Association between early arterial blood lactate clearance rate and central venous oxygen saturation monitoring and prognosis in patients with severe pneumonia

Objective To explore the value of early arterial blood lactate clearance rate and central venous oxygen saturation(ScvO2)monitoring in patients with severe pneumonia.Methods A total of 56 patients with severe pneumonia treated during the period from January 2012 to December 2013 were reviewed retrospectively.The arterial blood lactate concentration and ScvO2 were determined immediately after admission to hospital and 6 hours after admission to calculate the 6-hour lactate clearance rate.APACHE II score was evaluated at the same time.The patients were divided into three groups according to APACHE II score:10 to20(group A),20 to30(group B),≥30(group C).The three groups were compared in terms of early arterial blood lactate clearance rate and ScvO2 and estimate their association with the prognosis of patients.Results The initial arterial blood lactate concentration did not show significant difference between the three groups(P0.05).The early lactate clearance rate and ScvO2 at 6 hours in group C were significantly lower than in group B.The values in group B were significantly lower than in group A(P0.05).The mortality rate in group C was significantly higher than in group B,and the mortality rate in group B was significantly higher than in group A(P0.05).The APACHE II score of the dead patients was higher than that of the suevivors,but early lactate clearance rate and ScvO2 level were lower than those of the survivors(P0.05).APACHE II score was negatively correlated to early lactate clearance rate(r=0.661,P0.01)and early ScvO2level(r=0.579,P0.01).Conclusions Early lactate clearance rate and ScvO2 level are good indicators to reflect the severity of disease and predict the outcome in the patients with severe pneumonia.