He Huai-Wu, Liu Wang-Lin, Zhou Xiang, Long Yun, Liu Da-Wei
Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing 100730, China.
Chin Med J (Engl). 2020 Sep 20;133(18):2146-2152. doi: 10.1097/CM9.0000000000001017.
The peripheral perfusion index (PI), as a real-time bedside indicator of peripheral tissue perfusion, may be useful for determining mean arterial pressure (MAP) after early resuscitation of septic shock patients. The aim of this study was to explore the response of PI to norepinephrine (NE)-induced changes in MAP.
Twenty septic shock patients with pulse-induced contour cardiac output catheter, who had usual MAP under NE infusion after early resuscitation, were enrolled in this prospective, open-label study. Three MAP levels (usual MAP -10 mmHg, usual MAP, and usual MAP +10 mmHg) were obtained by NE titration, and the corresponding global hemodynamic parameters and PI were recorded. The general linear model with repeated measures was used for analysis of variance of related parameters at three MAP levels.
With increasing NE infusion, significant changes were found in MAP (F = 502.46, P < 0.001) and central venous pressure (F = 27.45, P < 0.001) during NE titration. However, there was not a significant and consistent change in continuous cardiac output (CO) (F = 0.41, P = 0.720) and PI (F = 0.73, P = 0.482) at different MAP levels. Of the 20 patients enrolled, seven reached the maximum PI value at usual MAP -10 mmHg, three reached the maximum PI value at usual MAP, and ten reached the maximum PI value at usual MAP +10 mmHg. The change in PI was not significantly correlated with the change in CO (r = 0.260, P = 0.269) from usual MAP -10 mmHg to usual MAP. There was also no significant correlation between the change in PI and change in CO (r = 0.084, P = 0.726) from usual MAP to usual MAP +10 mmHg.
Differing MAP levels by NE infusion induced diverse PI responses in septic shock patients, and these PI responses may be independent of the change in CO. PI may have potential applications for MAP optimization based on changes in peripheral tissue perfusion.
外周灌注指数（PI）作为外周组织灌注的实时床旁指标，可能有助于确定感染性休克患者早期复苏后的平均动脉压（MAP）。本研究旨在探讨PI对去甲肾上腺素（NE）诱导的MAP变化的反应。
本前瞻性、开放标签研究纳入了20例使用脉搏诱导轮廓心输出量导管的感染性休克患者，这些患者在早期复苏后接受NE输注时具有正常的MAP。通过NE滴定获得三个MAP水平（正常MAP -10 mmHg、正常MAP和正常MAP +10 mmHg），并记录相应的整体血流动力学参数和PI。采用重复测量的一般线性模型对三个MAP水平下的相关参数进行方差分析。
在NE滴定过程中，随着NE输注量增加，MAP（F = 502.46，P < 0.001）和中心静脉压（F = 27.45，P < 0.001）出现显著变化。然而，在不同MAP水平下，连续心输出量（CO）（F = 0.41，P = 0.720）和PI（F = 0.73，P = 0.482）没有显著且一致的变化。在纳入的20例患者中，7例在正常MAP -10 mmHg时达到最大PI值，3例在正常MAP时达到最大PI值，10例在正常MAP +10 mmHg时达到最大PI值。从正常MAP -10 mmHg到正常MAP，PI的变化与CO的变化无显著相关性（r = 0.260，P = 0.269）。从正常MAP到正常MAP +10 mmHg，PI的变化与CO的变化之间也无显著相关性（r = 0.084，P = 0.726）。
通过NE输注改变MAP水平在感染性休克患者中引起了不同的PI反应，且这些PI反应可能独立于CO的变化。PI可能基于外周组织灌注的变化在MAP优化方面具有潜在应用。
