12 - Bradycardia: heart rate was slow when < 50 beats / minute in the initial frequency with 60 - 100 beats / minute or heart rate droped of more than 20% of the initial frequency = 50 - 59 beats / minute. - Onset time of sedation was defined as the time from the end of local anesthetic administration until patient had OAA / S = 4 score and recorded the sedative level, unit in minutes.