2026 ICD-10-CM Diagnosis Code T71.21XAAsphyxiation due to cave-in or falling earth, initial encounter
T71.21XA is a billable ICD-10-CM diagnosis code for asphyxiation due to cave-in or falling earth, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 922 through 923. Coders also document this condition as accidental mechanical suffocation by falling earth. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Effect of other external causes, initial encounter; External cause codes: intent of injury, accidental/unintentional; and External cause codes: suffocation/inhalation; initial encounter.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Accidental mechanical suffocation by falling earth
- Accidental mechanical suffocation by falling material
- Accidental mechanical suffocation by rockfall in mining
- Asphyxia by burial under powder or solid matter
- Asphyxia by entrapment with mouth and nose blocked
- Asphyxia by obstruction of mouth and nose
- Asphyxiation by sustained compression of chest
- Suffocation by cave-in
- Suffocation by mechanical cause
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Asphyxiation (T71). Use the following options for the applicable episode of care:
- A - initial encounter
- D - subsequent encounter
- S - sequela
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Convert T71.21XA to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About T71.21XAOverview
Is T71.21XA (Asphyxiation due to cave-in or falling earth) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report asphyxiation due to cave-in or falling earth, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in T71.21XA mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for asphyxiation due to cave-in or falling earth, such as an emergency visit or first evaluation.
What MS-DRG does T71.21XA group to?
When asphyxiation due to cave-in or falling earth, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 922, 923, with relative weights from 1.0177 to 1.7494 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of T71.21XA?
Under the General Equivalence Mappings, asphyxiation due to cave-in or falling earth, initial encounter converts to ICD-9-CM 994.7 (asphyxiation/strangulat) and E913.3 (cave-in NOS). The mapping is approximate, so confirm the match fits the documentation.
Footnotes
[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.
