Application of dexmedetomidine combined with local anesthesia in ophthalmic surgery

Objective To evaluate the efficacy and security of different doses of dexmedetomidine on patients undergoing ophthalmic surgery with local anesthesia.Methods Sixty patients with ocular trauma surgery were randomly divided into three groups (20 cases in each group).Dexmedetomidine in group B and C were administrated with micro-pumps in a loading dose of 0.5 μg/kg over 10 mins,and at the same time,the same amount of normal saline was pumped in the same way in group A.Then dexmedetomidine was pumped as 0.3 μg/kg/h in group B and 0.6 μg/kg/h in group C,and normal saline was maintained in group A until the end of surgery.The Ramsay sedation score,systolic blood pressure(SBP),diastolic blood pressure(DBP),heart rate(HR),pulse oxygen saturation (SpO2) of the three groups were recorded.The time-points included before the administration(T0),the end of load measurement(T1),30 min after administration(T2),60 min after administration(T3) and the end of operation(T4).Results There were no significant differences in age,height,weight,operation time and SpO2 at each time point among the three groups.Compared with group A,Ramsay sedation score in group B and group C were significantly higher in T2-T4 time points,and the difference had statistical significance.Compared with To,the SBP,DBP and HR of group A were much higher in T1-T4,and the difference was statistically significant.The SBP decreased in T3-T4 of group B and T2-T4 of group C.The HR of group B and C decreased in T1-T4,and the difference was statistically significant.Conclusion Dexmedetomidine combined with local anesthesia can provide good sedation in ophthalmic surgery with a loading dose of 0.5 μg/kg and maintenance dose of 0.3 μg/kg. Key words: Dexmedetomidine ;  Anesthesia ;  Surgery, ophthalmic