What is the immediate management for newborn cold stress?

Immediate Management of Newborn Cold Stress

Begin active rewarming immediately using a radiant warmer or servo-controlled incubator, targeting normothermia (36.5-37.5°C), while simultaneously checking blood glucose and monitoring temperature every 15-30 minutes to prevent iatrogenic hyperthermia. 1

Immediate Interventions

Temperature Restoration

• Place the infant under a radiant warmer or in a servo-controlled incubator immediately without delay for diagnostic workup 1
• Set the warmer to achieve normothermia (36.5-37.5°C core temperature) 1
• Both rapid (≥0.5°C/hour) and slow (<0.5°C/hour) rewarming rates are acceptable, though continuous monitoring is essential regardless of rate chosen 1

Critical Concurrent Assessment

• Check blood glucose immediately as hypothermia is strongly associated with hypoglycemia in infants 1, 2
• Treat hypoglycemia promptly with intravenous glucose infusion if present 2
• Monitor temperature continuously or every 15-30 minutes during rewarming 1

Gestational Age-Specific Approaches

Preterm Infants (<34 weeks gestation)

For preterm infants, use plastic bag or wrap (without drying) combined with a head covering as the foundation of thermal management. 3

• Plastic wrap/bag: Place infant in polyethylene bag up to the neck immediately without drying—this has high-certainty evidence showing improved survival (NNT=24) and reduced hypothermia (NNT=3) 3
• Head covering: Add a plastic cap, which dramatically increases normothermia rates (NNT=2) 3
• Environmental temperature: Maintain delivery room/resuscitation area at ≥23°C (ideally 23-25°C) 3
• Thermal mattress: Consider adding if hypothermia persists, but monitor closely as this increases hyperthermia risk (NNH=30 when combined with plastic wrap) 3
• Heated humidified gases: Use for respiratory support if available and admission hypothermia is a documented problem 3

Term and Late Preterm Infants (≥34 weeks gestation)

• Use radiant warmer with servo control set to 36.5-37.0°C 1
• Avoid thermal mattresses in term infants as they significantly increase hyperthermia risk 1
• Skin-to-skin care is beneficial for maintaining temperature when other resources are limited 3
• Ensure room temperature ≥23°C 3

Critical Monitoring During Rewarming

Temperature Surveillance

• Monitor core temperature (axillary or rectal) every 15-30 minutes until stable normothermia achieved 1
• Check peripheral extremity temperatures by hand-touch to detect ongoing cold stress before hypothermia recurs 4, 5
• Stop active warming when core temperature reaches 36.5°C to prevent overshoot hyperthermia 1

Hyperthermia Prevention

Avoiding hyperthermia (>38.0°C) during rewarming is critical as it increases mortality, seizures, and neurologic injury. 3, 1

• Never use excessively high warmer settings 1
• Transition to servo-controlled mode rather than manual high settings 1
• The combination of multiple warming devices (plastic wrap + thermal mattress) increases hyperthermia risk 3.67-fold 3

Metabolic Monitoring

• Continue glucose monitoring throughout rewarming period 1, 2
• Assess feeding tolerance and activity level as indicators of successful rewarming 1

Common Pitfalls to Avoid

• Never delay rewarming to investigate the cause of hypothermia—begin warming immediately 1
• Do not use thermal mattresses in term infants 1
• Avoid unmonitored rewarming, which carries significant overshoot hyperthermia risk 1
• Do not rely solely on core temperature measurement—cold extremities indicate ongoing cold stress even with normal core temperature 6, 4, 5
• In preterm infants <34 weeks, do not dry the infant before placing in plastic wrap, as this defeats the purpose of reducing evaporative heat loss 3

Recognition of Cold Stress vs. Hypothermia

Cold stress occurs before hypothermia develops and can be detected by cold extremities (hands/feet) even when core temperature remains normal. 6, 4, 5

• Cold stress represents increased metabolic demand to maintain normal core temperature in a sub-thermoneutral environment 4
• A >2°C difference between core and peripheral skin temperature indicates cold stress 5
• Early intervention during cold stress prevents progression to hypothermia with its associated morbidity and mortality 6, 4, 7