Performance of cardiac output measurement derived from arterial pressure waveform analysis in patients requiring high-dose vasopressor therapy
Performance of cardiac output measurement derived from arterial pressure waveform analysis in patients requiring high-dose vasopressor therapy
复制标题
DOI：
10.1093/bja/aer066
复制
发表时间：
2011-06-01
影响因子：
9.8
通讯作者：
Rex, S.
中科院分区：
文献类型：
--
作者：
Metzelder, S.;Coburn, M.;Rex, S.
背景。无外部校准（FloTrac/Vigileo (TM)）的心输出量（APCO）的动脉压力波形分析严重依赖于血管张力的计算，这需要对底层软件算法进行多次改进。我们假设高剂量血管加压剂治疗引起的血管张力变化会影响APCO测量的准确性，而不依赖于FloTrac软件版本。在这项前瞻性观察性研究中，我们对24例接受血管加压治疗蛛网膜下腔出血后脑血管痉挛的患者进行了未经校准的APCO测量与经肺热稀释心输出量（TPCO）测量的有效性进行了评估。患者接受血管活性支持，[平均（SD）] 0.53 (0.46) mu g kg(-1) min（-1）去甲肾上腺素，平均动脉压为104 (14)mm Hg，平均全身血管阻力为943 (248)dyn s(-1) cm（-5）。心输出量（CO）数据对（158）同时通过APCO和TPCO测量获得。TPCO从5.2到14.3升min(-1)， APCO从4.1到13.7升min（-1）。偏差和一致性限制分别为0.9和2.5升min(-1)，导致使用第二代FloTrac (R)软件分析的68对数据的总体百分比误差为29.6%，使用第三代软件分析的90对数据的总体百分比误差为27.9%。参考技术的精度为2.6%，而第二代和第三代软件的APCO测量精度分别为29.5%和27.9%。对于两种软件版本，偏倚（TPCO-APCO）与全身血管阻力呈负相关。在需要大剂量血管加压剂支持的神经外科患者中，未校准CO测量的精度取决于全身血管阻力。第三种软件算法的引入并没有改善第二种软件版本观测到的APCO测量精度不足（> 20%）。
Background. Arterial pressure waveform analysis of cardiac output (APCO) without external calibration (FloTrac/Vigileo (TM)) is critically dependent upon computation of vascular tone that has necessitated several refinements of the underlying software algorithms. We hypothesized that changes in vascular tone induced by high-dose vasopressor therapy affect the accuracy of APCO measurements independently of the FloTrac software version.Methods. In this prospective observational study, we assessed the validity of uncalibrated APCO measurements compared with transpulmonary thermodilution cardiac output (TPCO) measurements in 24 patients undergoing vasopressor therapy for the treatment of cerebral vasospasm after subarachnoid haemorrhage.Results. Patients received vasoactive support with [mean (SD)] 0.53 (0.46) mu g kg(-1) min(-1) norepinephrine resulting in mean arterial pressure of 104 (14) mm Hg and mean systemic vascular resistance of 943 (248) dyn s(-1) cm(-5). Cardiac output (CO) data pairs (158) were obtained simultaneously by APCO and TPCO measurements. TPCO ranged from 5.2 to 14.3 litre min(-1), and APCO from 4.1 to 13.7 litre min(-1). Bias and limits of agreement were 0.9 and 2.5 litre min(-1), resulting in an overall percentage error of 29.6% for 68 data pairs analysed with the second-generation FloTrac (R) software and 27.9% for 90 data pairs analysed with the third-generation software. Precision of the reference technique was 2.6%, while APCO measurements yielded a precision of 29.5% and 27.9% for the second- and the third-generation software, respectively. For both software versions, bias (TPCO-APCO) correlated inversely with systemic vascular resistance.Conclusions. In neurosurgical patients requiring high-dose vasopressor support, precision of uncalibrated CO measurements depended on systemic vascular resistance. Introduction of the third software algorithm did not improve the insufficient precision (> 20%) for APCO measurements observed with the second software version.