不同速率输注右美托咪定在老年白内障手术球后神经阻滞中的镇静效果观察

Sedative effect of dexmedetomidine administered at different infusing rate in senile cataract surgery with retrobulbar nerve block

目的 探讨不同速率输注右美托咪定在老年白内障手术球后神经阻滞中的镇静效应.方法 选择93例65～ 82岁白内障患者,将患者按机械抽样法分为A、B、C三组,每组31例.由术者行球后神经阻滞,阻滞完毕后手术开始前10 min静脉泵入右美托咪定0.5μg/kg,之后A、B、C组分别以0.2、0.4、0.6μg/（kg·h）速率维持.观察并记录三组患者麻醉前（T0）、神经阻滞完毕即刻（T1）及用药后10 min（T2）、20min（T3）、30 min（T4）、60 min（T5）的Ramsay评分和平均动脉压（MAP）、心率、呼吸频率、脉搏血氧饱和度（SpO2）.结果 三组患者均顺利完成手术.三组T2～T5 Ramsay评分均高于本组T0 [A组：（2.6±0.7）、（2.5±0.2）、（2.4±0.8）、（2.4±0.3）分比（2.0±0.0）分;B组：（3.0±0.7）、（3.8±0.7）、（4.2±0.2）、（4.5±0.2）分比（2.0±0.0）分;C组：（3.8±0.6）、（4.7±0.4）、（5.2±0.8）、（5.6±0.6）分比（2.0±0.0）分],C组T3～T5高于A组和B组、B组高于A组,差异均有统计学意义（P＜0.05）.三组T3～T5心率均慢于本组T0[A组：（77±5）、（76±7）、（74±12）次/min比（88±12）次/min;B组：（72±9）、（70±8）、（70±11）次/min比（90±10）次/min;C组：（64±7）、（55±7）、（54±6）次/min比（88±9）次/min],而且C组慢于A组和B组,差异均有统计学意义（P＜0.05）.三组组内和组间MAP、呼吸频率比较差异均无统计学意义（P＞0.05）.三组均未发生呼吸抑制、恶心呕吐、眩晕等并发症.结论 静脉泵入右美托咪定0.5μg/kg后以0.2～0.4μg/（kg·h）维持适合老年白内障手术患者的清醒镇静.

Objective To observe the sedative effect of dexmedetomidine in senile cataract surgery with retrobulbar nerve block.Methods Ninety-three senile cataract patients,ASA Ⅱ or Ⅲ grades,aged from 65 to 82 years old,scheduled for cataract surgery with retrobulbar nerve block were equally randomized into three groups by systematic sampling.The patients in three groups were given bolus infusion dexmedetomidine 0.5 μ g/kg before operation and group A was maintained by 0.2 μ g/ （kg· h）,group B was maintained by 0.4 μ g/（kg· h） and group C was maintained by 0.6 μ g/（kg· h）.Ramsay score,mean arterial blood pressure （MAP）,heart rate （HR）,respiratory rate,pulse oxygen saturation （SpO2） were recorded before anesthesia （T0）,after retrobulbar nerve block （T1）,and after sedative administration for 10 （T2）,20 （T3）,30 （T4）,60 min （T5）.Results The operation in three groups was successful.The scores of Ramsay at T2-T5 in three groups was significantly higher than that at T0 [group A：（2.6 ± 0.7）,（2.5 ±0.2）,（2.4 ±0.8）,（2.4 ± 0.3） scores vs.（2.0 ± 0.0） scores;group B：（3.0 ± 0.7）,（3.8 ± 0.7）,（4.2 ± 0.2）,（4.5 ± 0.2）scores vs.（2.0 ± 0.0） scores;group C：（3.8 ± 0.6）,（4.7 ± 0.4）,（5.2 ± 0.8）,（5.6 ± 0.6） scores vs.（2.0 ± 0.0） scores].The scores of Ramsay at T3-T5 in group C was significantly higher than that in group A and group B,the scores of Ramsay in group B was significantly higher than that in group A,there was significant difference （P ＜ 0.05）.The HR at T3-T5 in three groups was significantly lower than that at T0 [group A：（77 ± 5）,（76 ± 7）,（74 ± 12） times/min vs.（88 ± 12） times/min; group B：（72 ± 9）,（70 ± 8）,（70 ± 11）times/min vs.（90 ± 10） times/min;group C：（64 ±7）,（55 ±7）,（54 ±6） times/min vs.（88 ±9）times/min],the HR at T3-T5 in group C was significantly lower than that in group A and group B,there was significant difference （P ＜ 0.05）.The level of MAP,respiratory rate in three groups and interclass had no significant difference （P＞ 0.05）.There was no respiratory depression,nausea,vomiting and dizzy occurred.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 elderly patients with cataract surgery.