Sepsis and the microcirculation: the impact on outcomes

Abstract

Purpose of reviewAdvances in the treatment of septic shock have historically focused on resuscitation endpoints, mainly mean arterial pressure and cardiac output. As the definitions of sepsis and septic shock have shifted to focus on the diversity of causes of dysregulated host-response we have seen an emerging phenotype where tissue hypoxia persists despite adequate macrocirculatory parameters. Interest in the topic of microcirculation is re-emerging as validated bedside techniques for hemodynamic monitoring, such as video microscopes, are becoming available. We review the current understanding of how sepsis induced hypoperfusion with a focus on recent advances in monitoring the microcirculation, and how a proliferation of biomarkers and emerging therapeutic targets may impact future research. Recent findingsConventional hemodynamic monitoring systems fail to assess the microcirculation, and it's response to treatment. Lactate and venous oxygen saturations often drive biomarker-guided sepsis management. Visual assessments such as mottling and capillary refill time are often associated with predicting outcomes, but sometimes can have issues with inter-provider reliability. Microcirculatory damage can be observed sublingually and appears to have prognostic value. SummarySepsis is associated with changes in the microcirculation that can lead to tissue hypoxia and organ dysfunction. Further studies are needed to validate the usefulness of microcirculatory bedside tools in guiding resuscitative efforts.

Development and validation of a nomogram to predict the risk of sepsis-associated encephalopathy for septic patients in PICU: a multicenter retrospective cohort study

“…Other variables were significantly different between the SAE and non-SAE groups, including lactate levels. Elevated serum lactate levels indicate an oxygen supply/demand mismatch and microcirculatory impairment, inducing tissue ischemia and hypoxia in sepsis [ 40 ]. Previous studies have suggested that lactate is an important indicator for predicting the prognosis of patients with sepsis and is often used to evaluate disease severity and guide treatment [ 41 ].…”

Resuscitating the macro- vs. microcirculation in septic shock

“…Direct visualization techniques are therefore usually limited to sedated patients [28]. The other major problem is that specific microcirculatory goals are not yet well defined [29,30 ▪▪ ,31 ▪ –33 ▪ ,34].…”

Antithrombin as Therapeutic Intervention against Sepsis-Induced Coagulopathy and Disseminated Intravascular Coagulation: Lessons Learned from COVID-19-Associated Coagulopathy

“…For the earliest possible diagnosis of developing sepsis, which is considered a prerequisite for targeted therapeutic intervention, a combination of clinical observations and findings with various biomarkers has been recommended [ 21 ]. The path from infection, which at the beginning, in many cases, is not clearly identifiable, to sepsis is via organ dysfunction, which can occur at various sites and is the result of microcirculatory disturbances, most of which can be assessed and monitored including the hematologic system [ 22 , 23 ]. Preclinical studies have shown that in the so-called thrombo-inflammation of sepsis, among others, microcirculatory dysfunction is an early phenomenon [ 24 ], in which the endothelial glycocalyx plays a key role [ 25 ].…”