Abstract： Objective:To investigate the effects of prior-to-induction infusion vs whole-process infusion of dexmedetomidine (DEX) on hemodynamics of patients.Methods:Ninety patients, who underwent elective surgery under general anesthesia with tracheal intubation at Guangzhou Medical University Hospital of Traditional Chinese Medicine between December 2019 and June 2020, were included as subjects and were randomly divided into the blank control group (given intravenous infusion of normal saline at a background dose of 0.5 μg/kg for 10 min prior to induction, followed by a dose of 0.5 μg·kg -1·h -1 until the end of the operation) , the study group (given pumping of DEX 0.5 μg/kg for 10 min prior to induction, followed by drug discontinuation) , and whole-process infusion group (given pumping of DEX 0.5 μg/kg for 10 min prior to induction, followed by DEX infusion at a dose of 0.5 μg·kg -1·h -1until the end of the operation) . At various time points, ie. Before DEX use (T0) , completion of intravenous DEX bolus (T1) , before endotracheal intubation (T2) , immediately after intubation (T3) , 5 min after intubation (T4) , 10 min after intubation (T5) , at skin incision (T6) , 15 min after skin incision (T7) , 30 min after skin incision (T8) , 45 min after skin incision (T9) , 60 min after skin incision (T10) , 75 min after skin incision (T11) and 90 min after skin incision (T12) , the three groups were observed for hemodynamic indicators, including systolic blood pressure (SBP) , mean arterial pressure (MAP) , diastolic blood pressure (DBP) , and heart rate (HR) . Adverse reactions in the three groups were also recorded. Results:Compared with the baseline data at T0, hemodynamic fluctuations were seen in all groups at T3 and T6, with greatest excursion in the blank control group and minimal changes in the study group ( P<0.05) . At T7 through T12, the whole-process infusion group showed a large excursion in hemodynamic fluctuations, which was most prominent at T12; the study group showed milder fluctuations at these time points ( P<0.05) . The incidence of adverse reactions was lower in the study group than that in the other two groups ( P<0.05) . Conclusion:Infusion of DEX prior to induction is conducive for maintenance of hemodynamic stability. In comparison, whole-process intravenous infusion of DEX is readily to cause hemodynamic fluctuations in patients at the end of surgery.