The preterm neonate has a higher respiratory rate than a full-term neonate or older child. This causes the rate for evaporative heat loss to be higher due to the movement of air across the mucous membranes in the respiratory tract. Neonates in general are obligatory nose breathers and have an increased head size in comparison to the body, but this does not cause increased evaporative heat loss via the respiratory tract. Increased dead space in the distal airways might occur to due to minimal alveoli formation in the extremely premature infant, but this does not lead to increased evaporative heat loss via the respiratory tract.