Skip to main content

T71.9XXA ICD-10-CM Code: Asphyxiation due to unspecified cause, initial encounter

Compare with another codeCheck this code on a claim

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Coding at a Glance

7th character
Required — see the character table on this page
Tabular directives
5 inclusion terms · 7 Excludes1 · 6 code-also instructions

Billable · FY2027A valid, specific ICD-10-CM code, reportable for dates of service in FY2027.

What you need to know

Source: CMS/NCHS Official ICD-10-CM tabular notes, quoted. From the CMS/NCHS tabular list for the release in force. A note the category or block publishes applies to this code too; the Instructions section marks which is which.

Excludes1Never report with this code
  • acute respiratory distress (syndrome) (J80)
  • anoxia due to high altitude (T70.2)
  • asphyxia NOS (R09.01)
  • asphyxia from carbon monoxide (T58.-)

+3 more in Instructions

Code alsoMay be needed with this code
  • , if applicable, place of occurrence, such as:
  • highway rest stop (Y92.523)
  • school (private) (public) (state) as the place of occurrence of the external cause (Y92.21-)
  • service areas as the place of occurrence of the external cause (Y92.52-)

+2 more in Instructions

IncludesWhat this code covers
  • Suffocation (by strangulation) due to unspecified cause
  • Suffocation NOS
  • Systemic oxygen deficiency due to low oxygen content in ambient air due to unspecified cause
  • Systemic oxygen deficiency due to mechanical threat to breathing due to unspecified cause

+1 more in Instructions

Most relevant related codes MedCoder-derived

Read off the official notes above and this code’s own position in the tabular list. Which to report is a documentation question; Compare shows the two side by side.

CompareCheck ClaimView Related Codes

Inpatient Payment Groups (MS-DRG)

Potential MS-DRG participation — not a DRG assignment.

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v44, Appendix B.

  • MS-DRG 922 — OTHER INJURY, POISONING AND TOXIC EFFECT DIAGNOSES WITH MCC (MDC 21)
  • MS-DRG 923 — OTHER INJURY, POISONING AND TOXIC EFFECT DIAGNOSES WITHOUT MCC (MDC 21)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for T71.9XXA in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Notes without a marker are published on T71.9XXA itself; “inherited from” names the category or block whose note applies here.

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Suffocation (by strangulation) due to unspecified cause
  • Suffocation NOS
  • Systemic oxygen deficiency due to low oxygen content in ambient air due to unspecified cause
  • Systemic oxygen deficiency due to mechanical threat to breathing due to unspecified cause
  • Traumatic asphyxia NOS

Source: inherited from T71.9

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Source: inherited from T71

Code Also

Additional codes that may be required to fully describe the encounter.

  • Code also, if applicable, place of occurrence, such as:
  • highway rest stop (Y92.523)
  • school (private) (public) (state) as the place of occurrence of the external cause (Y92.21-)
  • service areas as the place of occurrence of the external cause (Y92.52-)
  • single-family non-institutional (private) house as the place of occurrence of the external cause (Y92.01-)
  • transport vehicle as the place of occurrence of the external cause (Y92.81-)

Source: inherited from T66-T78

7th Character Guide

"The appropriate 7th character is to be added to each code from category T71"

  • A — initial encounter (this page’s code)
  • D — subsequent encounter
  • S — sequela

How the encounter character is assigned. “Initial encounter” means the patient is receiving active treatment for the condition — it is not limited to the first visit, and a different or new provider giving active treatment still assigns it. “Subsequent encounter” covers care during the healing or recovery phase after active treatment. “Sequela” is for complications or conditions that arise as a direct result of the original condition.

ICD-10-CM Official Guidelines for Coding and Reporting, Section I.C.19.a (paraphrased by MedCoder).

Variant codes in this family

T71.9XXA, T71.9XXD, T71.9XXS

Character meanings are CMS's official 7th-character extensions for this family, as carried in each variant code's official description; variant codes are registry rows. The explanation of how the encounter character is assigned is MedCoder editorial, distinct from the official content above it.

