脉搏灌注变异指数用于预测胃肠道手术中的液体反应性

The ability of pleth variability index to predict fluid responsiveness in the gastrointestinal tract surgery

目的 评估脉搏灌注变异指数（pleth variability index， PVI）在全身麻醉机械通气条件下预测胃肠道手术患者液体治疗反应和评估容量状况的能力。 方法 选择50例拟在全身麻醉下行腹部手术的患者，麻醉诱导后连续监测MAP、HR、CVP、心指数（cardiac index， CI）、每搏量指数（stroke volume index， SVI）、每搏量变异度（stroke volume variability， SVV）、PVI、灌注指数（perfusion index， PI）等血流动力学指标，手术开始后30 min以0.4 ml·kg-1·min-1的速率静脉输注羟乙基淀粉130/0.4氯化钠注射液（7 ml/kg），进行容量治疗反应的临床观察，将SVI变化百分比（ΔSVI）≥10％视为对容量治疗有反应。 结果 共48例患者完成了研究，其中28例对容量治疗有反应（R组），20例对容量治疗无反应（NR组）；R组患者SVV基础值［（13.8±1.2）%］和PVI基础值［（15.5±4.2）%］ 显著高于NR组［SVV（9.9±3.2）%，PVI（11.3±3.2）%］（P〈0.05）；SVV诊断阈值为10.5%，监测容量反应的灵敏度为80.0%，特异度为100％；PVI的诊断阈值为13.5%，监测容量反应的灵敏度为65.0%，特异度为75.0%；Pearson相关性分析显示，SVV的基础值与ΔSVI相关（r=0.639，P〈0.01），PVI的基础值与ΔSVI相关（r=0.420，P〈0.05）。 结论 PVI能够预测机械通气下胃肠道手术患者的容量治疗反应，其准确性与SVV类似。

Objective To evaluate the ability of pleth variability index （PVI） in predicting fluid responsiveness in the gastrointestinal tract surgery. Methods Fifty patients were enclosed in this study following anesthesia induction. PVI was continuously displayed by the Masimo Radical 7. All patients were also monitored with Vigileo/FloTrac system. Haemo-dynamic data such as cardiac index（CI）, stroke volume index（SVI）, stroke volume variability（SVV）, MAP, HR, CVP, PVI, perfusion index（PI） were recorded before and after volume expansion（voluven injection, 7 ml/kg）. Positive response was defined as an increase in SVI≥10% （△SVI≥10%）. Results Forty-eight patients finished the trial. Twenty-eight patients were regarded as positive responders and twenty patients were regarded as negative responders according to positive response criteria. SVV and PVI were significantly higher in the positive responders （13.8±1.2）% and （15.5±4.2）% than those in negative responders （9.9±3.2）% and （11.3±3.2）% respectively （P〈0.05）. The SVV diagnostic threshold is 10.5%. The volume expansion was able to discriminate the positive responder from the negative responders with a sensitivity of 80.0%. The specificity is 100%. The diagnostic threshold of PVI was 13.5%, the sensitivity is 65.0% and the specificity is 75.0%. There was relativity between PVI before volume expansion and change in SVI after volume expansion is r=0.420（P〈0.05）. Similar relativity of SVV is r=0.639（P〈0.01）. Conclusions PVI as a new dynamic index can predict fluid responsiveness non-invasively in the gastrointestinal tract surgery during general anesthesia.