<prompt> Potency of inhalational anesthetic agent is measured by-Minimum alveolar concentrationDiffusion coefficientDead space concentrationAlveolar blood concentration  <response>: Ans. is a i.e., Minimum alveolar concentration o Minimum alveolar concentration MAC Oil: gas partition cofficient lipid solubility - Measure of Potencyo Blood : gas partition coefficient - measure blood solubility and speed of induction recovery.Minimal alveolar concentration MACo Most important measure of potency is minimal alveolar concentration MAC. MAC is the lowest concentration of the anaesthetic in pulmonary alveoli needed to produce immobility in response to a painful stimulus surgical incision in 50 individuals. Higher the MAC, less potent the anaesthetic agent.o Methoxyflurane has minimum MAC 0.16. The most potent inhalational agent.o N2O has maximum MAC 105. The least potent inhalational agent.o Order of potency in decreasing order MAC in increasing order:Methoxyflurane MAC 0.16 Trilene MAC 0.2 Halothane MAC 0.74 Chloroform MAC 0.8 Isoflurane MAC 1.15 Enflurane MAC 1.68 Ether MAC 1.92 Sevoflurane MAC 2.0 Desflurane MAC 6.0 Cyclopropane MAC 9.2 N2O MAC 104. 