Effects of Pre-Dialysis Fluid Overload, Intradialytic Relative Blood Volume Levels and Cumulative Ultrafiltration Volume on Pulse Wave-Derived Features during Hemodialysis: Results from a Longitudinal Cohort Study

Figures

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  Fig. 1.. Peripheral (measured) and central (estimated) arterial PWs with wave separation. a An exemplary 10-s recording of peripheral arterial pressure as measured by a brachial cuff. b The corresponding central PW transformed from the peripheral measurement with annotation of selected features. AIX, augmentation index; AP, augmentation pressure; CPP, central pulse pressure; p, pressure; Pb, amplitude of backward traveling PW.

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  Fig. 2.. Patient flowchart. Shown are the number of patients screened, interested, included, and finally analyzed in the present study. The present study was part of a larger trial investigating longitudinal FO and absolute blood volume in HD patients.

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  Fig. 3.. Forest plot of results from GEEs reporting standardized effects of RBV on PWFs. Shown are effect estimates (beta coefficients) per one percentage point change in RBV with 95% CIs and p values obtained with GEEs. Effects are expressed as percentages of SDs of the analyzed PWFs (z-scored). Some features (indicated using the dagger symbol, †) were nonlinearly transformed before the analysis, affecting in these cases direct interpretation of the effects in original units. Pre-transformation SDs of the analyzed features are shown under “pooled SD.” The coefficient of determination (R2) was calculated for the GEE including RBV as an independent variable. The drop in R2 (partial R2) when RBV was omitted from the GEE is shown as a percentage value in the rightmost column (a negative value indicates a better fit without RBV). All GEEs were adjusted for treatment time, age, sex, day of week, and trial phase. All p values were corrected for false discovery rate using the Benjamini-Hochberg procedure. 95% CI, 95% confidence interval.

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  Fig. 4.. Forest plot of results from GEEs reporting standardized effects of RBV on PWFs, adjusted for cUFV. Shown are effect estimates (beta coefficients) per one percentage point RBV with 95% CIs and p values obtained with GEEs, adjusted for cUFV. Effects are expressed as percentages of SDs of the analyzed PWFs (z-scored). Some features (indicated using the dagger symbol, †) were nonlinearly transformed before the analysis, affecting in these cases direct interpretation of the effects in original units. Pre-transformation SDs of the analyzed features are shown under “pooled SD.” The coefficient of determination (R2) was calculated for the GEE including RBV as an independent variable. The drop in R2 (partial R2) when RBV was omitted from the GEE is shown as a percentage value in the rightmost column (a negative value indicates a better fit without RBV). All GEEs were further adjusted for treatment time, age, sex, day of week, and trial phase. All p values were corrected for false discovery rate using the Benjamini-Hochberg procedure. 95% CI, 95% confidence interval.

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  Fig. 5.. Forest plot of results from GEEs reporting standardized effects of cUFV on PWFs. Shown are effect estimates (beta coefficients) per 100-mL cUFV with 95% CIs and p values obtained with GEEs. Effects are expressed as percentages of SDs of the analyzed PWFs (z-scored). Some features (indicated using the dagger symbol, †) were nonlinearly transformed before the analysis, affecting in these cases direct interpretation of the effects in original units. Pre-transformation SDs of the analyzed features are shown under “pooled SD.” The coefficient of determination (R2) was calculated for the GEE including cUFV as an independent variable. The drop in R2 (partial R2) when cUFV was omitted from the GEE is shown as a percentage value in the rightmost column (a negative value indicates a better fit without cUFV). All GEEs were adjusted for treatment time, age, sex, day of week, and trial phase. All p values were corrected for false discovery rate using the Benjamini-Hochberg procedure. 95% CI, 95% confidence interval.

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  Fig. 6.. Forest plot of results from GEEs reporting standardized effects of cUFV on PWFs, adjusted for RBV. Shown are effect estimates (beta coefficients) per 100-mL cUFV with 95% CIs and p values obtained with GEEs, adjusted for RBV. Effects are expressed as percentages of SDs of the analyzed PWFs (z-scored). Some features (indicated using the dagger symbol, †) were nonlinearly transformed before the analysis, affecting in these cases direct interpretation of the effects in original units. Pre-transformation SDs of the analyzed features are shown under “pooled SD.” The coefficient of determination (R2) was calculated for the GEE including cUFV as an independent variable. The drop in R2 (partial R2) when cUFV was omitted from the GEE is shown as a percentage value in the rightmost column (a negative value indicates a better fit without cUFV). All GEEs were further adjusted for treatment time, age, sex, day of week, and trial phase. All p values were corrected for false discovery rate using the Benjamini-Hochberg procedure. 95% CI, 95% confidence interval.