Geriatrics: MAC alterations
Advanced, Clinical Subspecialties
The minimum alveolar concentration (MAC) of inhaled anesthetics decreases with age. For every decade of life after age 20, the MAC is reduced by ~6%. Put another way:
MAC(age adjusted) = (1 - 0.06 * (Age - 20)/10) * MAC(standard)
This reduction in MAC is likely due to changes in neurotransmitter balance and increased cerebral atrophy in the geriatric population.