Updated on: March 16, 2016

Implementation Guides from CMS Outline the Fine Details for ICD-10 Transition

Original story posted on: September 26, 2012

Small hospitals and provider practices can thank the Centers for Medicare & Medicaid Services (CMS) for developing separate ICD-10 “implementation guides” for them to use.

Each guide provides detailed information for planning and executing the ICD-10 transition, and CMS urges providers to use them as a reference “whether you're in the midst of the transition or just beginning.”


In addition to tailored step-by-step plans and customizable templates, the guides include tables and figures full of details that providers need to consider before implementation. CMS states that it created these tools “to help entities clarify staff roles, set internal deadlines and responsibilities, and assess vendor readiness.”

The primary chapter—Implementing ICD-10—is organized into the following phases:

  • Planning
  • Communication and awareness
  • Assessment
  • Implementation
  • Testing
  • Transition.

By the third phase—assessment — CMS delves into the nitty-gritty of the preparation, starting with the business processes affected by ICD-10 and ending with scenario-based vendor assessment. In between are several vital areas of concern related to clinical documentation and reimbursement. A few tips from these sections are provided below.

Clinical Documentation

Although it’s been said many times, CMS says it again: ICD-10 implementation will impact clinical documentation. In fact, increased code detail contained in ICD-10-CM means that required documentation will change substantially. Specifically, states the agency, “ICD-10-CM includes a more robust definition of severity, comorbidities, complications, sequelae, manifestations, causes, and a variety of other important parameters that characterize the patient’s condition.”

As a result, it’s essential that providers accurately represent healthcare services through complete and precise reporting of diagnoses and procedures as well as specific data for clinical decision-making, performance reporting, managed care contracting, and financial analysis.

Even though the number of available ICD-10 codes has grown considerably from the number in ICD-9, CMS points out that many of the new codes only differ in one parameter. For example, nearly 25 percent of the ICD-10-CM codes are the same except for indicating the right side of the patient’s body versus the left. Another 25 percent of the codes differ only in the way they distinguish among “initial encounter,” versus “subsequent encounter,” versus “sequelae.”

Another example: Even though there are more than 1,800 available codes for coding fractures of the radius, there are only approximately 50 distinct recurring concepts. To illustrate this, CMS includes a table that lists individual concepts that should be considered in documentation to support accurate coding of patient conditions for fractures of the radius.

In the implementation guide, CMS also addresses the ICD-10-PCS system and in relation to it summarizes what coders may not want to hear. The proper use of ICD-10 codes with ICD-10-PCS terminology changes what information is needed from the medical record. Professional coders may find it difficult to use existing documentation models to assess proper coding.

For example, if a surgeon dictates in an operative report that he “removed the left upper lobe of the lung,” the coder must recognize that the proper code would include a “resection” of the “left upper lobe.” The coder must recognize that the “left upper lobe” is a complete body part in ICD-10-PCS and that removing a complete body part is defined as a “resection.” The term “removal” now applies only to removing synthetic materials.

Small Hospital Payments

Most “hospital-reimbursement models” will change in the ICD-10 transition, says CMS. To identify the impact of revenue, begin by evaluating the following:

  • Current denial process
  • Current MS-DRG performance
  • Two key thresholds under ICD-10: discharge, not final code (DNFC) and discharge, not final billed (DNFB).

Table 17 of the implementation guide shows seven types of common reimbursement arrangements alongside ICD-10 implementation potential effects. One of the arrangements is, of course, DRGs and other case rates, and CMS explains the potential effects for the new system. Specifically, the process of redefining the MS-DRG grouper for ICD-10 resulted in changes in the grouper logic that may lead to unanticipated mapping errors as compared to the ICD-9 grouper experiences.

  • The ICD-10-based MS-DRGs will likely produce different reimbursement results compared to ICD-9-based MS-DRGs due to the following:
    • Potential changes in coding due to new guidelines and code definitions
    • Potential coding accuracy challenges due to unfamiliarity of coders with these new codes
    • Mapping challenges
    • Changes in complications comorbidities/major complications comorbidities (CC/MCC) assignment may be different in ICD-10 and result in varying payment compared to similar conditions and services in ICD-9 codes.
  • When applying CMS-designed ICD-10 MS-DRGs to a commercial population, MS-DRG assignment (i.e., case mix) may vary more than in a Medicare population.

Tap the Knowledge Base

The above is just skimming the surface of what’s in this one implementation guide. Each of the three listed on the CMS web site at http://cms.gov/Medicare/Coding/ICD10/ProviderResources.html considers the type of provider, although some guidelines may be similar.

Now’s the time to begin or continue with the transition, and CMS appears to be making good on its promise to provide the tools to do it.

Disclaimer: Every reasonable effort was made to ensure the accuracy of this information at the time it was published. However, due to the nature of industry changes over time we cannot guarantee its validity after the year it was published.
Janis Oppelt

Janis keeps the wheel of words rolling for Panacea®'s publishing division. Her roles include researching, writing, and editing newsletters, special reports, and articles for RACMonitor.com and ICD10Monitor.com; coordinating the compliance question of the week; and contributing to the annual book-update process. She has 20 years of experience in topics related to Medicare regulations and compliance.