Emergency Management of Neonatal Hyperthermia
Immediately remove all excessive clothing, blankets, and warming devices, and place the neonate in a room temperature environment (23-25°C) while simultaneously evaluating for serious bacterial infection and other life-threatening causes. 1
Immediate Temperature Control Measures
Active cooling interventions:
- Remove all excessive clothing, blankets, and any thermal mattresses or warming devices immediately 1
- Place the infant in a room with appropriate ambient temperature of 23-25°C 1
- Turn off radiant warmers if in use 2
- Allow passive cooling to normothermia (36.5-37.5°C) through environmental adjustment 3
Critical caveat: Hyperthermia (>38.0°C) is associated with increased mortality, neonatal seizures, and adverse neurologic outcomes including encephalopathy, and must be avoided 2, 1. The American College of Cardiology explicitly states that hyperthermia carries potential associated risks that warrant aggressive intervention 1.
Simultaneous Diagnostic Evaluation
Assess for serious bacterial infection (SBI):
- Neonates with temperature instability have substantial risk for SBI or other significant pathology 4
- Obtain rectal temperature for accurate core measurement (≥38.0°C defines fever in neonates) 3, 5
- Monitor for signs of serious illness: poor feeding, decreased activity, difficulty breathing, ill appearance 1
Evaluate for other causes of hyperthermia:
- Maternal fever during labor (associated with perinatal respiratory depression, neonatal seizures, cerebral palsy) 2
- Iatrogenic overheating from excessive warming interventions during resuscitation or transport 6
- Environmental overheating from excessive bundling or room temperature 1
- Rare metabolic or endocrine emergencies 7
Monitoring During Cooling
Temperature monitoring protocol:
- Continuous axillary temperature monitoring as infant cools toward normothermia (36.5-37.5°C) 3
- Avoid rapid cooling; gradual passive cooling through environmental adjustment is preferred 1
- Target normothermia range of 36.5-37.5°C 3
Clinical monitoring:
- Assess for signs of serious infection or deterioration 4
- Monitor vital signs, perfusion, and neurologic status 1
- Watch for complications associated with temperature instability 2
Common Pitfalls to Avoid
Do not use active cooling methods (ice packs, cold water immersion) in neonates: These aggressive cooling techniques are appropriate for adult heat stroke 7 but are not indicated for neonatal hyperthermia, which typically responds to passive environmental cooling 1.
Do not dismiss hyperthermia as benign: Even in the absence of obvious infection, hyperthermia in neonates warrants full evaluation, as 7.9% of hypothermic neonates and a similar proportion of hyperthermic neonates have serious bacterial infections 4.
Do not continue warming interventions: Thermal mattresses and excessive warming devices increase hyperthermia risk and should be discontinued immediately 1, 6. The shift from hypothermia prevention to hyperthermia has been documented in transport studies, with hyperthermia rates increasing from 4% to 19% over time due to overzealous warming 6.
Disposition and Follow-up
Admission criteria: