Abstract: Objective: To compare the effect of co-induction with different triple anesthetics in blunting the cardiovascular responses to tracheal intubation.Methods: Sixty patients were randomly divided into three groups and induced with thiopental,proplfol or etornidate in combination with midazolam and fentanyl respectively.Blood pressure(BP) and heart rate(HR) were observed before and after fracheal intubation.Results: At tracheal intubation,HR in thiopental group was a little higher than the baseline(P>0.05),but in propofol and etomidate groups,the changes were not significant.BP in propofol group was markedly lower than the baseline(P<0.05),but in thiopental and etomidate groups,the changes were not significant.Before and after tracheal intubation,the occurrence of hypotension and bradycardia in propofol group was slightly higher than that in thlopental group,but there was no occurrence of hypotension in etomidate group.Conclusions: Coinduction with triple anesthetics proves to be effective in blunting the cardiovascular responses to tracheal intubation.Proplfol can completely eliminate the cardiovascular responses to tracheal intubation,but facilitate hypotension and bradycardia;thiopenlal and etomidate can only eliminate the increase of BP and HR respectively.