Index of potency of general anesthesia: (A) Minimum alveolar concentration, (B) Diffusion coefficient, (C) Dead space concentration, (D) Alveolar blood concentration
Answer is A. Minimal alveolar concentrationIt is the lowest concentration of the anaesthetic in pulmonary alveoli needed to produce immobility in response to a painful stimulus (surgical incision) in 50% individualsIt is the measure of potency of inhalation Gas.(Refer: Morgan and Mikhail's Clinical Anaesthesiology, 5th edition, pg no. 162 - 163)