METHODS Sixty-four patients were included in this study. They were randomised into Group A(atropine 0.5mg, n=32) and Group S(saline 0.9%, n=32), immediately before pre-administration of remifentanil. The primary outcome was the time to tracheal intubation and the secondary outcomes were rocuronium onset time, time to loss of consciousness(LOC), time to reach a value of 60 on the bispectral index(BIS), and haemodynamic variables.
RESULTS The median[Interquartile range] of the time to tracheal intubation was 240[214, 288]s in Group S and 190[176, 212]s in Group A(median difference: 50s, 95% confidence interval: 27-80s, P=0.001). Rocuronium onset time was significantly decreased in Group A compared to that in Group S(129[110, 156]vs. 172[154, 200], P=0.001). The times to LOC and reach 60 on the BIS were not significantly different between the two groups. Cardiac output(CO) and heart rate were less decreased in Group A than in Group S(P=0.02, P<0.001, respectively).
CONCLUSIONS Prophylactic administration of atropine could compensate for the reduction in CO in cases pre-administered with remifentanil in target-controlled propofol and remifentanil anaesthesia. This in turn prevented prolongation of rocuronium onset time and reduced the time to tracheal intubation.