Abstract:Objective To observe the effects of dexmedetomidine on cerebral oxygen metabolism, serum dynorphin A_1-13 (DynA_1-13) and neuron-specific enolase (NSE) levels in elderly patients undergoing hepatic carcinectomy. Methods A total of 120 elderly patients with hepatocellular carcinoma receiving scheduled hepatectomy from June 2017 to April 2019 were randomly divided into study group and control group (n=60, each). The combined intravenous-inhalation general anesthesia was performed in both groups. At 15 minutes before induction of anesthesia, the loading dose of dexmedetomidine (1.0 μg/kg) was given by micro pump injection intravenously and continuously at the speed of 0.2-0.5 μg·kg^-1·h^-1 until 30 mins before the end of operation in study group, and the same amount of normal saline was given in control group by the same method. The following data were compared between the two groups before anesthesia (T₀), during tracheal intubation (T₁), at skin incision (T₂), and at the end of operation (T₃):hemodynamic indexes ［mean arterial pressure (MAP), heart rate (HR)］, cerebral extraction of oxygen(CERO₂), arterial-jugular venous oxygen content differences (Da-jvO₂), serum DynA_1-13, NSE levels. The cognitive function (MMSE score) of two groups were compared before operation, 3- and 7- day after operation. The incidence of adverse reactions and cognitive impairment 1 week after operation were also observed in two groups. Results There were no significant differences in MAP and HR between T₁, T₂, T₃ and T₀ in study group (P>0.05), and MAP and HR were statistically lower in study group than those in control group at T₁, T₂ and T₃ (P<0.05); the levels of CERO₂ and Da-jvO₂ at T₁, T₂ and T₃ were lower than those at T₀ in two groups and were statistically lower in study group than those in control group (P<0.05, P<0.01); the levels of DynA_1-13 and NSE at T₁, T₂ and T₃ were higher than those at T₀ in two groups, however, they were lower in study group than those in control group(P<0.05, P<0.01). At 3 and 7 days after operation, MMSE scores were lower than those before operation in two groups, but they were higher in study group than those in control group (P< 0.05, P<0.01). The incidences of adverse reactions and cognitive impairment were 11.67% and 10.00% respectively in study group and were significantly lower than those (28.33%, 25.00%, respectively) in control group(P<0.05). Conclusion In elderly patients undergoing hepatectomy for hepatocellular carcinoma, dextrometridine can stabilize hemodynamics, improve cerebral oxygen metabolism and reduce serum DynA_1-13 and NSE levels, and reduce cognitive impairment, and has high safety.