Br J Anaesth. 2015 Feb;114(2):235-43. doi: 10.1093/bja/aeu375.
We compared the new Pulsioflex and the Vigileo devices to measure cardiac index (CI) in critically ill patients. Both devices measure CI by pulse-contour analysis. The Pulsioflex device also allows an auto-calibration (not based on thermodilution).
Patients were included if we administered fluids (20 patients), reduced (20 patients), or increased (20 patients) the dose of norepinephrine. Before and after interventions, we measured CI provided by the Vigileo (CIVig) and Pulsioflex (CIPfx) devices before and after its auto-calibration. CI measured by transpulmonary thermodilution (CIthermo) was used as the reference.
Considering absolute values of CI (n=120), the percentage error was 59% for CIVig vs CIthermo and 40% for CIthermo vs CIPfx. Auto-calibrating CIPfx after interventions did not improve the percentage error between CIPfx and CIthermo (39%). Considering the fluid-induced changes in CI, the coefficient of correlation with changes in CIthermo was 0.50 for CIVig, and 0.73 for CIPfx (P=0.27). It was not significantly improved if CIPfx was auto-calibrated (r=0.64). Considering the norepinephrine-induced changes in CI, the coefficient of correlation with changes in CIthermo was 0.41 for CIVig. It tended to be better for CIPfx (r=0.71, P=0.07). It was not significantly improved by auto-calibration (r=0.53).
The Pulsioflex did not reliably estimate the absolute values of CI. For tracking fluid-induced changes in CI, the Pulsioflex was reliable, and also the Vigileo. For tracking norepinephrine-induced changes in CI, it was also reliable and tended to be better than the Vigileo. Auto-calibration allowed by the system did not improve its reliability.
我们比较了新的 Pulsioflex 和 Vigileo 设备来测量危重病患者的心指数（CI）。这两种设备都通过脉搏轮廓分析来测量 CI。Pulsioflex 设备还允许自动校准（不是基于热稀释法）。
如果我们给患者输液（20 例）、减少（20 例）或增加（20 例）去甲肾上腺素剂量，则将患者纳入研究。在干预前后，我们测量了自动校准前后 Vigileo（CIVig）和 Pulsioflex（CIPfx）设备提供的 CI。以经肺热稀释法（CIthermo）测量的 CI 作为参考。
考虑到 CI 的绝对值（n=120），CIVig 与 CIthermo 的百分比误差为 59%，而 CIthermo 与 CIPfx 的百分比误差为 40%。对干预后的 CIPfx 进行自动校准并没有改善 CIPfx 与 CIthermo 之间的百分比误差（39%）。考虑到 CI 因输液而发生的变化，CIVig 与 CIthermo 变化的相关系数为 0.50，CIPfx 的相关系数为 0.73（P=0.27）。如果对 CIPfx 进行自动校准，相关系数并没有显著提高（r=0.64）。考虑到 CI 因去甲肾上腺素而发生的变化，CIVig 与 CIthermo 变化的相关系数为 0.41。对于 CIPfx，相关系数趋于更好（r=0.71，P=0.07）。自动校准并没有显著提高其相关性（r=0.53）。
Pulsioflex 不能可靠地估计 CI 的绝对值。对于监测 CI 因输液而发生的变化，Pulsioflex 是可靠的，Vigileo 也是可靠的。对于监测 CI 因去甲肾上腺素而发生的变化，它也是可靠的，而且倾向于比 Vigileo 更好。系统允许的自动校准并没有提高其可靠性。
