Menezes Igor Alexandre Côrtes, Cunha Cláudio Leinig Pereira da, Carraro Júnior Hipólito, Luy Alain Marcio
Unidade de Terapia Intensiva, Hospital de Clínicas, Universidade Federal do Paraná - Curitiba (PR), Brasil.
Departamento de Clínica Médica, Hospital de Clínicas, Universidade Federal do Paraná - Curitiba (PR), Brasil.
Rev Bras Ter Intensiva. 2018 Apr-Jun;30(2):135-143. doi: 10.5935/0103-507X.20180027.
Microcirculation disturbances are implicated in the prognosis of septic shock. Microvascular hyporesponsiveness can be assessed by an oximetry-derived perfusion index and reactive hyperemia. Using this perfusion index, we investigated reactive hyperemia and its relationship with peripheral perfusion and clinical-hemodynamic parameters in septic shock.
Eighty-two patients were evaluated: 47 with septic shock and 35 controls. Tests were performed within 24 hours after admission. The perfusion index was evaluated before and after a 3-min blood flow occlusion using a time-response analysis for 5 min. The perfusion index was also evaluated in the hyperemic phases and was mainly derived by mechanosensitive (ΔPI0-60) and metabolic mechanisms (ΔPI60-120). Correlation tests were performed between reactive hyperemia and clinical-hemodynamic data.
Reactive hyperemia measured by the perfusion index was significantly lower in patients with septic shock, but this was only observed for the first 45 seconds after cuff-deflation. In the remaining period, there were no statistical differences between the groups. The peaks in the perfusion index were similar between groups, although the peak was reached more slowly in the septic group. Values of ΔPI0-60 were lower in shock [01% (-19% - -40%) versus 39% (6% - 75%); p = 0.001]. However, ΔPI60-120 was similar between the groups [43% (18% - 93%) versus 48% (18% - 98%); p = 0.58]. The time-to-peak of the perfusion index was correlated positively with the SOFA scores and negatively with C-reactive protein; the peak of the perfusion index was positively correlated with vasopressor doses; and the ΔPI60-120 values were positively correlated with C-reactive protein and vasopressor doses. No other significant correlations occurred.
This perfusion index-based study suggests that septic shock promotes initial peripheral vascular hyporesponsiveness and preserves posterior vascular reactivity to a considerable degree. These results demonstrate a time-dependent peripheral hyperemic response and a significant ischemic reserve in septic shock.
微循环障碍与感染性休克的预后相关。微血管低反应性可通过血氧饱和度衍生的灌注指数和反应性充血来评估。利用该灌注指数，我们研究了感染性休克中的反应性充血及其与外周灌注和临床血流动力学参数的关系。
对82例患者进行评估：47例感染性休克患者和35例对照。在入院后24小时内进行检测。使用5分钟的时间反应分析，在3分钟血流阻断前后评估灌注指数。还在充血期评估灌注指数，其主要由机械敏感机制（ΔPI0 - 60）和代谢机制（ΔPI60 - 120）得出。对反应性充血与临床血流动力学数据进行相关性检测。
感染性休克患者中通过灌注指数测量的反应性充血显著降低，但仅在袖带放气后的前45秒观察到。在其余时间段，两组之间无统计学差异。尽管感染组达到峰值的速度较慢，但两组灌注指数的峰值相似。休克组的ΔPI0 - 60值较低[01%（-19% - -40%）对39%（6% - 75%）；p = 0.001]。然而，两组之间的ΔPI60 - 120相似[43%（18% - 93%）对48%（18% - 98%）；p = 0.58]。灌注指数的达峰时间与序贯器官衰竭评估（SOFA）评分呈正相关，与C反应蛋白呈负相关；灌注指数的峰值与血管升压药剂量呈正相关；ΔPI60 - 120值与C反应蛋白和血管升压药剂量呈正相关。未出现其他显著相关性。
这项基于灌注指数的研究表明，感染性休克促进初始外周血管低反应性，并在相当程度上保留了后期血管反应性。这些结果证明了感染性休克中存在时间依赖性的外周充血反应和显著的缺血储备。
