Severe abnormalities in microvascular perfused vessel density are associated to organ dysfunctions and mortality and can be predicted by hyperlactatemia and norepinephrine requirements in septic shock patients.

PURPOSE: The aims of this study are to determine the general relationship of perfused vessel density (PVD) to mortality and organ dysfunctions and to explore if patients in the lowest quartile of distribution for this parameter present a higher risk of bad outcome and to identify systemic hemodynamic and perfusion variables that enhances the probability of finding a severe underlying microvascular dysfunction. MATERIALS AND METHODS: This is a retrospective multicenter study including 122 septic shock patients participating in 7 prospective clinical trials on which at least 1 sublingual microcirculatory assessment was performed during early resuscitation. RESULTS: Perfused vessel density was significantly related to organ dysfunctions and mortality, but this effect was largely explained by patients in the lowest quartile of distribution for PVD (P = .037 [odds ratio {OR}, 8.7; 95% confidence interval {CI}, 1.14-66.78] for mortality). Hyperlactatemia (P < .026 [OR, 1.23; 95% CI, 1.03-1.47]) and high norepinephrine requirements (P < .019 [OR, 7.04; 95% CI, 1.38-35.89]) increased the odds of finding a severe microvascular dysfunction. CONCLUSIONS: Perfused vessel density is significantly related to organ dysfunctions and mortality in septic shock patients, particularly in patients exhibiting more severe abnormalities as represented by the lowest quartile of distribution for this parameter. The presence of hyperlactatemia and high norepinephrine requirements increases the odds of finding a severe underlying microvascular dysfunction during a sublingual microcirculatory assessment.

Microcirculatory dysfunction in sepsis.

In the last few years, an important body of knowledge has been developed showing the pathophysiological relevance of the sublingual microcirculation in the development of multiorgan failure associated with sepsis. In addition to the compelling experimental evidence, the development of new videomicroscopic techniques allows now the evaluation of the microcirculation in critically ill patients. Consequently, the sublingual microcirculation can be easily monitored at bedside. Therefore, studies performed in the sublingual area show that severe microcirculatory sublingual alterations are present in septic patients. Moreover, these alterations have an important prognostic value. Finally, sublingual microvascular alterations can be modified by therapeutic interventions. In this article, we review relevant information related to the pathophysiology of the microcirculation in health and disease with special reference to the behavior of the mesenteric territory during shock states and the alterations of sublingual microcirculation in septic patients as well as their responses to different therapeutic approaches.