脉搏灌注指数变异监测机体容量状况的临床研究

目的 评估脉搏灌注指数变异(PVI)在全身麻醉机械通气条件下预测患者容量治疗反应、评估容量状况的能力.方法 2009年8月至11月选择25例美国麻醉医师协会分级Ⅰ～Ⅱ级拟在全身麻醉下行腹部手术的患者,年龄25～74岁,麻醉诱导后连续监测平均动脉压、心率、中心静脉压、心指数(CI)、每搏输出量变异度(SW)、PVI、灌注指数(PI)等血流动力学指标,以0.4 ml·kg-1·min-1的速率静脉输注6%羟乙基淀粉(130/0.4)注射液,输注总量:7 ml/kg,将CI增加百分比(△CI)≥15%视为对容量治疗有反应.结果 对容量治疗有反应的患者SVV基础值16.0%±2.6%显著高于对容量治疗无反应患者的11.6%±1.4%(P＜0.05);对容量治疗有反应的患者PVI基础值20.5%±3.7%也显著高于对容量治疗无反应患者的13.8%±2.6%(P＜0.05);SVV诊断阈值为13.5%,监测容量反应的灵敏度为88.2%,特异度为87.5%;PVI的诊断阈值为15.5%,监测容量反应的灵敏度为88.2%,特异度为87.5%;Pearson相关性分析显示:SVV的基础值与△CI相关系数r=0.600(P＜0.01),PVI的基础值与△CI相关系数r=0.683(P＜0.01).结论 PVI,脉搏灌注指数周期性的变异能够预测机械通气患者在安静状态下的容量治疗反应,其准确性与有创测得的SVV相类似.     

心率和脉搏灌注变异指数对剖宫产脊麻后低血压的预测作用

目的探讨HR和脉搏灌注变异指数(PVI)对剖宫产脊麻后低血压的预测作用。方法选择择期脊麻下剖宫产的产妇80例,年龄18~40岁,BMI 20~40kg/m2,ASAⅠ或Ⅱ级。在L3-4间隙行硬腰联合麻醉。记录麻醉前后的HR、PVI、BP和MAP。探讨HR和PVI与脊麻后低血压的相关性。结果与未发生低血压的产妇比较,发生低血压的产妇HR基础值明显增快、PVI基础值明显增大(P 0.05)。HR基础值预测低血压的ROC曲线下面积为0.77(P 0.05),最佳阈值为≥84次/分,预测低血压的敏感度和特异度分别为70.7%和81.8%,阳性预测值和阴性预测值分别为91.1%和51.4%。PVI基础值预测低血压的ROC曲线下面积为0.74(P 0.05),最佳阈值为≥21%,预测低血压的敏感度和特异度分别为44.8%和95.5%,阳性预测值和阴性预测值分别为96.3%和39.2%。HR基础值联合PVI基础值预测低血压的ROC曲线下面积为0.86(P 0.05),最佳阈值为≥86次/分(HR)或≥21%(PVI),预测低血压的敏感度和特异度分别为82.8%和86.4%,阳性预测值和阴性预测值分别为92.5%和66.7%。结论脊麻前较大的心率基础值和脉搏灌注变异指数基础值与剖宫产脊麻后低血压相关,联合使用这两个指标可以用于临床预测剖宫产脊麻后低血压。     

脉搏灌注指数变异在复合麻醉术中诊断价值的研究

目的:比较全身麻醉(G)与全身麻醉复合硬膜外麻醉(GE)术中脉搏灌注指数变异(pleth variation index,PVI)对预测容量治疗反应性的诊断价值。方法:择期肝脏部分切除术病人56例,分为单纯G组和GE组。麻醉诱导后,G组病人硬膜外给予生理盐水,GE组病人给予0.5%布比卡因10 mL,手术开始20 min后,以6%羟乙基淀粉130/0.4氯化钠注射液250 mL快速扩容。记录用药前、硬膜外给药20 min后扩容前及扩容后3 min的PVI及心指数(cardic index,CI)。以△CI≥15%作为容量治疗有效的判断标准,对两组病人的PVI进行受试工作特征曲线分析,比较各时间点PVI的变化。结果:G组PVI监测容量治疗反应性的诊断阈值为12%,灵敏度和特异度分别为87.50%及83.33%,受试工作特征曲线下面积为0.88。GE组PVI的诊断阈值为7%,灵敏度为47.06%,特异度为33.33%,受试工作特征曲线下面积为0.39,不具备预测术中容量治疗反应性的价值。结论:GE中PVI预测容量治疗反应性的价值较单纯G显著降低。     

