The full contents of the supplement are available online at http://ccforum.com/supplements/13/S5. Publication of the supplement has been supported find more info with funding from Hutchinson Technology Inc.
Septic shock is described as a distributive shock, requiring fluid and vasopressor administration [1]. In the recent past, evidence for microcirculatory failure as a motor of organ failure during septic shock has grown. It has been shown that distribution of flow within a tissue is impaired by oxygen shunting [2,3], cell aggregation, thrombosis [4], vaso-constriction [5] and/or tissue edema [6]. In the early phase of septic shock, early goal-directed cardiovascular optimization seems more efficient than the conventional strategy [7].

Despite this strategy, some patients continue to have abnormal microperfusion [8], which has been proposed to be targeted therapeutically with a fluid challenge [8], nitric oxide donors [9,10] or activated protein C [11,12]. Before integrating microperfusion parameters into clinical strategies, a better characterization and understanding of microperfusion abnormalities is needed.Among the tools available for microperfusion assessment, near-infrared spectroscopy (NIRS) seems promising. It has been shown in different life-threatening conditions that tissue hemoglobin oxygen saturation (StO2) characterizes tissue hypoperfusion and effectiveness of therapies in trauma [13-17], septic shock [18-22], and other acute systemic inflammatory conditions [23]. The large overlap of StO2 values between healthy subjects and septic shock patients [15-18] largely limits the interest of this parameter for individual care.

As a consequence, Carfilzomib a method to better evaluate the tissue micro-oxygenation in septic shock is needed. In this respect, a vascular occlusion test (VOT) combined with StO2 measurement has been proposed [17-20].Measuring StO2 with a VOT provides a functional test having several potential determinants. These determinants and their relative impact during septic shock remain to be clarified so they can be interpreted adequately before making decisions. The StO2 occlusion slope was shown to relate to tissue oxygen consumption [18,19,24], and the StO2 reperfusion slope was proposed to evaluate tissue flow reperfusion and vascular recruitment [18,22] and was found to be abnormal in septic shock [20-22]. The purpose of the present study was to quantify the micro-oxygenation parameters in a homogeneous septic shock population controlled for severity, to investigate the relationship of micro-oxygenation and macro-perfusion parameters, to investigate the relationship of NIRS parameters and skin laser Doppler (LD) in the same conditions, and to evaluate the association between micro-oxygenation parameters and outcome.