Peripheral temperature measurements from which site provide additional information about the infant's thermal state when graphed with core temperature?

• A. Abdominal surface
• B. Palmar surface
• C. Sole of the foot
• D. Plantar surface

Answer: (C)

In neonatal thermoregulation, core temperature reflects central heat, while a peripheral skin site shows how well heat is being delivered to or lost at the body's surface. The sole of the foot is a convenient distal peripheral site that readily reflects peripheral perfusion. When you graph a peripheral temperature from the foot against core temperature, you can see whether perfusion is adequate or if vasoconstriction is occurring due to cold stress. A cooler sole with a normal core suggests peripheral heat loss, whereas a peripheral temperature that tracks the core indicates better perfusion. Abdominal skin temperature is more central and may not reveal this peripheral-perfusion gradient as clearly, making the foot a better source for additional information.