Thermoregulation in the Newborn

Publication: 01/03/2004  --
Last review: 15/05/2019  
Next review: 15/05/2022  
Clinical Protocol
ID: 342 
Approved By:  
Copyright© Leeds Teaching Hospitals NHS Trust 2019  


This Clinical Protocol is intended for use by healthcare professionals within Leeds unless otherwise stated.
For healthcare professionals in other trusts, please ensure that you consult relevant local and national guidance.

Thermoregulation in the Newborn

Thermoregulation is the ability to balance heat production and heat loss in order to maintain body temperature within a normal range.

Hypothermia and hyperthermia should be avoided as they can result in serious metabolic consequences and increased the risk of morbidity and mortality in the preterm newborn infant. Sustaining normothermia maximises metabolic efficiency, decrease oxygen consumption, enables efficient enzyme function and enables optimal calorie use.

Reference values (AM. AC. Ped) in the neonate are

  • Extreme Hyperthermia >38oC- Danger
  • Mild Hyperthermia 37.2- 38oC- cause for concern
  • Normal Temperature 36’5- 37.2oC
  • Mild Hypothermia 36-36.4oC- Cause for concern
  • Moderate Hypothermia 32-35.9oC- Danger
  • Severe Hypothermia < 32oC- Out look grave

Heat loss through evaporation of water from the immature skin is a major problem in very preterm infant. In this group, a temperature <36’5oC on admission to the neonatal unit is not infrequently observed, especially after (prolonged) resuscitation.

Hypothermia can be avoided by raising the humidity of the air around the preterm infant (plastic bag at delivery/ humidified incubator)

Newborn Infant <=26 weeks Gestational age

  1. Preparation
    • Ensure resuscitaire platform is preheated
    • Prepare clean, non-sterile, transparanet plastic bag for viginal delivery. Request the use of sterile neosave plastic bag for C-section. (Plastic bags available in red emergency trolley or red emergency bags)
  2. At birth
    • Do not dry infant, immediately place body in plastic bag.
    • Place hat on infant’s head
    • Do not cover with blankets, in order to allow heat to reach baby from radiant heater above
  3. Stabilisation process
    • Standard newborn life support if necessary (NLS)
    • Check temperature at 10 minutes of age and assess need for transwarmer mattress. (If required ensure material side of mattress is facing upwards)
    • For UVC: cut small hole in bag, whilst keeping most of the body covered.
  4. Transport to NICU
    • On resuscitaire platform +/- transwarmer.
    • Cover with blankets when on resuscitaire as radiant heater does not work in transit.
  5. In NICU
    • If transwarmer required keep infant on mattress until temperature stable. Note transwarmer mattress cools after 2 hours.
    • Remove plastic bag once humidified atmosphere created
    • Record axillary temperature with skin probe and act accordingly.

Newborn Infant 27-32 weeks gestational age
1-5 as above (unlikely to require transwarmer)

Newborn infant >32 weeks gestational age

  1. Place on preheated resuscitaire platform and dry thoroughly
  2. Remove wet blankets and cover with warm blanket
  3. Place hat on baby’s head
  4. Newborn life support as required (NLS)
  5. Transfer to NICU
  6. Check temperature at 10 minutes or on arrival at NICU if before 10 minutes, and then at 30 minutes later.

If any baby is admitted to the neonatal unit, transitional care or postnatal ward with a temperature < 36.0C then a datix should be completed


Record: 342

See The Policy

Clinical condition:

Hypothermia/ Hyperthermia

Target patient group: Newborn infants
Target professional group(s): Secondary Care Doctors
Secondary Care Nurses
Adapted from:


Evidence base

Not supplied

Document history

LHP version 1.0

Related information

Not supplied

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