Figure 55-2 Impact of halothane, enflurane, isoflurane, and sevoflurane at 1.5 and 2.0 minimum alveolar concentration (MAC) on hepatic arterial oxygen delivery in chronically instrumented dogs. Halothane produced the greatest reduction in hepatic arterial oxygen delivery, whereas sevoflurane and isoflurane had insignificant effects on oxygen delivery at any MAC level. *Differs from isoflurane and sevoflurane at comparable MAC values (P < .05). †Differs from sevoflurane at comparable MAC values (P < .05). (Data from Frink EJ, Morgan SE, Coetzee A, et al: The effects of sevoflurane, halothane, enflurane, and isoflurane on hepatic blood flow and oxygenation in chronically instrumented greyhound dogs. Anesthesiology 76:85–90, 1992.)