Objective To establish a HS-GC test method for the determination of enflurane,isoflurane,diflurane,sevoflurane and its metabolite hexafluoroisopropanol(HFIP)in blood,and to establish a LC-MS/MS method for the determination of trifluoroacetic acid(TFA),the co-metabolite of enflurane,isoflurane,and deflurane in blood.Methods Place 0.5 mL blood sample in a 10 mL headspace bottle,add 1.0 mL ultrapure water to mix,then add 0.5 mL n-butanol internal standard solution,sealed and heated at 70℃for 20 min,take the upper layer of gas for HS-GC analysis,qualitatived by dual-column retention time and quantified by the internal standard curve;Blood sample was acetonitrile precipitated protein,separated by liquid chromatography,scanned with electrospray ionization(ESI),negative ion mode,and examined in multiple reaction monitoring mode(MRM),qualitatived by retention time and characteristic ions,quantified by standard curve.Results The detection limits(LOD)of enflurane,isoflurane,desflurane,heptaflurane,HFIP and TFA are 0.05,0.2,0.5,0.05,0.5 μg/mL and 0.5 ng/mL,and linear range as 1～100 μg/mL(TFA:1～100 ng/mL),with correlation coefficients greater than 0.999.The extraction recovery rate is between 30%and 80%,and the intra-day and inter-day precision are less than 5%.The accuracy is between 85%and 115%.Conclusion This method is quick and simple,and can be used for qualitative and quantitative analysis of enflurane,isoflurane,desflurane,sevoflurane and their metabolites in blood.