Dexmedetomidine Improves Microcirculatory Alterations in Patients with Initial Resuscitated Septic Shock.

BACKGROUND:The study was to investigate the effects of dexmedetomidine on microcirculation in patients with early septic shock despite initial resuscitation. METHODS:This was a single-center prospective study. Patients with early septic shock despite initial fluid resuscitation who still required norepinephrine to maintain target arterial pressure were enrolled. Hemodynamic and gas analysis variables, sublingual microcirculatory parameters were measured at baseline, and during the infusion of dexmedetomidine for 1 h (0.7mcg/kg/h). To elucidate the possible mechanisms of the effect of dexmedetomidine on microcirculation, after interim analysis, the dose-effect relationship of dexmedetomidine on microcirculation and catecholamine level were investigated at baseline, 1h after stabilization at different doses of dexmedetomidine (0.7 and 0.3 mcg/kg/h), and 2h after dexmedetomidine cessation. RESULTS:Forty-four patients with septic shock were enrolled after initial resuscitation. Compared with baseline, total and perfused vascular densities were statistically increased after infusion of dexmedetomidine, which was correlated with the dose of dexmedetomidine. During dexmedetomidine infusion, plasma norepinephrine, and dopamine level were significantly decreased. Changes in plasma norepinephrine level contributed to dexmedetomidine infusion were well correlated with changes in total and perfused vascular densities. CONCLUSIONS:In adult patients with resuscitated septic shock, dexmedetomidine improved microcirculation, which might be associated with plasma catecholamine level. However, double-blinded large sample studies should be performed to verify the results. Trial registration: Clinicaltrials.gov NCT02270281. Registered October 16, 2014.