The Evaluation Value Of Diaphragm Activity And Carbon Monoxide Diffusion Ability On The Severity Of Airflow Restriction In Patients With Chronic Obstructive Pulmonary Disease

ObjectiveTo evaluate the correlation between diaphragmatic activity(DE)and the percentage of carbon monoxide dispersion to the predicted value(DLCO%pred)and the degree of airflow limitation in patients with COPD,and to explore their predictive value for the severity of airflow limitation in patients with COPD,so as to realize multidimensional evaluation of patients with COPD,and identify the risk factors and risk of delayed deterioration in patients with COPD.And provide clinical basis for early detection of COPD in the elderly.MethodsA total of 206 patients with COPD acute exacerbation who completed diaphragm ultrasonography and lung function examination in our hospital from December 2020 to December 2022 were selected.Gender,age,height,weight,FEV1%pred,FEV1/FVC,FEV1,FVC,DE(diaphragm activity),DTF(diaphragm thickening fraction),DLCO(carbon monoxide dispersion),DLCO%pred(carbon monoxide dispersion as a percentage of the expected value),and IC(deep inspiratory volume)were collected.Participants were divided into mild,moderate,severe,and extremely severe groups(GOLDI-Ⅳ)according to the Global Initiative for Chronic Obstructive Pulmonary Disease(COPD)FEV1%pred airflow limitation scale.The differences of diaphragmatic activity,diaphragmatic thickening fraction,DLCO%pred and pulmonary ventilation function in COPD patients with different GOLD grades were compared.Spearman correlation analysis and ordered Logistic regression analysis were used to analyze the relationship between diaphragmatic parameters,DLCO%pred and pulmonary function.Diaphragmatic activity,DLCO%pred and FEV1%pred were included in the ROC curve to test the predictive value of diaphragmatic activity and DLCO%pred on the severity of COPD airflow restriction.P<0.05 indicated that the difference was statistically significant.Results1.There were no significant differences in sex ratio,age,BMI and lung volume among COPD patients with different GOLD grades(P>0.05).2.Pairwise comparison of IC,DLCO and DLCD%pred in groups GOLD Ⅰ,GOLD Ⅱ,GOLDⅢ and GOLD Ⅳ had statistical significance(P<0.05).IC,DLCO and DLCD%pred of patients decreased with the increase of GOLD grade.3.Pairwise comparison of diaphragmatic activity among groups GOLD Ⅰ,GOLD Ⅱ,GOLD Ⅲ and GOLD Ⅳ showed statistically significant differences(P<0.05),and the diaphragmatic activity of patients decreased with the increase of GOLD grade(see Figure 3-1).There was statistical significance in the scores of diaphragm thickening in GOLD Ⅰ,GOLD Ⅱ and GOLD Ⅳ groups(P<0.05),but there was no statistical significance in the scores of diaphragm thickening in other groups(P>0.05).4.There was a significant positive correlation between FEV1%pred and diaphragm activity,diaphragm thickening fraction and DLCO%pred(P<0.05),and the correlation between diaphragm activity and FEV1%pred was the highest(r=0.858),while the correlation between diaphragm thickening fraction and FEV1%pred was low(r=0.225).5.Gender,BMI and lung volume were not correlated with COPD severity.DLCO%pred and diaphragmatic activity were independent risk factors for COPD severity,and were negatively correlated with the severity of COPD,that is,the severity of COPD increased with the decrease of diaphragmatic activity and DLCO%pred.6.Muscle activity and DLCO%pred were used as test variables,and ROC curve was drawn(Figure 3-3,3-4).The results showed that diaphragmal activity and DLCO%pred predicted that FEV1%pred≥50%and FEV1%pred≥30%AUC(area under ROC curve)of patients with COPD were all greater than 0.8.With high predictive value(see Figure 3-3,3-4),the sensitivity of DLCO%pred and diaphragm activity to predict FEV1%pred≥50%was 92.2%and 98.7%,respectively(see Table 3-6).The sensitivities of DLCO%pred and diaphragm activity to predict FEV1%pred≥30%were 94.1%and 97.8%,respectively(see Table 3-7),and the difference was statistically significant(P<0.05).Conclusion1.With the increase of GOLD grading,DLCO and DLCD%pred in COPD patients showed a gradual downward trend.2.With the increase of GOLD grade,diaphragm activity in COPD patients showed a gradual decline.3.Diaphragmatic activity and DLCD%pred are independent risk factors for the severity of pulmonary airflow restriction in COPD patients4.Diaphragmatic activity and DLCO%pred have a good predictive value for the severity of airflow restriction in COPD patients.