Diagnosis Coding Insight: ICD-10 Updates for Wound Care

The ICD-10-CM codes that are associated with wound care for 2019 became effective Oct. 1, 2018. The codes fit into two major categories: new and revised. Although this article will only review the wound care-related code changes, readers can view the entire list of new and revised codes in Table 6 A-K in the final rule of the Inpatient Prospective Payment System.¹ This article will also review the Chapter 19 coding guidelines for proper assignment of the 7th character for ICD-10, a topic that has continued to generate many questions and points of confusion among those throughout the wound care industry.

NEW WOUND CARE-RELATED CODES
The 2019 ICD-10 codes for wound care are displayed in Table 1 (page 26), which is divided into five sections. Section 1 identifies new codes for disorders of metabolism and lipids; Section 2 lists new codes for cerebral infarctions/arteriopathy and leukoencephalopathy; Section 3 displays new codes for infections of obstetric wounds; Section 4 shows new codes for postoperative infections; and Section 5 shows the new code for family history, other disorder, of lipoprotein metabolism and other lipidemia.

REVISED WOUND CARE-RELATED CODES
The revised code titles for existing ICD-10 codes are displayed in Table 2 (page 26). The revisions include codes for occlusion and stenosis of vertebral and carotid arteries, as well as codes for infarctions due to thrombosis of specific sites. Wound care professionals should be interested in the revisions of the codes related to non-pressure ulcers “of other sites with and without necrosis,” “for chronic osteomyelitis of the humerus,” and “for body mass index (BMI) of 50-59.9.”

REQUIRED IMPLEMENTATION ACTIONS FOR NEW & REVISED CODES
After reviewing the new and revised codes, wound care professionals should: 1) share the code changes with clinical and revenue cycle staff; 2) ensure that the new codes are added to the electronic billing systems and forms; and 3) review all pertinent (eg, wound care, cellular and/or tissue-based products [CTPs], hyperbaric oxygen therapy [HBOT], electrical stimulation, electromagnetic therapy) national coverage determinations (NCDs) and local coverage determinations (LCDs) that are updated due to these code changes. The Centers for Medicare & Medicaid Services has already updated the NCDs, and most Medicare Administrative Contractors have updated their LCDs. 

CORRECT USE OF 7TH CHARACTERS IN ICD-10 CHAPTER 19
This author has received numerous questions about the correct use of the “A” “S” and “D” 7th character values. Wound care professionals should always remember that 7th character values are only applicable to codes in Chapter 19 (Injury, Poisoning, and Certain Other Consequences of External Causes) of the ICD-10 code book. They are not required for non-injury ulcer codes outside of Chapter 19. Some commercial payers are asking for 7th character values with non-pressure and pressure ulcer diagnoses. If payers are asking you to provide the 7th character on these diagnosis codes, ask the payers why they are requiring a 7th character on codes that are not in Chapter 19. The payer may not be aware of the Chapter 19 rule. In that case, take the opportunity to educate the payer about the 7th character ICD-10 requirement and request a copy of the commercial policy that requires the 7th character on codes outside of Chapter 19. All injury and poisoning categories (except for fractures) in Chapter 19 have three 7th character value requirements for each applicable code: 1) “A” = initial encounter; 2) “D” = subsequent encounter; and 3) “S” = sequela. Note that categories for traumatic fractures have additional 7th character values. The following are a few appropriate-use tips for each of the three 7th character values:

Initial encounter. Should be used for each encounter when the patient receives active treatment for a condition. This initial encounter “A” character is based on whether the patient was undergoing active treatment for the condition, not whether the physician or other qualified healthcare professional (QHP) saw the patient for the first time. Example: For complication codes, “active treatment” refers to treatment for the condition described by the code, even though it may be related to an earlier precipitating problem. ICD-10 Code T84.50XA — infection and inflammatory reaction due to unspecified internal joint prosthesis, initial encounter — should be used when active treatment was provided for the infection, even though the condition related to the prosthetic device, implant, or graft was placed at a previous encounter. Remember that, in wound care, the diagnosis codes for chronic ulcers and repeat visits while the physician is still providing active treatment (such as debridement, application of CTPs, and HBOT) do not require a 7th character “A” because the chronic ulcer diagnosis codes are not in Chapter 19. A commercial payer may have different definitions than those provided in the ICD-10 coding guidelines. Therefore, wound care professionals should verify commercial payers’ definitions/guidelines for the use of the 7th character, if they are being requested for diagnosis codes outside of Chapter 19. However, because this is an area of great confusion, remember that even though a patient was seen by a new or different physician or other QHP over the course of treatment for an injury, assignment of the 7th character value is based on whether the patient was undergoing active treatment for the condition, not whether a patient was seen for the first time for the condition. 

Subsequent encounter. Should be used for encounters after the patient completes active treatment of the condition and is receiving routine care for the condition during the healing or recovery phase. In wound care, this may be routine postoperative visits after a traumatic wound is closed. The aftercare “Z” codes should not be used to identify subsequent care (eg, assign an acute injury code with the 7th character “D” [subsequent encounter] rather than an aftercare “Z” code. 

Sequela. Should be used for complications or conditions that arise as a result of a condition, such as scar formation after a burn. (Scars are sequelae of the burn.) When using the 7th character “S,” it is necessary to use the injury code that precipitated the sequela and the code for the sequela. The “S” is added only to the injury code. The 7th character “S” identifies the injury responsible for the sequela. The type of sequela is sequenced first, followed by the injury code.

SUMMARY
While the new and revised code lists are not as extensive as last year’s, wound care professionals should review and implement the codes, invest in new ICD-10 code books or software for 2019, and verify that software vendors have updated all billing system components. In addition, wound care professionals should review the 7th character value guidelines for Chapter 19 and challenge commercial payers who attempt to require the 7th character for codes that are not in that chapter. n

Donna Cartwright is senior director of health policy and reimbursement at Integra LifeSciences Corp., Plainsboro, NJ. She is approved as a certified trainer on ICD-10-CM by the American Health Information Management Association and she has been designated as a fellow of the American Health Information Management Association.

Reference 

1. Details for title: FY 2019 final rule tables. CMS. Accessed online: www.cms.gov/medicare/medicare-fee-for-service-payment/acuteinpatientpps/fy2019-ipps-final-rule-home-page-items/fy2019-ipps-final-rule-tables.html