近红外光谱监测局部组织氧饱和度评估臂丛神经阻滞的效果

Near-infrared spectroscopy monitoring local tissue oxygen saturation for evaluating the effects of brachial plexus block

目的使用近红外光谱(NIRS)监测局部组织氧饱和度(StO_(2)),观察臂丛神经阻滞对前臂局部组织灌注的影响,并探讨StO_(2)评估臂丛神经阻滞效果的有效性。方法选择行择期骨科前臂手术患者43例,男24例,女19例,年龄18~64岁,BMI 20~28 kg/m^(2),ASAⅠ或Ⅱ级。超声引导下行锁骨上臂丛神经阻滞,注射0.375%罗哌卡因20 ml。根据阻滞后20 min是否成功分为两组:阻滞成功组(Y组)和阻滞失败组(N组)。记录阻滞即刻、阻滞后5、10、15、20 min时HR、MAP和SpO_(2),阻滞侧和非阻滞侧StO_(2),计算上述时点阻滞侧与非阻滞侧StO_(2)的差值(ΔStO_(2)),绘制阻滞后5、10 min时ΔStO_(2)的受试者工作特征(ROC)曲线预测阻滞效果,并计算曲线下面积(AUC)和95%可信区间(CI)。结果本研究最终阻滞成功38例(88.4%)。与非阻滞侧比较,阻滞后5、10、15、20 min Y组阻滞侧StO_(2)明显升高(P<0.05)。N组不同时点阻滞侧与非阻滞侧StO_(2)差异无统计学意义。与阻滞即刻比较,阻滞后5、10、15、20 min Y组ΔStO_(2)明显升高(P<0.05)。N组不同时点ΔStO_(2)差异无统计学意义。阻滞后5 minΔStO_(2)预测臂丛神经阻滞效果的AUC为0.884(95%CI 0.755~1.000),临界值3.867%,敏感性67.5%,特异性100%。阻滞后10 minΔStO_(2)预测臂丛神经阻滞效果的AUC为0.950(95%CI 0.885~1.000),临界值3.856%,敏感性90.0%,特异性100%。结论臂丛神经阻滞明显增加前臂局部组织氧饱和度,近红外光谱监测局部组织氧饱和度可作为早期预测臂丛神经阻滞效果的指标。

Objective To investigate the effects of supraclavicular brachial plexus block on tissue perfusion of the forearm and explore the feasibility of tissue oxygen saturation(StO_(2))in evaluating the success of brachial plexus block.Methods Forty-three patients undergoing elective orthopedic forearm surgery were selected,including 24 males and 19 females,aged 18-64 years,BMI 20-28 kg/m^(2),ASA physical statusⅠorⅡ.Ultrasound-guided supraclavicular brachial plexus block was performed,and 20 ml of 0.375%ropivacaine was injected.According to whether the block was successful or not 20 minutes after block,they were divided into a successful group(group Y)and a failure group(group N).HR,MAP and SpO_(2)at the moment of block and 5,10,15,and 20 minutes after block were recorded,and the StO_(2)on both the blocking side and the non-blocking side were recorded and the difference(ΔStO_(2))was calculated at the above time points.The receiver operating characteristic(ROC)curve ofΔStO_(2)at 5 and 10 minutes after block was drawn,and the area under the curve(AUC)and 95%confidence interval(CI)were calculated to predict the effect of brachial plexus block.Results Thirty-eight patients(88.4%)were successfully blocked in this study.Compared with the non-blocked side,the StO_(2)of the blocked side in group Y was significantly higher 5,10,15,and 20 minutes after the block(P<0.05).There was no significant difference in StO_(2)between the block side and the non-block side at different time points in group N.Compared with immediately after block,ΔStO_(2)in group Y was significantly higher 5,10,15,and 20 minutes after block(P<0.05).There was no significant difference inΔStO_(2)at different time points in group N.Five minutes after the block,the AUC ofΔStO_(2)to predict the effects of brachial plexus block was 0.884(95%CI 0.755-1.000),the cutoff value was 3.867%,the sensitivity was 67.5%,and the specificity was 100%.Ten minutes after the block,the AUC ofΔStO_(2)to predict the effects of brachial plexus block was 0.950(95%CI 0.885-1.000),the cutoff value was 3.856%,the sensitivity was 90.0%,and the specificity was 100%.Conclusion Brachial plexus block significantly increase the StO_(2)of forearm,and the monitoring of StO_(2)by NIRS can be used as an indicator for early prediction of the effects of brachial plexus block.