Coder workflow for T71.9XXA

MedCoder structured workflow — derived from this code’s own official record

Before you code T71.9XXA

  1. Unspecified does not mean incorrect. When the record gives no greater specificity, T71.9XXA may be the appropriate code. Check the record for detail that supports a more specific sibling. An unspecified code is for records that do not provide the detail a more specific code needs; a query, not an assumption, is the route to specificity (Guidelines I.A.9.b, I.B.18).

    See the relationships section · Guide: Other vs unspecified (NEC vs NOS) →

  2. A 7th character is required in this family. Confirm the documented encounter: initial (active treatment), subsequent (healing or recovery phase), or sequela. This page’s code carries “A”. “Initial” means active treatment, not the first visit (Guidelines I.C.19.a).

    See the 7th Character Guide · Guide: 7th characters: initial, subsequent, sequela →

  3. T71.9XXA’s title joins a condition with an associated condition or complication. Confirm each component is documented. Where the classification presumes the link through the “with” convention, only a provider statement that the conditions are unrelated defeats it. A combination code is assigned only when it fully identifies the documented conditions; a required second code for the stage, type or manifestation is still reported when the notes ask for it (Guidelines I.B.9, I.A.15).

    Guide: Combination codes →

  4. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with T71.9XXA. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

    See the official tabular notes

Choose the right path

  1. Does the record document the detail a more specific sibling code needs?
    Yes → Review the specific siblings in this subcategory.
    No → Continue — T71.9XXA is appropriate when the documentation goes no further.
  2. Does the documentation support a condition named in T71.9XXA’s Excludes1 note?
    Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
    No → Continue.

    ReviewJ80, T70.2, R09.01, T58, T17, T59

  3. Is the encounter phase documented — active treatment, healing or recovery, or a sequela?
    Yes → Assign the matching 7th character; the variant codes are in the 7th Character Guide.
    No → The code is invalid without its 7th character — query for the missing element.

Consider T71.9XXA. Then review the Code Also note, and confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement
Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
Encounter type
Active treatment, healing or recovery phase, or sequela — the basis of the 7th character (Guidelines I.C.19.a).
The associated condition or complication
Whether the associated condition the title names is documented; the “with” convention presumes some links, and a provider statement that the conditions are unrelated defeats it (Guidelines I.A.15).
Any detail beyond this code’s title
What the record states that a more specific sibling code would capture — or its absence, which itself supports the unspecified code.

Official instructions as workflow

  • Excludes1 — check before selecting T71.9XXA(7 notes)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with T71.9XXA: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareJ80, T70.2, R09.01, T58, T17, T59

    See the official tabular notes · Guidelines I.A.12.a

  • Code Also — related condition(6 notes)

    Coding workflow: Review the related condition when both are documented and the instruction applies. A Code Also note does not fix sequencing; the order follows the circumstances of the encounter.

    ReviewY92.523, Y92.21, Y92.52, Y92.01, Y92.81

    See the official tabular notes · Guidelines I.A.17

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: The provider documents the condition in the terms of this code’s title and records no further detail.

Coding question: Is a more specific sibling code supportable?

Path: Review the subcategory for a sibling that names the missing detail.

Reason: A more specific code needs documentation of the distinguishing element; without it the unspecified code is appropriate, and a provider query is the route to specificity (Guidelines I.A.9.b, I.B.18).

Documentation: Both the condition T71.9XXA describes and a condition named in its Excludes1 note are documented for the same encounter.

Coding question: Can both codes be reported?

Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.

Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).

ReviewJ80, T70.2, R09.01, T58, T17, T59

Documentation: The patient returns during the healing or recovery phase after active treatment of the same condition.

Coding question: Which 7th character applies?

Path: Review the official 7th-character definitions for this family in the 7th Character Guide.

Reason: “Initial encounter” means active treatment, not the first visit; care during recovery takes “subsequent encounter”, and a complication arising from the original condition takes “sequela” (Guidelines I.C.19.a).

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Don’t confuse T71.9XXA with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of T71.9XXA — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

  • J80— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of acute respiratory distress (syndrome) moves the case to J80; the two are not reported together unless documented as unrelated.

    Full comparison: T71.9XXA vs J80 →

  • T70.2— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of anoxia due to high altitude moves the case to T70.2; the two are not reported together unless documented as unrelated.

