摘要
Background:The relationship between macrocirculation and microcirculation remains controversial.The loss of coherence between microcirculation and macrocirculation has already been found in late-stage sepsis shock.The objective of this study was to determine the earliest possible time of detecting the loss of coherence between microcirculation and macrocirculation in early-stage endotoxemic shock.Methods:We randomized 24 female New Zealand white rabbits into two groups:endotoxemic shock group(n=14)and control group(n=10).Rabbits in the endotoxemic shock group were equipped with arterial and venous catheters and received an intravenous infusion of Escherichia coli lipopolysaccharide(LPS,2 mg/kg over 10 min).Rabbits in the control group received the same dose of saline infusion.Microcirculatory perfusion parameters were assessed in the sublingual mucosa using sidestream dark-field video microscopy.Systemic hemodynamics and blood lactate levels were measured at baseline and over a 120-min period.Results:Ninety minutes after completing LPS infusion,all animals in the endotoxemic shock group developed a hypodynamic septic condition,characterized by low cardiac output and increased systemic vascular resistance;120 min after completing LPS infusion,the mean arterial pressure decreased by 25%(P=0.01),confirming ongoing endotoxemic shock.However,significant decreases in sublingual microcirculatory parameters of small vessels(microvascular flow index,perfused vessel density,and proportion of small perfused vessels)were observed 30 min after completing LPS infusion(P=0.01,for all),and threshold decreases of 30%were found 60 min after completing LPS infusion(P=0.001,for all)in the endotoxemic shock group.Lactate levels significantly increased to more than 2 mm/L at 90 min and more than 4 mm/L at 120 min in the endotoxemic shock group(P=0.02 and P=0.01,respectively).Conclusions:Changes in microcirculatory perfusion precede changes in macrocirculation and lactate levels in a rabbit model of endotoxemia shock.Microcirculation,macrocirculation,and oxygen metabolism are distinct in early-stage endotoxic shock.
