The relationship between postnatal skin maturation and electrical skin impedance

Electrical impedance, which is the resistance to an alternating current, is a parameter that is used to determine the condition of the electrode-skin interface before evoked potentials are recorded. High electrical impedance can result in inaccurate interpretation of evoked potentials due to excessive artifacts. This study investigated the electrical skin impedance in 36 full-term infants who ranged from 0 to 1 year of age to delineate the temporal relationship between skin maturation and skin impedance. Correlation and regression analyses demonstrated a statistically significant inverse relationship between electrical skin impedance and age during the first year of life. This drop in skin impedance during the first few postnatal months was attributed to an increase in skin hydration as a result of the greater functional maturity of eccrine sweat glands.