2027 ICD-10-CM Diagnosis Code P81.9Disturbance of temperature regulation of newborn, unspecified
ICD-10-CM Codes›P00–P96›P80-P83›P81
- Billable — Valid for Submission
- Not Chronic
P81.9 is a billable ICD-10-CM diagnosis code for disturbance of temperature regulation of newborn, unspecified. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 794. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified perinatal conditions.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Acute rise of fever
- Biphasic fever
- Body temperature above reference range
- Central fever
- Chill
- Continuous fever
- Disorder characterized by fever
- Falling phase of fever
- Febrile leukopenia
- Feeling feverish
- Fever
- Fever defervescence
- Fever due to infection
- Fever greater than 100.4 Fahrenheit
- Fever of newborn
- Fever with chills
- Fever, diurnal variation
- Feverish cold
- Gradual fall of fever
- Gradual rise of fever
- Hyperthermia
- Increased skin temperature
- Intermittent fever
- Irregular fever
- Low grade pyrexia
- Myoclonus associated with fever
- Neonatal disturbance of temperature regulation
- Neonatal hyperthermia
- Neurogenic hyperthermia
- Perinatal disorder of skin and temperature regulation
- Phase of fever - finding
- Plateau phase of fever
- Prolonged fever
- Pyrexia of unknown origin
- Pyrexia of unknown origin co-occurrent with human immunodeficiency virus infection
- Rapid fall of fever
- Remittent fever
- Reversed diurnal fever
- Rising phase of fever
- Severe fever with thrombocytopenia syndrome
- Shivering or rigors
- Slightly remittent fever
- Staircase fever
- Sweating fever
- Viral fever
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to P81.9: 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.
- 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
Applicable To
Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.
- Fever of newborn NOS
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.
Notes
General instructions on how these codes are used.
- 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.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name P81.9, its category, or a range that includes it.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Disorder (of) See Also: Disease;
Disturbance (s) See Also: Disease;
Hyperthermia (of unknown origin) See Also: Hyperpyrexia;
newborn P81.9
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
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 P81.9 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About P81.9Overview
What is the ICD-10 code for disturbance of temperature regulation of newborn, unspecified?
The ICD-10-CM code for disturbance of temperature regulation of newborn, unspecified is P81.9 (sometimes written as P819). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is P81.9 (Other disturbances of temperature regulation of newborn) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report disturbance of temperature regulation of newborn, unspecified on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does P81.9 group to?
When disturbance of temperature regulation of newborn, unspecified 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 P81.9?
Under the General Equivalence Mappings, disturbance of temperature regulation of newborn, unspecified converts to ICD-9-CM 778.4 (NB temp regulat dis NEC). The mapping is approximate, so confirm the match fits the documentation.
