The Study On The Value Of Diaphragmatic Ultrasound Index Combined With Blood Lactate Difference In Predicting The Weaning

Objective:to investigate the predictive value of the difference between diaphragm ultrasound index and arterial blood lactic acid level before and after SBT test for the outcome of withdrawal,so as to provide reference for the choice of withdrawal time in patients with mechanical ventilation.Methods:from January 2019 to February 2020,patients who underwent invasive mechanical ventilation in emergency EICU of Hunan people' s Hospital were selected as the subjects of observation group and included in this study.A total of 62 cases met the inclusion and excretion criteria.According to the final withdrawal outcome,they were divided into two groups:withdrawal success group and withdrawal failure group.The general data,hospitalization,prognosis,respiratory indexes before and after withdrawal,diaphragmatic displacement(DD),spontaneous respiratory frequency(RR),tidal volume(VT),shallow respiratory index(RSBI)and diaphragm superficial respiratory index were collected and compared between the two groups.(the level of blood lactic acid before and after D-RSBI),SBT test was used to find out the related factors affecting the outcome of withdrawal by single factor analysis and multivariate analysis,and the factors found out were regarded as the reference indexes with potential prediction value,and the prediction value of each index to the outcome of withdrawal was evaluated by ROC curve analysis.Results:(1)There was no significant difference in age,gender,body mass index,smoking and alcohol history,primary disease,combined disease and APACHE-II score between the two groups(P>0.05).(2)There was no significant difference in pH,HR,RR,PaC02,Pa02,Sp02 and map between the two groups before the weaning(P>0.05).(3)There was no significant difference in mortality between the two groups(P>0.05).(4)There was no significant difference in(RR),tidal volume between the two groups(P>0.05),but the mean diaphragm mobility(DD)in the failed group was significantly lower than that in the successful group(P>0.05),but there was no significant difference in the mortality between the two groups(P>0.05),but the mean phrenic mobility of the patients in the failed group was significantly lower than that in the successful group.However,(RSBI)and phrenic shallow fast respiration index were higher than those in the successful group(P<0.05).(5)The level of blood lactic acid in the group with failed SBT was slightly higher than that in the group with successful withdrawal,but the difference was not significant.At the end of SBT test,the level of blood lactic acid in most patients with failed withdrawal was significantly higher than that before the test,and was significantly higher than that in the successful group(P<0.05).(6)There were significant differences between the two groups in the mean diaphragmatic displacement(DD),shallow fast respiratory index(RSBI),arterial blood lactic acid level after SBT test and difference of blood lactic acid level before and after SBT test.The difference of blood lactic acid level between the two groups before and after SBT test was further compared(P<0.05).(7)Multivariate logistic regression analysis showed that the mean diaphragmatic displacement(DD)was small,shallow fast respiratory index(RSBI)was high,and the diaphragm shallow fast respiratory index was high,The high difference of blood lactic acid level before and after SBT test was an independent risk factor for the failure of withdrawal(P<0.05).Conclusion:The difference of blood lactate level before and after SBT test and phrenic superficial fast breathing index were combined to evaluate the predictive sensitivity and specificity of the outcome of weaning.When the two indexes were used separately,they were also higher than the traditional indexes such as superficial fast breathing index,which can better guide the practice of weaning and is worthy of clinical promotion.