2027 ICD-10-CM Diagnosis Code P81.0Environmental hyperthermia of newborn

ICD-10-CM Codes›P00–P96›P80-P83›P81

ICD-10-CM P81.0
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

P81.0 is a billable ICD-10-CM diagnosis code for environmental hyperthermia of newborn. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 794. Coders also document this condition as hyperthermia. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified perinatal conditions.

Code Identity

ICD-10-CM Code
P81.0
Billable Status
Yes — Valid for Submission
Code Describes
Environmental hyperthermia of newborn
Short Description
Environmental hyperthermia of newborn
Same as the full description in the CMS dataset.
Parent Code
P81
Other disturbances of temperature regulation of newborn

Code Classification

ChapterP00–P96Certain conditions originating in the perinatal period
SectionP80-P83Conditions involving the integument and temperature regulation of newborn
CategoryP81Other disturbances of temperature regulation of newborn
This CodeP81.0Environmental hyperthermia of newborn

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Hyperthermia
  • Neonatal environmental hyperthermia
  • Neonatal hyperthermia

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to P81.0: its own notes plus those printed at Chapter 16. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Chapter 16 (P00-P96) Certain conditions originating in the perinatal period applies to 463 codes
  • conditions that have their origin in the fetal or perinatal period (before birth through the first 28 days after birth) even if morbidity occurs later

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 16 (P00-P96) Certain conditions originating in the perinatal period applies to 463 codes
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • tetanus neonatorum (A33)

Notes

General instructions on how these codes are used.

From Chapter 16 (P00-P96) Certain conditions originating in the perinatal period applies to 463 codes
  • Codes from this chapter are for use on newborn records only, never on maternal records

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR PNL013
Other specified and unspecified perinatal conditions
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Uncommon Infant and Newborn Problems

It can be scary when your baby is sick, especially when it is not an everyday problem like a cold or a fever. You may not know whether the problem is serious or how to treat it. If you have concerns about your baby's health, call your health care provider right away.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert P81.0 to ICD-9-CMHistory

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

ICD-9-CM
778.4 NB temp regulat dis NEC
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About P81.0Overview

What is the ICD-10 code for environmental hyperthermia of newborn?

The ICD-10-CM code for environmental hyperthermia of newborn is P81.0 (sometimes written as P810). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is P81.0 (Other disturbances of temperature regulation of newborn) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report environmental hyperthermia of newborn on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does P81.0 group to?

When environmental hyperthermia of newborn is the principal diagnosis on an inpatient stay, it groups to MS-DRG 794 (neonate with Other Significant Problems), which carries a relative weight of 1.4934. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of P81.0?

Under the General Equivalence Mappings, environmental hyperthermia of newborn converts to ICD-9-CM 778.4 (NB temp regulat dis NEC). The mapping is approximate, so confirm the match fits the documentation.