脉搏灌注变异指数在不同容量状态下预测容量反应的效果

目的探讨急性等容血液稀释(ANH)和急性高容血液稀释(AHH)期间脉搏灌注变异指数(PVI)预测患者容量变化的有效性。方法选取择期手术患者30例,男22例,女8例,年龄18～65岁,BMI30 kg/m~2,ASAⅠ或Ⅱ级。按照血液稀释的方法不同分成两组:等容血液稀释组(ANH组,n=15)和高容血液稀释组(AHH组,n=15)。ANH组从5个时点采集数据:基础值(全麻诱导插管后)、第1次抽出5%预估血容量(EBV)、第2次抽出5%EBV、第1次输注同等容量的6%羟乙基淀粉溶液(HES)、第2次输注5%EBV的HES;AHH组从3个时点采集数据:基础值、第1次输注5%EBV的HES、第2次输注5%EBV的HES。记录以上时点的PVI,对PVI和不同容量状态的反应进行相关性分析。结果 ANH组的基础血容量与PVI相关性较低(r=0.259,P=0.352);在ANH放血时,放血5%EBV与PVI(r=0.530,P0.05)及放血10%EBV与PVI(r=0.547,P0.05)相关性中等;在ANH回输时,回输5%EBV与PVI(r=-0.164,P=0.560)及回输10%EBV与PVI(r=-0.160,P=0.569)相关性较低。AHH组的基础血容量与PVI相关性较低(r=0.146,P=0.603);在AHH扩张容量时,扩容5%EBV与PVI(r=-0.538,P0.05)及扩容10%EBV与PVI(r=-0.577,P0.05)相关性中等。结论不论是低容量还是高容量状态,PVI均能够预测容量反应,但敏感性一般。     

气腹对腹腔镜输尿管切开取石术患者每搏变异度和脉搏灌注变异指数的影响

目的观察CO₂气腹对腹腔镜输尿管切开取石术患者每搏变异度（SVV）和脉搏灌注变异指数（PVI）的影响。方法择期全麻下行腹腔镜输尿管切开取石术患者70例,常规麻醉诱导后气管插管,控制呼吸,潮气量10ml/kg,呼吸频率8-12次/分。于气腹前以及气腹后两个时间点采用FloTrac/Vigileo系统测量SVV,同步采用Masimo Radical 7脉搏血氧仪测量PVI。结果与气腹前比较,气腹后患者SVV、PVI值升高,具有统计学意义（P<0.05）。相关性分析显示:气腹前后SVV、PVI分别与CO呈负相关（依次为r=-0.619,P<0.01;r=-0.753,P<0.01）;而PVI与SVV均呈正相关（r=0.638,P<0.01）。结论 CO₂气腹后SVV、PVI均显著升高,且与气腹前后两者之间存在显著的线性相关性,但气腹不影响PVI与SVV的良好相关性。     

每搏输出量变异评估腹腔高压家猪液体反应性的有效性

目的探讨每搏输出量变异(SVV)评价不同腹腔高压家猪液体反应性的有效性。方法选择实验家猪40只,经颈动脉释放家猪30%血容量,维持家猪低血容量状态,并按随机数字表法随机分为四组,采用氮气气腹法分别维持腹腔压力(IAP)为0 mm Hg(L0组)、15 mm Hg(L15组)、25mm Hg(L25组)和35mm Hg(L35组),稳定30min后给予HES 500 ml液体复苏,采用脉搏轮廓持续心输出量监测(PiCCO)法分别于基线水平、低血容量模型建立后、液体复苏后测家猪SVV以及液体复苏前后每搏输出量(SV)。结果 L0组和L15组家猪SVV与SV呈明显正相关(r分别为0.888和0.942,P0.05),而L25组和L35组SVV与SV均无明显相关性(r分别为0.068和-0.114)。结论 IAP轻度升高(IAP≤15mm Hg)时,SVV可作为评估液体反应性的有效指标,重度腹腔高压(IAP≥25mm Hg)时,SVV不能有效评估液体反应性。     

脑血管手术机械通气患者灌注变异指数与CVP和MAP的相关性研究

目的 研究脑血管手术机械通气患者灌注变异指数(PVI)与CVP和MAP的相关性.方法 脑血管手术患者15例,术中均需自体血回输,术前30 min内输注6%羟乙基淀粉130/0.4( HES)500 ml,术中输注复方氯化钠10ml·kg-1·h-1.机械通气采用容量控制模式,潮气量8 ml/kg,保持气道压在18 cm H2O左右.记录诱导前(T0)、诱导后(T1)、输注HES后(T2)、自体血回输前(T3)、自体血回输后(T4)的PVI、CVP和MAP.结果 PVI的变化与CVP、MAP的变化呈负相关,相关系数分别为-0.82(P＜0.05)和-0.73(P＜0.05).结论 PVI可以作为脑血管手术机械通气患者血流动力学变化的有效判断指标,其与CVP和MAP呈负相关.     

