2026 ICD-10-CM Diagnosis Code T88.53XAUnintended awareness under general anesthesia during procedure, initial encounter

ICD-10-CM Codes›S00–T88›T80-T88›T88

ICD-10-CM T88.53XA
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

T88.53XA is a billable ICD-10-CM diagnosis code for unintended awareness under general anesthesia during procedure, 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 917 through 918. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Complication of other surgical or medical care, injury, initial encounter.

Code Identity

ICD-10-CM Code
T88.53XA
Billable Status
Yes — Valid for Submission
Code Describes
Unintended awareness under general anesthesia during procedure, initial encounter
Short Description
Unintended awareness under general anesth during proc, init
Parent Code
T88.53
Unintended awareness under general anesthesia during procedure

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionT80-T88Complications of surgical and medical care, not elsewhere classified
CategoryT88Other complications of surgical and medical care, not elsewhere classified
This CodeT88.53XAUnintended awareness under general anesthesia during procedure, initial encounter

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Accidental awareness during maintenance of general anesthesia
  • Accidental awareness under general anesthesia
  • Accidental awareness under general anesthesia during emergence or extubation
  • Accidental awareness under general anesthesia during induction or intubation
  • Awareness under general anesthesia
  • Under anesthesia
  • Under general anesthesia

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Other complications of surgical and medical care, not elsewhere classified (T88). 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.

CCSR INJ037
Complication of other surgical or medical care, injury, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Convert T88.53XA to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
995.22 Adv eff anesthesia NOS
Approximate The match is approximate rather than exact.

Code History & ChangesHistory

Replacement T88.53XA replaces the following previously assigned code(s):

  • T88.59XA - Other complications of anesthesia, initial encounter
FY 2018AddedAdded to the ICD-10-CM code setEffective October 1, 2017.
FY 2019–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About T88.53XAOverview

Is T88.53XA a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report unintended awareness under general anesthesia during procedure, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in T88.53XA mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for unintended awareness under general anesthesia during procedure, such as an emergency visit or first evaluation.

What MS-DRG does T88.53XA group to?

When unintended awareness under general anesthesia during procedure, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 917, 918, with relative weights from 0.8571 to 1.5684 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of T88.53XA?

Under the General Equivalence Mappings, unintended awareness under general anesthesia during procedure, initial encounter converts to ICD-9-CM 995.22 (adv eff anesthesia 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.