Background: Isoflurane is a volatile anaesthetic that has been commonly used since 1980. The major metabolites of isoflurane are fluoride ion and trifluoroacetate, both excreted in the urine.
Aim: This study manage to show the histopathological findings of ingested isoflurane on liver, kidney and lugs in an animal model. Twenty-one rabbits were selected and divided into three groups: Group Isoflurane-5 (I-5); Group Isoflurane-10 (I-10); and Group Control (C). Each group consisted of seven rabbits. I-5 and I-10 received 5 ml/kg and 10 ml/kg of liquid isoflurane, respectively, via nasogastric tube, while C received 5 ml/kg saline (0.9% NaCI). All animals in I-5 and I-10 were sacrificed without anesthetic drug administration. Tissue samples from livers, kidneys and lungs were collected, preserving tissue unity and avoiding infliction of any trauma. Samples were fixed in 10% formalin solution, embedded in paraffin blocks and sliced into 5 μm sections. To investigate the effects of isoflurane, sections were examined under light microscope and histopathological changes were scored.
Results: Mean injury scores and the appearance of portal lymphocyte infiltration in liver samples showed significant increases in I-5 and I-10 compared to C (p = 0.005, p = 0.001 and p = 0.001, respectively). Mean lung injury scores revealed significant increases after isoflurane treatment in I-5 and I-10 compared to C (p = 0.026 and p = 0.017, respectively).
Conclusions: Ingested isoflurane led to mild liver and lung injuries in rabbits.