ICD-10-CM Code P81.9

Disturbance of temperature regulation of newborn, unspecified

Version 2020 Billable Code

Valid for Submission

P81.9 is a billable code used to specify a medical diagnosis of disturbance of temperature regulation of newborn, unspecified. The code is valid for the year 2020 for the submission of HIPAA-covered transactions. The ICD-10-CM code P81.9 might also be used to specify conditions or terms like acute rise of fever, biphasic fever, body temperature above reference range, central fever, chill, conditions involving the integument and/or temperature regulation of fetus or newborn, etc

Short Description:Disturbance of temperature regulation of newborn, unsp
Long Description:Disturbance of temperature regulation of newborn, unspecified

Tabular List of Diseases and Injuries

The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code P81.9:

Inclusion Terms

Inclusion Terms
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
  • Fever of newborn NOS

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code P81.9 are found in the index:


The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

  • Acute rise of fever
  • Biphasic fever
  • Body temperature above reference range
  • Central fever
  • Chill
  • Conditions involving the integument AND/OR temperature regulation of fetus OR newborn
  • Continuous fever
  • Disorder characterized by fever
  • Disturbance of temperature regulation of newborn
  • Falling phase of fever
  • Febrile leukopenia
  • Feeling feverish
  • Feels hot/feverish
  • Fever
  • Fever defervescence
  • Fever greater than 100.4 Fahrenheit
  • Fever of the newborn
  • Fever symptoms
  • Fever with chills
  • Fever with infection
  • Fever, diurnal variation
  • Feverish cold
  • Finding of temperature of skin
  • Gradual fall of fever
  • Gradual rise of fever
  • Hyperthermia in newborn
  • Increased skin temperature
  • Intermittent fever
  • Irregular fever
  • Low grade pyrexia
  • Myoclonus associated with fever
  • Neurogenic hyperthermia
  • O/E - character of fever
  • O/E - fever
  • O/E - fever - acute rise
  • O/E - fever - continuous
  • O/E - fever - fast fall-crisis
  • O/E - fever - general
  • O/E - fever - gradual rise
  • O/E - fever - intermittent
  • O/E - fever - irregular
  • O/E - fever - remittent
  • O/E - fever-gradual fall-lysis
  • O/E - pyrexia of unknown origin
  • O/E - staircase fever
  • O/E - temperature elevated
  • Perinatal skin and temperature regulation disorders
  • 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 virus
  • Shivering or rigors
  • Slightly remittent fever
  • Staircase fever
  • Sweating fever
  • Temperature symptoms
  • Temperature symptoms
  • Viral fever
  • Viral fever

Convert P81.9 to ICD-9

  • 778.4 - NB temp regulat dis NEC (Approximate Flag)

Code Classification

  • Certain conditions originating in the perinatal period (P00–P96)
    • Conditions involving the integument and temperature regulation of newborn (P80-P83)
      • Other disturbances of temperature regulation of newborn (P81)

Code History

  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016
    (First year ICD-10-CM implemented into the HIPAA code set)
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020

Information for Patients

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.

Learning information about your baby's condition can help ease your worry. Do not be afraid to ask questions about your baby's care. By working together with your health care provider, you make sure that your baby gets the best care possible.

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