Capillary Refill Time Response to a Rapid Fluid Challenge in Septic Shock Patients

In septic shock patients, the hemodynamic coherence between systemic, regional and microcirculatory blood flow can be tracked by "capillary refill time (CRT) response to an increase in stroke volume induced by a rapid fluid challenge". A parallel improvement in regional blood flow, microcirculation and hypoperfusion-related parameters should be expected in CRT-responders as reflection of preserved hemodynamic coherence. CRT non-response is associated with a more severe systemic inflammatory state, endothelial and microvascular dysfunction, and a higher adrenergic tone. The objective of this study is to determine if CRT response after a rapid fluid challenge signals a state of hemodynamic coherence as demonstrated by a parallel improvement in regional and microcirculatory blood flow in CRT-responders, and to explore the pathophysiological mechanisms associated to CRT non-response.