Servicio de Terapia Intensiva, Sanatorio Otamendi y Miroli, Buenos Aires, Argentina.
Crit Care Med. 2012 May;40(5):1443-8. doi: 10.1097/CCM.0b013e31823dae59.
The microcirculation of septic patients has been characterized only semiquantitatively. Our goal was to characterize the sublingual microcirculation in healthy volunteers and patients with septic shock quantitatively. Our hypotheses were that 1) hyperdynamic blood flow is absent in septic shock; 2) nonsurvivors show more severe alterations than survivors; and 3) quantitative and semiquantitative microcirculatory parameters have a similar performance.
Prospective, observational study.
Teaching intensive care unit in a university-affiliated hospital.
Twenty-five normal volunteers and 25 patients with septic shock.
None.
The sublingual microcirculation was evaluated by means of sidestream dark field imaging. Semiquantitative and quantitative microcirculatory parameters were determined through the use of applied software. Septic patients showed decreased perfused capillary density (13.2±4.4 mm/mm² vs. 16.6±1.6 mm/mm²), proportion of perfused capillaries (0.78±0.23 vs. 1.00±0.01), microvascular flow index (2.15±0.61 vs. 2.97±0.03), and red blood cell velocity (830±183 µm/sec vs. 1332±187 µm/sec) along with increased heterogeneity flow index (1.64±1.14 vs. 0.25±0.19) compared with controls. No differences were found in total capillary density (16.9±2.2 vs. 16.7±1.6). Only 4% of capillaries analyzed showed red blood cell velocities>75th percentile of the velocities of the normal volunteers. The nonsurvivors exhibited decreased perfused capillary density, proportion of perfused capillaries, and microvascular flow index along with increased heterogeneity flow index compared with the survivors. The correlations between microvascular flow index and proportion of perfused capillaries, total capillary density and number of grid-crossing capillaries, and red blood cell velocities and microvascular flow index gave high R values (0.92, 0.65, and 0.52, respectively; p<.0001 for all).
The main characteristics of sublingual microcirculation in patients with septic shock are hypoperfusion and increased flow heterogeneity. Hyperdynamic microvascular blood flow was not found. Nonsurvivors showed more severe alterations than survivors. Quantitative and semiquantitative microcirculatory variables displayed similar behaviors.
目前对脓毒症患者的微循环只能进行半定量描述。本研究的目的是对健康志愿者和感染性休克患者的舌下微循环进行定量描述。我们的假设是：1）血流高动力不存在于感染性休克；2）非幸存者的改变比幸存者更严重；3）定量和半定量的微循环参数具有相似的性能。
前瞻性观察性研究。
大学附属医院的重症监护病房。
25 名正常志愿者和 25 名感染性休克患者。
无。
通过侧流暗场成像评估舌下微循环。通过使用应用软件确定半定量和定量微循环参数。感染性休克患者的灌注毛细血管密度（13.2±4.4mm/mm² 与 16.6±1.6mm/mm²）、灌注毛细血管比例（0.78±0.23 与 1.00±0.01）、微血管血流指数（2.15±0.61 与 2.97±0.03）和红细胞速度（830±183µm/sec 与 1332±187µm/sec）降低，异质性血流指数（1.64±1.14 与 0.25±0.19）升高，与对照组相比。总毛细血管密度（16.9±2.2mm/mm² 与 16.7±1.6mm/mm²）无差异。分析的毛细血管中只有 4%的红细胞速度超过正常志愿者速度的第 75 百分位数。与幸存者相比，非幸存者的灌注毛细血管密度、灌注毛细血管比例和微血管血流指数降低，异质性血流指数增加。微血管血流指数与灌注毛细血管比例、总毛细血管密度与网格交叉毛细血管数量、红细胞速度与微血管血流指数之间的相关性均具有较高的 R 值（分别为 0.92、0.65 和 0.52；所有 P 值均<.0001）。
感染性休克患者舌下微循环的主要特征是灌注不足和血流异质性增加。未发现高动力微血管血流。非幸存者的改变比幸存者更严重。定量和半定量的微循环变量表现出相似的行为。
