Alphabetic Index FY2027

Z99.81

Dependence on supplemental oxygen

FY2027Chapter 21: Factors influencing health status and contact with health services/Z77–Z99 Persons with potential health hazards related to family and personal history and certain conditions influencing health status

BillableComplete code, valid to report
Care settingsIPF Comorbidity · Chronic Obstructive Pulmonary Disease and Sleep Apnea

Z99.81 (also written Z9981) is a billable ICD-10-CM diagnosis code for dependence on supplemental oxygen. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 7 codes in category Z99 (Dependence on enabling machines and devices, not elsewhere classified). The Alphabetic Index lists it under 2 entries. Its coding notes include a Code also instruction.

Guidelines tip

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

A status code is not the same as a history code. It is not added when the diagnosis code already includes the status.

Guidelines I.C.21.c.3Status Z codesRead the official text

Code also

Two codes may be needed to describe the condition. This note gives no sequencing order.

Also from chapter/block level (1 note)
Inherited from Z77–Z99 Persons with potential health hazards related to family and personal history and certain conditions influencing health status
  • any follow-up examination (Z08-Z09)

Care settings

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

IPF Comorbidity

On the CMS IPF comorbidity list.

Comorbidity categoryFactor
Chronic Obstructive Pulmonary Disease and Sleep Apnea1.09
It counts as a comorbidity when reported as a secondary diagnosis and actively treated during the stay. An IPF receives only one adjustment within a category and can receive adjustments in more than one category.

Source: CMS IPF PPS FY 2027 final rule (CMS-1847-F), Addendum B-3 (comorbidity codes with adjustment factor); effective for discharges on or after October 1, 2026

Inclusion terms

Conditions classified to this code.

This code
  • Dependence on long-term oxygen

Notes

Also from chapter/block level (3 notes)
Inherited from Chapter 21 Factors influencing health status and contact with health services
  • Z codes represent reasons for encounters. A corresponding procedure code must accompany a Z code if a procedure is performed. Categories Z00-Z99 are provided for occasions when circumstances other than a disease, injury or external cause classifiable to categories A00-Y89 are recorded as 'diagnoses' or 'problems'. This can arise in two main ways:
    • (a) When a person who may or may not be sick encounters the health services for some specific purpose, such as to receive limited care or service for a current condition, to donate an organ or tissue, to receive prophylactic vaccination (immunization), or to discuss a problem which is in itself not a disease or injury.
    • (b) When some circumstance or problem is present which influences the person's health status but is not in itself a current illness or injury.

Alphabetic Index terms

Terms the official Alphabetic Index lists for this code. 2 entries