Predictive Value Of Volume Load Monitoring Based On BIA Combined With Ultrafiltration Volume/Dry Weight For Frequent-intradialytic Hypotension

Objective To explore the predictive value of volume load based on bioelectrical impedance analysis(BIA)and ultrafiltration volume/dry weight for frequent-intradialytic hypotension(f-IDH)in hemodialysis(HD)patients,and whether the combination of the two can improve the predictive value for f-IDH.Methods HD patients who were admitted to Hangzhou Hospital of Traditional Chinese Medicine affiliated to Zhejiang Chinese Medicine University from January 2021 to April 2021 were selected as subjects.General data,laboratory indicators,urea clearance index(Kt/V),24h urine volume,echocardiographic data,ultrafiltration volume/dry weight of the patients were collected.And the volume load indicators,namely overhydration(OH)and extracellular water(ECW),were measured by body composition monitor.The relative fluid overload(RFO)was calculated to evaluate the volume load status of patients,in which RFO=OH/ECW.To diagnose patients with f-IDH according to whether the frequency of intradialytic hypotension(IDH)within one month is≥ 20%.After all data were sorted out,single factor analysis was performed using t-test,Mann-whitney U test and χ2 test by SPSS26.0 to compare the difference of each indicator between groups.Using the receiver operating characteristic(ROC)curve to evaluate the predictive values of OH/ECW and ultrafiltration volume/dry weight for f-IDH and to calculate their best cutoff values.According to the best cutoff value of OH/ECW,the patients were divided into two groups:high OH/ECW group and low OH/ECW group.According to the best cutoff value of ultrafiltration volume/dry weight,the patients were divided into two groups:high ultrafiltration volume/dry weight group and low ultrafiltration volume/dry weight group.The prevalence of f-IDH between the two groups was respectively compared.With f-IDH as dependent variable and the meaningful indicators of univariate analysis as independent variables(OH/ECW and ultrafiltration volume/dry weight were converted into binary variables according to the best cut-off value),logistic regression analysis was performed to analysis the relationship among OH/ECW,ultrafiltration volume/dry weight with f-IDH.The predictive value of OH/ECW combined with ultrafiltration volume/dry weight for f-IDH was evaluated by ROC.Eventually,the OH/ECW and ultrafiltration volume/dry weight were divided into four groups.Group A:high OH/ECW and high ultrafiltration volume/dry weight,Group B:high OH/ECW and low ultrafiltration volume/dry weight,Group C:low OH/ECW and high ultrafiltration volume/dry body weight,Group D:low OH/ECW and low ultrafiltration volume/dry body weight,then the total prevalence of f-IDH among the four groups were compared.Results A total of 324 patients were enrolled,101 of whom were complicated with f-IDH,and the prevalence of f-IDH was 31.17%.Uni variate analysis revealed that the proportion of diabetes mellitus,the contents of total cholesterol and triglyceride,Kt/V,ultrafiltration volume/dry weight in f-IDH patients were significantly higher than those in non-f-IDH patients,while the proportion of the male and anuria,serum creatinine and OH/ECW were significantly lower than those in non-f-IDH patients.The ROC analysis revealed that the area under the curve(AUC)of OH/ECW for diagnosis of f-IDH was 0.660.When the cutoff value of OH/ECW was 11.17%,the sensitivity was 0.624,and the specificity was 0.668.After grouping according to the best cutoff value of OH/ECW,it was found that the prevalence of f-IDH in high OH/ECW group was lower than that in low OH/ECW group,and the difference was statistically significant.The ROC analysis revealed that the AUC of ultrafiltration volume/dry body for diagnosis of f-IDH was 0.613.When the cutoff value of ultrafiltration volume/dry body was 2.97%,the sensitivity was 0.653,and the specificity was 0.552.After grouping according to the best cutoff value of ultrafiltration volume/dry body,it was found that the prevalence of f-IDH in high ultrafiltration volume/dry body group was higher than that in low ultrafiltration volume/dry body group,and the difference was statistically significant.OH/ECW and ultrafiltration volume/dry weight were converted into binary variables according to the best cutoff value,then multivariate logistic regression analysis was carried out.The results showed that diabetes mellitus、Kt/V and ultrafiltration volume/dry weight≥ 2.97%were risk factors of f-IDH in HD patients.Male and OH/ECW≥11.17%were protective factors of f-IDH in HD patients.The ROC analysis revealed that the AUC of OH/ECW combined with ultrafiltration volume/dry body for diagnosis of f-IDH was 0.762,the sensitivity was 0.842,and the specificity was 0.520.There was significant difference in the prevalence of f-IDH among group A,B,C and D(χ2=27.941,P<0.001).After pairwise comparison,it was found that the prevalence of f-IDH in group C was the highest among the four groups,and there was significant difference compared with group A,group B and group D(P<0.008).Conclusion OH/ECW,ultrafiltration volume/dry body weight can be used as predictors of f-IDH in HD patients,but the predictive efficiency was low alone.OH/ECW combined with ultrafiltration volume/dry body weight can further improve the predictive value of f-IDH in HD patients to some extent.