Contemporary Challenges in Thermal Homeostasis: Time for a Rethink?

Area of Science:

• Neonatal intensive care
• Thermal physiology
• Infant homeostasis

Background:

• Modern neonatal intensive care includes extremely preterm infants with immature skin and limited thermoregulation.
• Incubator technology has advanced, creating complex thermal environments with servo-control and high humidity.
• Infants often require prolonged support with heated respiratory circuits, adding thermal complexity.

Purpose of the Study:

• To re-evaluate neonatal thermal care strategies in light of contemporary infant physiology and technology.
• To highlight the significant impact of evaporative heat loss on thermal balance in vulnerable neonates.
• To propose evidence-based strategies for improved thermal management in neonatal intensive care.

Main Methods:

• Analysis of thermal balance factors in contemporary neonatal intensive care settings.
• Review of evaporative heat loss mechanisms, particularly transepidermal water loss (TEWL).
• Consideration of environmental factors like humidity, vapour pressure gradients, and dew point.

Main Results:

• Evaporative heat loss via TEWL can equal or exceed metabolic heat production in very preterm infants.
• High relative humidity reduces evaporative stress but increases condensation risks.
• Convective and conductive losses, along with ventilator circuit effects, add thermal instability.

Conclusions:

• Neonatal thermal care should actively manage thermal and vapour gradients, not just core temperature.
• Key strategies include high initial humidity, minimizing incubator openings, pre-warming surfaces, and monitoring dew point.
• Further research is needed on optimal humidity protocols, circuit thermal load, and integrated monitoring systems.