The Relationship Between The Diameter Of Inferior Vena Cava And Lactate Clearance In Patients With Septic Shock

Research backgroundAdequate fluid resuscitation in patients with septic shock can significantly reduce the mortality of patients with sepsis,but excessive fluid load can cause serious adverse consequences for critically ill patients,therefore,accurate and timely detection of hemodynamic,the treatment and prognosis in patients have important clinical significance.The hemodynamic parameters of patients with low blood volume are mainly dependent on invasive monitoring,which is complicated and has more complications.In recent years,with the popularity of bedside ultrasound in intensive care units,it is considered to be a more convenient and rapid method to evaluate the hemodynamic parameters of the patients by bedside ultrasound.A large number of experiments show that lactate clearance rate can be used as a reliable indicator to evaluate the improvement of tissue perfusion and oxygen metabolism in septic shock patients.However,it has not been found whether to monitor the diameter of the inferior vena cava and the lactic acid in the process of fluid resuscitation in patients with septic shock and whether the variability of inferior vena cava diameter and lactic acid clearance is related.In this study,we investigated the feasibility of ultrasonog-raphy in the diagnosis of fluid resuscitation in patients with septic shock.ObjectiveTo observe the changes of the diameter of inferior vena cava and the changes of arterial blood lactate before and after fluid resuscitation.To investigate the effect of fluid resuscitation on changes of inferior vena cava diameter variability and lactic acid clearance in patients.To investigate the correlation between the variability of inferior vena cava diameter and lactic acid clearance after fluid resuscitation.Method1.Research object:A total of 54 patients with septic shock who underwent mechanical ventilation were selected from Liaocheng People's Hospital ICU ward between December 2015 to December 2016.2.Inclusion criteria and exclusion criteria:(1)Inclusion criteria:(1)age>18 years old.(2)According to the definition of sepsis 3.0,there is infection and sequential organ failure score(SOFA score)?2 points.(3)need to conduct mechanical ventilation treatment.(2)Exclusion criteria:(1)Intra-abdominal hypertension;(2)persistent arrhythmia(3)severe valvular disease;(4)body mass index(BMI)>40kg/m~2;(5)heart diversion or heart failure and other serious heart disease patients.3.Grouping:For all patients enrolled through active fluid resuscitation,the following objectives are required within 6 hours:1.CVP 8-12mmHg 2.MAP?65mmHg 3.Urine output?0.5ml/kg/h.Patients were divided into standard group(39 cases)and non-compliance group(15 cases)according to whether the standard was reached.4.Observation indicators:(1)The general information of the patients who were in groups;(2)The initial vital signs of the patient;(3)The variation of the diameter of the inferior vena cava and the index of arterial blood lactate in all the patients;(4)After 6 hours of fluid resuscitation,the variation of the diameter of inferior vena cava and the index of arterial blood lactate,and calculate the 6-hour lactate clearance of the patients.5.statistical analysis:All data were analyzed by SPSS 21.0 software,in the group,comparison of each index before and after fluid replacement test using paired t test,comparison between groups using independent sample t test,Pearson correlation analysis was used to analyze the correlation between indexes.The difference was statistically significant by P<0.05.The correlation between lactate clearance rate and the diameter of inferior vena cava was analyzed and the regression equation was calculated.The ROC curve of lactic acid clearance rate and the variation of inferior vena cava diameter was drawn,and the area of the two indexes under the curve was determined.Result1.Inferior vena cava diameter variability comparison of two groups of patients before and after resuscitation,the standard group of patients after resuscitation of inferior vena cava diameter variability was significantly lower than the initial value,there were significant differences between two groups(P<0.05),did not meet the patients after resuscitation of inferior vena cava diameter variability compared with the initial value is lower,but the difference was not statistically significant between the two indexes(P>0.05).2.Two groups of patients before and after fluid resuscitation of lactic acid value,lactic acid value standard group after resuscitation was significantly lower than its initial value(P<0.05),lactate group after resuscitation was lower than its initial value is not standard(P<0.05).3.After fluid resuscitation,the difference of the diameter of the inferior vena cava between the standard group and the non standard group was compared.The difference of the diameter of the inferior vena cava was significantly lower than the index of the standard group(P<0.05).4.After the resuscitation,the lactic acid clearance rate between the standard group and the non-compliance group was significantly higher than that of the untreated group(P<0.05).5.For fluid resuscitation in patients with standard inferior vena cava diameter variability and lactate clearance rate were analyzed,two indicators have relevance in Statistics(P<0.05),the regression equation is:the lactate clearance rate=-0.854×inferior vena cava diameter variability+40.293.6.By drawing up patients after fluid resuscitation of the inferior vena cava diameter variability and lactate clearance rate ROC curve analysis,the use of inferior vena cava diameter variability judgment in patients with septic shock fluid resuscitation is up to the standard,the area under the curve was 0.827.When the critical value was 25.66%,the sensitivity was 93.3%and the specificity was about 69.2%.The lactate clearance rate was used to determine whether the fluid resuscitation of septic shock patients reached the standard,and the area under the curve was 0.765.When the critical value was 18.36%,the sensitivity was 73.3%and the specificity was about 76.9%.Conclusion1.In patients with septic shock,the diameter of inferior vena cava was decreased after fluid resuscitation.And the liquid resuscitation to meet the standard patient indicators decreased more significantly.2.Liquid resuscitation to standard patients with lactate clearance was significantly higher than fluid resuscitation did not meet the standard of patients.3.There was a significant correlation between the changes of inferior vena cava diameter variability and the 6 hours lactate clearance rate after resuscitation,which could be used as an index to evaluate the hemodynamics in patients with septic shock.4.Monitoring the inferior vena cava diameter variability and 6-hour lactic acid clearance in patients with septic shock by bedside ultrasound,can accurately assess the patient's capacity reactivity.