Protective Effects of Sevoflurane Against Lung Ischemia-reperfusion Injury in Rabbits

Objective To investigate the protective effects and possible mechanisms of sevoflurane against ischemia-reperfusion(I/R) injury on the lungs in rabbits.Methods Ninety six Japanese long-ear white rabbits weighting 2.5-3.0 kg were randomly divided into four groups(n=24 each) : sham operation group(S);I/R group in which hilum of left lung was clamped for 45 min and then unclamped for reper-fusion 120 min;Sev-I/R group 1MAC sevoflurane was inhaled for 30 min before ischemia,Sev-S group 1MAC sevoflurane was inhaled for 30 min without I/R.The changes of arterial blood gas analysis,the lung wet-to-dry weight ratio(W/D),The tumor necrosis factorα(TNF-α),interleukin-1β(IL-1β),interleukin-10(IL-10),myeloperoxidase of lung were studied at 45 min after pulmonary ischemia and 60,120 min of reperfusion.The cell counts,percentage of PMN,the lung permeability index and light and electron microscopic examination in left bronchoalveolar lavage fluid(BALF) were performed at 120 of reperfusion.Results During reperfusion,The lung W/D,the levels of TNFα and IL-1β and myeloperoxidase in group IR and group Sev-IR were increased progressively and significantly higher than those in group S,but compared with group IR,pre-administration of sevoflurane could inhibite the increases of index above-mentioned after 120 min of reperfusion(P0.05).Lung permeability index significantly increased in group IR and Sev-IR more than that in group S at 120 min of reperfusion(P0.01),but the degree of increase in lung permeability index of group Sev-IR was decreased markedly compared with of group IR(P0.05).IL-10 content of lung significantly decreased in group IR and group Sev-IR than that in group S,but the IL-10 content of group Sev-IR was increased markedly compared with that of group IR.Histological examination showed that the IR induced lung injury was also ameliorated by sevoflurane pretreatment.Conclusion Inhalation of sevoflurane before ischemia could protect the lung against IR injury in rabbits through an inhibition of PMN infiltration and the release of TNFα and L-1β,and an increase in the expression of IL-10.