液体反应性预测指标研究进展

液体治疗是围手术期液体管理的重点、难点,过与不及都可对机体组织造成损伤。机体对液体反应性是指导液体治疗管理的重点。文章综述了目前预测液体反应性常用指标的基本原理、影响因素、不同手术中的应用价值和局限性,从而为患者围手术期合理的液体治疗管理提供依据,选择合适的液体反应性预测指标,作出及早诊断和处理。     

消化道液体灌注测压技术

消化道动力障碍性疾病是最常见的消化系统疾病,由于发病机制不明,症状无特异性,缺乏有效的诊疗手段。消化道灌注测压可反映消化道动力性疾病的生理病理改变情况,准确反映消化道腔内基础压力及其压力变化的频率、幅度、动力指数等,对胃肠运动功能疾病的诊治有较高的价值。该技术被广泛应用于各种消化道动力监测的临床及基础试验中,对消化系统疾病的诊疗及胃肠外科术后消化道运动功能的评价有很大帮助作用。     

灌注指数变异度监测伤害性刺激反应的评价

目的评价灌注指数变异度（pleth variability index,PVI）对伤害性刺激反应的监测作用。方法择期行胃部手术患者,按随机数字表法随机分为两组：单纯气管插管全身麻醉（GA）组和全身麻醉联合硬膜外阻滞（GE）组,每组30例。硭录手术切皮前后的心率（heart rate,HR）、平均桡动脉压mean radial artery blood pressure,MBP）、灌注指数（perfusion index,P1）和PVI。结果两组手术切皮前后,HR和MBP变化差异无统计学意义（P〉0．05）。GA组PI在手术切皮后1min和5rain均显著下降,切皮前为（2．7±0．6）％,手术切皮后1min和5min分别降低为（0．77±0．28）％和（0．7±0．4）％。PVI均大幅增加（P〈0．05）,切皮前为（10．8±2．6）％,手术切皮后1min和5min分别（23．7±3．6）％和（26．6±4．1）％;GE组切皮前后PI和PVI差异无统计学意义（P〉0．05）。两组组间比较,手术切皮前各项指标差异无统计学意义。手术切皮后1min和5min,HR和MBP差异无统计学意义（P〉0．05）,PI和PVI差异有统计学意义（P〈0．05）。比较切皮前后PI和PVI呈显著负相关。结论PVI是一种无创监测手术伤害性刺激反廊的有效指标。     

Goal directed fluid optimization using Pleth variability index versus corrected flow time in cirrhotic patients undergoing major abdominal surgeries

PurposeSeveral studies have shown that hemodynamic and fluid optimization may result in improved outcome. The aim of this study was to compare between two methods of goal directed fluid optimization using protocols guided by corrected flow time (FTc) of the transesophageal doppler versus Pleth variability index (PVI group) in cirrhotic patients undergoing major abdominal surgeries.MethodsSixty cirrhotic patients Child A to B scheduled for major abdominal surgery were randomized into two groups. In both groups 500 mL of Ringer's acetate was infused during induction followed by a 2 mL/kg/h continuous infusion. In FTc group (n = 30) patients with (FTc) less than 350 ms were treated with bolus of fluid challenge according to a preset protocol. In PVI group (n = 30), PVI higher than 13% patients were given 250 mL of fluid bolus.ResultsThere was no significant differences in the volume of crystalloids or colloids transfused to both groups with a mean value of 2670 ± 1680 mL and 670 ± 330 mL in the FTc guided fluid group while mean values were 2730 ± 1760 mL and 690 ± 290 mL in the PVI fluid guided group respectively (P > 0.05). Also, there was no significant differences between groups regarding the intra or postoperative hemodynamic parameters. There was no significant difference regarding the overall morbidity or the hospital stay between the two groups (P > 0.05).ConclusionsIn conclusion, in cirrhotic patients Child A to B, FTc and PVI were considered to be adequate methods for perioperative fluid optimization, However, combination of every clinical finding, recent and conventional monitoring techniques to all haemodynamic data should be applied whenever possible.     