    Full comparison: T71.9XXA vs T70.2 →

  • R09.01— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of asphyxia NOS moves the case to R09.01; the two are not reported together unless documented as unrelated.

    Full comparison: T71.9XXA vs R09.01 →

  • T58— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of asphyxia from carbon monoxide moves the case to T58; the two are not reported together unless documented as unrelated.

    Full comparison: T71.9XXA vs T58 →

  • T17— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of asphyxia from inhalation of food or foreign body moves the case to T17; the two are not reported together unless documented as unrelated.

    Full comparison: T71.9XXA vs T17 →

  • T59— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of asphyxia from other gases, fumes and vapors moves the case to T59; the two are not reported together unless documented as unrelated.

    Full comparison: T71.9XXA vs T59 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Coding context

Guidelines, coding notes, decision aids, relationships (with MS-DRG and CCSR classification), hierarchy, HCC, coverage and the context map: what a coder reaches for after the core. Each section names whether it is official source data, a MedCoder-derived relationship or MedCoder editorial.

Code Overview

Asphyxiation due to unspecified cause, initial encounter is a billable ICD-10-CM diagnosis code (T71.9XXA).

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Decision Points

The directives on this code's own record, as a pre-claim checklist.

  1. A 7th character applies in this family. Confirm the documented encounter matches the character assigned. See the official 7th-character definitions and this code’s variants
  2. 6 Code Also notes — a second code may apply; the guidelines leave its sequencing to the circumstances of the encounter. See the Code Also notes
  3. 7 Excludes1 entries — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes

Checklist rows are derived from this code's own official directives; the wording of each check is MedCoder editorial. The official notes themselves are in the sections each row links to.

Verify Before Coding

  • CC as a secondary diagnosis (FY2027). Can raise the stay's MS-DRG severity tier.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder-derived relationships — computed from published CMS and AHRQ datasets

Other codes that name T71.9XXA or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 1 Excludes1 note: R09.0 — Asphyxia and hypoxemia (via T71.-).

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

MS-DRG Grouper Relationships (FY2027)

Potential MS-DRG participation — not a DRG assignment.

FY2027 MS-DRG: CC — Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 39 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 2 MS-DRGs: DRG 922 (MDC 21), DRG 923 (MDC 21).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):INJ021 — Effect of other external causes, initial encounter (default); EXT017 — External cause codes: suffocation/inhalation; initial encounter; EXT020 — External cause codes: intent of injury, accidental/unintentional.

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same clinical process (MS-DRG)

Acts as CC — raises the severity of other admissions. CMS groups these diagnoses into one MS-DRG principal-diagnosis exclusion process — a CC/MCC on this list never raises severity when the principal diagnosis is also on it.

T71.154A — Asphyxiation due to smothering in furniture, undetermined, initial encounter, T71.161A — Asphyxiation due to hanging, accidental, initial encounter, T71.162A — Asphyxiation due to hanging, intentional self-harm, initial encounter, T71.163A — Asphyxiation due to hanging, assault, initial encounter, T71.164A — Asphyxiation due to hanging, undetermined, initial encounter, T71.191A — Asphyxiation due to mechanical threat to breathing due to other causes, accidental, initial encounter, T71.192A — Asphyxiation due to mechanical threat to breathing due to other causes, intentional self-harm, initial encounter, T71.193A — Asphyxiation due to mechanical threat to breathing due to other causes, assault, initial encounter, T71.194A — Asphyxiation due to mechanical threat to breathing due to other causes, undetermined, initial encounter, T71.20XA — Asphyxiation due to systemic oxygen deficiency due to low oxygen content in ambient air due to unspecified cause, initial encounter, T71.21XA — Asphyxiation due to cave-in or falling earth, initial encounter, T71.221A — Asphyxiation due to being trapped in a car trunk, accidental, initial encounter, T71.222A — Asphyxiation due to being trapped in a car trunk, intentional self-harm, initial encounter, T71.223A — Asphyxiation due to being trapped in a car trunk, assault, initial encounter, T71.224A — Asphyxiation due to being trapped in a car trunk, undetermined, initial encounter, T71.231A — Asphyxiation due to being trapped in a (discarded) refrigerator, accidental, initial encounter, T71.232A — Asphyxiation due to being trapped in a (discarded) refrigerator, intentional self-harm, initial encounter, T71.233A — Asphyxiation due to being trapped in a (discarded) refrigerator, assault, initial encounter, T71.234A — Asphyxiation due to being trapped in a (discarded) refrigerator, undetermined, initial encounter, T71.29XA — Asphyxiation due to being trapped in other low oxygen environment, initial encounter, +18 more

