Can Mathematical Models of Body Heat Exchanges Accurately Predict Thermal Stress in Premature Neonates?

Abstract

Mathematical models of body heat exchanges can be used to define the thermal limits needed to protect premature neonates nursed in incubators against thermal stress–stress that can have potentially devastating impairments on neurological development and body growth. Predictive models can help caregivers to keep a neonate’s body temperature within the normal range and to solve problems that arise during intensive care, such as the risk of hyperthermia during phototherapy, the risk of hypothermia during transport from one clinical centre to another, and the use of a plastic bag to reduce skin water loss and body dehydration. Here, we review the strengths and limitations of models used to predict the risk of thermal stress, with a focus on uncertainties in the algorithms governing heat transfers between the neonate’s skin and the complicated thermal environment encountered in incubators. We describe attempts to reduce the large number of empirical assumptions and uncertainties in this field, and suggest ways of more accurately modelling optimal thermal conditions for neonates nursed in closed incubators.

Determining the temperature ratings of infant bedding

“…It can be applied to infants because L R is not affected by the size and shape of the body. i m was set as 0.3 based on Schlabach et al (2018)'s study, and w is skin wettedness of infants, set as 0.08 (Delanaud et al, 2019). p sk , p a and p ex are the water vapor pressure of infant skin, ambient air and exhaled air, which can be substituted using t sk and t a according to Antoine equation.…”

“…i m was set as 0.3 based on Schlabach et al. (2018)’s study, and w is skin wettedness of infants, set as 0.08 (Delanaud et al. , 2019).…”

“…, 2019). Their thinner skin may also result in larger trans-epidermal water loss compared with adults (Delanaud et al. , 2019).…”

“…Infants characteristically heat up easily in hot environments and cool easily in cold environments (Kurazumi et al, 2019). Their thinner skin may also result in larger transepidermal water loss compared with adults (Delanaud et al, 2019). Moreover, infants were found to have a higher breathing rate than adults.…”

Thermal Control of the New-borns Using a Cascade Approach

“…However, humidity has not been considered. There are also other interesting works on the modelling of new-born incubators that have been developed in the literature such as that proposed by Delanaud et al (2019). This work's objective is to present a new control structure for an incubator system.…”