Role of pleth variability index for predicting hypotension after spinal anesthesia for cesarean section

BackgroundHypotension is frequently observed after spinal anesthesia for cesarean section and can be detrimental to both mother and baby. We investigated the role of the pleth variability index for predicting hypotension after spinal anesthesia for cesarean section.MethodsEighty-five parturients undergoing elective cesarean section under spinal anesthesia were enrolled. We recorded pleth variability index and perfusion index before anesthesia, and blood pressure, heart rate and pulse oxygen saturation before and after anesthesia. The association between baseline pleth variability index and perfusion index with hypotension after spinal anesthesia was explored using multivariate analysis.ResultsHypotension occurred in 42 parturients. Baseline pleth variability index was higher in parturients who experienced hypotension than in those who did not (P < 0.05), although there was no difference in baseline perfusion index. The area under the receiver operating characteristic curve was 0.66 for baseline pleth variability index for the prediction of hypotension (P < 0.05). Baseline pleth variability index was significantly related to the incidence of hypotension (P = 0.017), but was not significantly related to the magnitude of the decrease in systolic blood pressure. Baseline perfusion index was not significantly related to the magnitude of the decrease in systolic blood pressure.ConclusionGreater baseline pleth variability index was associated with hypotension after spinal anesthesia for cesarean section, but may not be a clinically useful predictor.     

Accuracy of the pleth variability index to predict fluid responsiveness depends on the perfusion index

Background: Respiratory variations in plethysmographic waveform amplitudes derived from pulse oximetry are believed to predict fluid responsiveness. The non‐invasive pleth variability index (PVI) is a variable based on the calculation of changes in the perfusion index (PI). The aim of the following study was to examine whether the predictive power of PVI depends on different values of PI. Methods: Eighty‐one patients undergoing elective coronary artery surgery were studied before operation: at baseline after induction of anaesthesia and during passive leg raising (PLR). Each patient was monitored with central venous pressure (CVP), the PiCCO monitor and the non‐invasive Masimo monitoring system. Stroke volume index by transpulmonary thermodilution (SVI_TPTD), pulse pressure variation (PPV), stroke volume variation (SVV) and systemic vascular resistance index (SVRI) were measured using the PiCCO monitoring system. PI and PVI were obtained by pulse oximetry. Results: Responders were defined to increase their SVI_TPTD>15% after PLR. The highest area under the curve (AUC) was found for PPV (AUC: 0.83, P<0.0001) and SVV (AUC: 0.72, P=0.002), in contrast to PVI (AUC: 0.60, P=0.11) and CVP (AUC: 0.60, P=0.13). The accuracy of PVI to predict fluid responsiveness was improved on analysing patients with higher PI values. PI of about 4% (n=45) achieved statistical significance (AUC: 0.72, P=0.01). Conclusion: The PVI was not able to predict fluid responsiveness with sufficient accuracy. In patients with higher perfusion states, the PVI improved its ability to predict haemodynamic changes, strongly suggesting a relevant influence of the PI on the PVI.     

胃肠外科围手术期的液体治疗

外科液体治疗一直是关注的热点并存在争议。本文就液体治疗对术后肠道功能的影响、液体治疗对外科预后的影响和急性弥漫性腹膜炎围手术期液体治疗三方面进行讨论,应该注意在低灌注状况下胶体的补充和适当的晶／胶体比例。不同液体种类的选择在近年来的研究中未显示出远期效果的显著差异。关注2012SSC严重脓毒症及脓毒性休克指南更新中液体治疗新证据。     

Esmolol hypotension maintains tissue perfusion during myomectomy judged by Masimo monitoring of regional cerebral oxygen saturation and pleth variability index

Objectives

To evaluate outcome of elective abdominal myomectomy under esmolol hypotensive anesthesia (HA) compared to normotensive anesthesia (NA).

Non-invasive prediction of fluid responsiveness in infants using pleth variability index

This prospective study assessed whether respiratory variations in velocity time integral, peak blood flow velocity and non-invasive pleth variability index are useful measurements in infants undergoing congenital heart surgery and determined threshold values that may help guide fluid administration. In 27 infants receiving mechanical ventilation, of mean (SD) weight 10.4 (6.3) kg, 13 increased their stroke volume index ≥ 15% following a fluid challenge and 14 did not. The best area under the receiver operating characteristic curve was for the echocardiographic-derived variables respiratory variation in blood peak flow velocity (area under the ROC curve = 0.92; p = 0.0002) and respiratory variation of the velocity time integral (area under the ROC curve = 0.84; p = 0.002). The pleth variability index also predicted fluid responsiveness (area under the ROC curve = 0.79; p = 0.01), in contrast to heart rate (area under the ROC curve = 0.53; p = 0.75) and central venous pressure (area under the ROC curve = 0.57; p = 0.52).