Same injury, other encounter phase

Same injury, coded at a different phase of treatment via the 7th character.

T71.9XXD — Asphyxiation due to unspecified cause, subsequent encounterCompare T71.9XXA vs T71.9XXD →, T71.9XXS — Asphyxiation due to unspecified cause, sequelaCompare T71.9XXA vs T71.9XXS →

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical categories (Effect of other external causes, initial encounter, External cause codes: suffocation/inhalation; initial encounter, External cause codes: intent of injury, accidental/unintentional).

T71.21XA — Asphyxiation due to cave-in or falling earth, initial encounter, T71.221A — Asphyxiation due to being trapped in a car trunk, accidental, initial encounter, T71.222A — Asphyxiation due to being trapped in a car trunk, intentional self-harm, initial encounter, T71.223A — Asphyxiation due to being trapped in a car trunk, assault, initial encounter, T71.224A — Asphyxiation due to being trapped in a car trunk, undetermined, initial encounter, T71.231A — Asphyxiation due to being trapped in a (discarded) refrigerator, accidental, initial encounter, T71.232A — Asphyxiation due to being trapped in a (discarded) refrigerator, intentional self-harm, initial encounter, T71.233A — Asphyxiation due to being trapped in a (discarded) refrigerator, assault, initial encounter, T71.234A — Asphyxiation due to being trapped in a (discarded) refrigerator, undetermined, initial encounter, T71.29XA — Asphyxiation due to being trapped in other low oxygen environment, initial encounter, T73.0XXA — Starvation, initial encounter, T73.1XXA — Deprivation of water, initial encounter, T73.2XXA — Exhaustion due to exposure, initial encounter, T73.3XXA — Exhaustion due to excessive exertion, initial encounter, T73.8XXA — Other effects of deprivation, initial encounter, T73.9XXA — Effect of deprivation, unspecified, initial encounter, T74.A1XA — Adult financial abuse, confirmed, initial encounter, T74.A2XA — Child financial abuse, confirmed, initial encounter, T75.00XA — Unspecified effects of lightning, initial encounter, T75.01XA — Shock due to being struck by lightning, initial encounter, +2436 more

Contextual Map

Every relationship of T71.9XXA in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run T71.9XXA with this related code in Claim Check

Hierarchy

Referenced by Excludes1 notes

Clinical classification (CCSR)

MS-DRG Grouper

MDC crossing

  • MDC 21 — Injuries, Poisonings and Toxic Effects of Drugs[MDC crossing]: “Injuries, Poisonings and Toxic Effects of Drugs — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 32,063 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2027

Nearest codes (40)

Change history

  • FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Reference

Index terms and tables, published questions and FAQ, every source behind this page with its release and checksum, the date-of-service check and the complete change history.

Common coding questions

MedCoder editorial

Does T71.9XXA require a 7th character?

Yes. The appropriate 7th character is to be added to each code from category T71.

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data
CMS/CDC ICD-10-CM FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 2026) Release, file and checksum · Publisher’s page
Inpatient payment groups Official source data
CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v44 Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data
CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder-derived relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder editorial explanation
Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 20, 2026 · All releases and sources

Labels on this page: Official source data · MedCoder-derived relationship · MedCoder editorial explanation. How to read the labels · All data sources and release dates · CMS coding rules

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "T71.9XXA — Asphyxiation due to unspecified cause, initial encounter." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/t71.9xxa-asphyxiation-due-to-unspecified-cause-initial-encounter

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Asphyxiation due to unspecified cause, initial encounter

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027, and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to T71.9XXA in its code family, with their registry titles.

View all codes in the T71 family