The anesthetics halothane, enflurane, isoflurane and 2,6-diisopropylphenol negatively affect several energy-linked processes in isolated rat liver mitochondria, decreasing their efficiency. The adverse effects observed in the presence of halothane, enflurane and 2,6-diisopropylphenol are similar for many aspects although, being caused by anesthetics having different molecular structures, they differ significantly from the quantitative point of view. A relevant role in the anesthetic-induced mitochondrial injuries appears to be played by long-chain acylCoA, whose level is markedly increased in mitochondria incubated in the presence of halogenated anesthetics. In addition, the amount of intramitochondrial calcium may also influence the severity of these injuries.