MS-DRG. The manual will list ICD-10-CM and ICD-10-PCS codes included in the MS-DRG and may also include information on sequencing and discharge dispositions. Sometimes the codes and criteria listed may be surprising.

For example, the excerpt from ICD-10-CM/PCS MS-DRG v35.0 Definitions Manual, MDC 03 Diseases and Disorders of the Ear, Nose, Mouth and Throat, Other Ear, Nose, Mouth and Throat O.R. Procedures, DRGs 133 and 134 included in the sidebar below shows which ICD-10-PCS codes are included in this DRG.

The appendices listed at the bottom of the main MS-DRG webpage list the codes defined as Complications or Comorbidities (CCs) and Major Complications or Comorbidities (MCCs), as well as the listing of the Operating Room Procedures and Hospital-Acquired Conditions (HACs). This can help to identify and resolve any questions relating to a surprising CC/MCC grouping result.

Coding professionals will want to make sure they are reviewing the MS-DRG manual that correlates with the date of service being coded. Typically, the MS-DRG manuals are updated in October of each year.

IPPS Guidance

Next, let’s review the IPPS editing information that is available on the CMS website. The Definition of Medicare Code Edits (MCE) file can be found on the FY 2018 Final Rule and Correction Notice Data Files page (www.cms.gov/Medicare/Medicare-Fee-for-Service-Payment/AcuteInpatientPPS/Downloads/FY2018-CMS-1677-FR-Code-Edits.zip). Like the Outpatient Code Editor (OCE), these files describe the inpatient edits one may receive while coding. There are only two files in this ZIP folder. The Definitions of Medicare Code Edits_v35 file will contain information on the codes included in an edit as well as an explanation of any criteria used to trigger the edit.

When an MCE edit is encountered that you do not agree with or understand, this is the first place you want to look to verify the validity of the edit. Many edit types may be encountered while coding. Knowing how to recognize these edits and correctly resolve them will ensure accurate code assignment. MCE edits cannot be ignored and supersede all other software edits for Medicare IPPS patients.

The Definitions of Medicare Code Edits file will list any gender- or age-specific ICD-10-CM codes and even non-covered ICD-10-CM procedure codes. For example, if an obstetric code is accidentally assigned to a 99-year-old female, that will trigger an Age Conflict edit, indicating that the Medicare Code Editor has detected an inconsistency between the patient’s age and the diagnosis. In the Definitions of Medicare Code Edits file, all the codes that are considered maternity diagnoses and the age ranges for those codes are listed.

See the sidebar above for an excerpt from the Definitions of Medicare Code Edits file, showing an example of the maternity diagnoses list.

The MCE edits are typically updated each October along with the MS-DRG grouper. When an MCE edit is encountered, a coding professional may notice they will receive MS-DRG 999 Ungroupable. These edits are incorporated into the grouper and indicate that a critical error has occurred that is preventing grouping.

The IPPS information on the CMS website is much less overwhelming than the outpatient information and more straightforward. Bookmark these sites so that when questions arise you are well equipped to substantiate your code assignment.

Megan DeVoe (mdevoe@earthlink.net) is senior product specialist at TruCode.