Sedative effect analysis of dexmedetomidine administered at different infusing rates in senile cataract patients with retrobulbar nerve block / 中国医师进修杂志

ABSTRACT

Objective To observe the sedative effect of dexmedetomidine administered at different infusing rates in senile cataract patients with retrobulbar nerve block.Methods Eighty-four senile cataract patients with retrobulbar nerve block were divided into Ⅰ,Ⅱ and Ⅲ group by random systematic sampling method with 28 cases each,the dexmedetomidine infusing rates were 0.2,0.4 and 0.6 μg/(kg·h) accordingly.Ramsay score and mean arterial pressure (MAP),heart rate (HR),respiratory rate (RR),pulse oxygen saturation (SpO2) were recorded before anesthesia (T0),after retrobulbar nerve block (T1),and 1 0,20,30,60min after sedative administration (T2-T5).Results Ramsay scores were higher in three groups at T2-T5 than that at T0 [Ⅰ group(2.6 ± 0.7),(2.5 ± 0.2),(2.4 ± 0.8),(2.4 ± 0.3) scores vs.(2.0 ± 0.0) scores,Ⅱ group(3.0 ± 0.7),(3.8 ± 0.7),(4.2 ± 0.2),(4.5 ± 0.2) scores vs.(2.0 ± 0.0) scores,Ⅲ group(3.8 ±0.6),(4.7 ± 0.4),(5.2 ± 0.8),(5.6 ± 0.6) scores vs.(2.0 ± 0.0) scores],Ⅲ group was higher than Ⅰ group and Ⅱ group,Ⅱ group was higher than Ⅰ groupatT3-T5,difference was statistically significant (P＜0.05).HR was slower in three groups at T3-T5 than that at T0 (P ＜ 0.05),Ⅲ group was slower than Ⅰgroup and Ⅱ group,difference was statistically significant (P＜0.05).There were no significant changes in MAP,RR and SpO2 among groups and the group (P ＞ 0.05).Conclusion Bolus infusion dexmedetomidine 0.5 μ g/kg followed by intravenous infusion at 0.2-0.4 μ g/ (kg· h) is suitable for sedation of senile patients with cataract surgery.