Alphabetic Index FY2027

T88.51XA

Hypothermia following anesthesia, initial encounter

FY2027Chapter 19: Injury, poisoning and certain other consequences of external causes/T80–T88 Complications of surgical and medical care, not elsewhere classified

BillableComplete code, valid to report
Care settingsHome Health Primary · MMTA - Other

T88.51XA (also written T8851XA) is a billable ICD-10-CM diagnosis code for hypothermia following anesthesia, initial encounter. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 39 codes in category T88 (Other complications of surgical and medical care, not elsewhere classified). The Alphabetic Index lists it under 2 entries. Its 7th character, A, means initial encounter. Its coding notes include a Use additional code instruction and 33 Excludes2 entries.

7th character

Category T88 requires a 7th character. T88.51 has only 5 characters, so a placeholder X fills the 6th position.

Assembled code T88.51XA Open code

Guidelines tips

From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.

The 7th character depends on whether the patient is in active treatment, not on who sees the patient. An aftercare Z code is not used for injury aftercare.

Guidelines I.C.19.aInjuries: application of 7th charactersRead the official text

A complication code needs the provider's documented cause-and-effect link between the care and the condition. Some T codes already include the type of procedure, so no external cause code is needed.

Guidelines I.B.16; I.C.19.g.4Complications of careRead the official text

Use additional code

Add the listed code as a secondary code, if known.

Inherited from T88.5 Other complications of anesthesia
  • code for adverse effect, if applicable, to identify drug (T41.- with fifth or sixth character 5)
Also from chapter/block level (4 notes)
Inherited from T80–T88 Complications of surgical and medical care, not elsewhere classified
  • code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)
  • code(s) to identify the specified condition resulting from the complication
  • code to identify devices involved and details of circumstances (Y62-Y82)
Inherited from Chapter 19 Injury, poisoning and certain other consequences of external causes
  • code to identify any retained foreign body, if applicable (Z18.-)

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Inherited from T88 Other complications of surgical and medical care, not elsewhere classified
  • complication following infusion, transfusion and therapeutic injection (T80.-)
  • complication following procedure NEC (T81.-)
  • complications of anesthesia in labor and delivery (O74.-)
  • complications of anesthesia in pregnancy (O29.-)
  • complications of anesthesia in puerperium (O89.-)
  • complications of devices, implants and grafts (T82-T85)
  • complications of obstetric surgery and procedure (O75.4)
  • dermatitis due to drugs and medicaments (L23.3, L24.4, L25.1, L27.0-L27.1)
  • poisoning and toxic effects of drugs and chemicals (T36-T65 with fifth or sixth character 1-4)
  • specified complications classified elsewhere
Also from chapter/block level (23 notes)
Inherited from T80–T88 Complications of surgical and medical care, not elsewhere classified
  • any encounters with medical care for postprocedural conditions in which no complications are present, such as:
    • artificial opening status (Z93.-)
    • closure of external stoma (Z43.-)
    • fitting and adjustment of external prosthetic device (Z44.-)
    • burns and corrosions from local applications and irradiation (T20-T32)
    • complications of surgical procedures during pregnancy, childbirth and the puerperium (O00-O9A)
    • mechanical complication of respirator [ventilator] (J95.850)
    • poisoning and toxic effects of drugs and chemicals (T36-T65 with fifth or sixth character 1-4 or 6)
    • postprocedural fever (R50.82)
  • specified complications classified elsewhere, such as:
Inherited from Chapter 19 Injury, poisoning and certain other consequences of external causes
  • birth trauma (P10-P15)
  • obstetric trauma (O70-O71)

Care settings

How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.

Home Health Primary

Accepted as the primary (principal) diagnosis on a home health claim. The Home Health Grouper assigns it to the MMTA - Other clinical group.

Source: CMS Home Health Grouper Software v07.2.26, effective October 1, 2026

Notes

Also from chapter/block level (2 notes)
Inherited from Chapter 19 Injury, poisoning and certain other consequences of external causes
  • Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
  • The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.

Alphabetic Index terms

Terms the official Alphabetic Index lists for T88.51. This code adds the 7th character. 2 entries