基于肺电阻抗成像评价肌间沟臂丛神经阻滞对肺通气的影响

Effect of Interscalene Brachial Plexus Block on Pulmonary Ventilation Based on Pulmonary Electrical Impedance Tomography

目的 采用肺电阻抗成像(EIT)法评价不同浓度罗哌卡因肌间沟臂丛神经阻滞对肺通气的影响。方法 选择2021年10月-2022年4月于安徽医科大学第二附属医院拟择期行肌间沟臂丛神经阻滞麻醉的上肢手术患者75例,采用随机数字表法分低浓度组(A组)、中浓度组(B组)和高浓度组(C组),每组25例。三组患者均在超声引导下行肌间沟入路臂丛神经阻滞,分别在肌间沟注射0.25%、0.33%和0.50%的罗哌卡因20 ml。连续监测EIT,评估肺通气变化;进行改良Bromage评分,评估运动阻滞情况;记录阻滞前(T0)、阻滞后10 min(T1)、阻滞后20 min(T2)和阻滞后30 min(T3)通气中心(CoV)、依赖静止区(DSS)和非依赖静止区(NSS)的面积百分比及改良Bromage评分。结果 与T0相比,T1、T2和T3时A组、B组和C组的NSS和DSS均增加(P<0.05);与T0相比,T2和T3时A组及T1、T2和T3时B组和C组的CoV均增加(P<0.05);T1、T2和T3时,B组和C组的NSS和DSS高于A组(P<0.05);T1时,B组和C组的CoV高于A组(P<0.05);与T0相比,3组各时点的改良Bromage评分均增加(P<0.05);T1时,B组改良Bromage评分高于A组(P<0.05);T1、T2和T3时,C组的改良Bromage评分高于A组(P<0.05)。结论 肺电阻抗成像可以实时监测肺局部通气变化,用于观察肌间沟臂丛神经阻滞对肺通气的影响;另外,更高浓度的局麻药物可更快的引起肺通气变化。

Objective To evaluate the effect of different concentrations of ropivacaine interscalene brachial plexus block on pulmonary ventilation by pulmonary electrical impedance imaging(EIT).Methods From October 2021 to April 2022,75 patients undergoing upper limb surgery with interscalene brachial plexus block anesthesia in the Second Affiliated Hospital of Anhui Medical University were selected. They were randomly divided into low concentration group(group A), medium concentration group(group B) and high concentration group(group C) by random number table method, with 25cases in each group. Ultrasound-guided interscalene brachial plexus block was performed in all three groups, and 0.25%, 0.33% and 0.50% ropivacaine20 ml were injected into the interscalene. Continuous monitoring of EIT to assess changes in lung ventilation;modified Bromage score was used to evaluate motor block. The area percentage of ventilation center(CoV), dependent resting area(DSS) and independent resting area(NSS) and modified Bromage score were recorded before block(T0), 10 min after block(T1), 20 min after block(T2) and 30 min after block(T3).Results Compared with T0, the NSS and DSS of group A, group B and group C increased at T1, T2 and T3(P<0.05). Compared with T0, the CoV of group A at T2 and T3 and that of group B and C at T1, T2 and T3 increased(P<0.05). At T1, T2 and T3, NSS and DSS in group B and group C were higher than those in group A(P<0.05). At T1, the CoV of group B and group C was higher than that of group A(P<0.05). Compared with T0, the modified Bromage score of the three groups increased at each time point(P<0.05). At T1, the modified Bromage score of group B was higher than that of group A(P<0.05). At T1, T2 and T3, the modified Bromage score of group C was higher than that of group A(P <0.05).Conclusion Electrical impedance imaging can monitor the changes of local lung ventilation in real time, and can be used to observe the effect of interscalene brachial plexus block on the pulmonary ventilation,higher concentrations of local anesthetics can produce more faster and significant changes in lung ventilation.