Marking Fire Prevention Week with Burn Coding Basics

By Laurie M. Johnson, MS, RHIA, FAHIMA, AHIMA Approved ICD-10-CM/PCS Trainer | October 16, 2023

Oct. 8-14 is National Fire Prevention Week. The diagnosis codes for burns are found in Chapter 19 (Injury, Poisoning, and Certain Other Consequences of External Causes) of ICD-10-CM. The Index entry for burns includes the non-essential modifiers of electricity, flame, hot gas, liquid, or hot object; radiation; steam; and thermal. Another Index entry is corrosion, which includes the non-essential modifiers of injury: acid, caustic, chemical, lime, external, and internal. Both entries are organized by anatomic site and degree of burn. According to the Official Coding and Reporting Guidelines, burns of the eye and internal organs are classified by site, but not degree.

The sequencing of burns is by the highest degree when more than one burn is present. When internal and external burns are present, the sequencing will be based on the circumstances of admission. When the patient is admitted with burns and related conditions, such as smoke inhalation and/or respiratory failure, the circumstances of admission govern the selection of the principal diagnosis or first-listed diagnosis.

Burns of the same anatomic site and laterality are coded to the highest degree. Non-healing burns are coded as acute burns. An infected burn is coded as a burn with an additional code for the infection. When multiple burns are present, code each anatomic site separately. The code for multiple sites should only be used when the medical record documentation does not specify the individual sites.

Code the extent of the burn(s) using T31 (Burns classified according to the extent of body surface involved) or T32 (Corrosions classified according to the extent of body surface involved). The estimation of the involved body surface is based on the rule of 9s: head and neck – 9 percent, anterior or posterior trunk – 18 percent, anterior or posterior leg – 9 percent, each arm – 9 percent, and genitalia is 1 percent.

Next, the coder should assign diagnosis codes for external causes, which identify the source of the burn as well as the place where it occurred. Your state data commission may provide guidance regarding external cause code reporting. For example, I am from the state of Pennsylvania, and the Pennsylvania Health Care Cost Containment Council (PHC4) requires external cause codes on every encounter that a trauma code is reported. This requirement is different from the Official Coding and Reporting Guidelines, which directs providers to report the external cause code on the initial encounter. It is important to note the data reporting requirements for this topic.

The reporting of burns/corrosions is part of trauma reporting. This information is circulated beyond the adjudication of claims, so it is important to be accurate.

Be safe out there!


ICD-10-CM, 2024

Official Coding and Reporting Guidelines, ICD-10-CM, 2024