Isoflurane-sevoflurane administration before ischemia attenuates ischemia-reperfusion-induced injury in isolated rat lungs

Background: The effects of volatile anesthetics on ischemia-reperfusion (IR )-induced lung injury are not clear. The authors investigated the effects o f preadministration of isoflurane and sevoflurane on IR-induced lung injury in an isolated buffer-perfused rat lung model. Methods: Isolated rat lungs were designated into four groups: control group (n = 6): perfusion for 120 min without ischemia; IR group (n = 6): interru ption of perfusion and ventilation for 60 min followed by reperfusion for 6 0 min; sevoflurane (SEVO)-IR (n = 6) and isoflurane (ISO)-IR (n = 6) groups : 1 minimum alveolar concentration (MAC) isoflurane or sevoflurane was admi nistered for 30 min, followed by 60 min ischemia, then 60 min reperfusion. The authors measured the coefficient of filtration (Kfc) of the lung, lacta te dehydrogenase (LDH) activity, tumor necrosis factor alpha, and nitric ox ide metabolites (nitrite + nitrate) in the perfusate and the met-to-dry lun g weight ratio. Results: IR caused significant increases in the coefficient of filtration ( approximately sevenfold at 60 min of reperfusion compared with baseline; P < 0.01), the wet-to-dry lung weight ratio, the rate of increase of lactate dehydrogenase activity, and tumor necrosis factor or in the perfusate, and caused a significant decrease in nitric oxide metabolites in the perfusate, Administration of 1 MAC isoflurane or sevoflurane before ischemia signific antly attenuated IR-induced increases in the coefficient of filtration and the wet-to-dry lung weight ratio, inhibited increases in the rate of increa se of lactate dehydrogenase activity and tumor necrosis factor CY in the pe rfusate, and abrogated the decrease in nitric oxide metabolites in the perf usate. No difference was found between the SEVO-IR and ISO-IR groups. Conclusion: Isoflurane and sevoflurane administered before ischemia can att enuate IR-induced injury in isolated rat lungs.