Volume 53, Issue 4, Pages 1036-1043 (April 1998) Identification of operational clues to dry weight prescription in hemodialysis using bioimpedance vector analysis  Antonio Piccoli, for the Italian Hemodialysis-Bioelectrical Impedance Analysis (HD-BIA) Study Group  Kidney International  Volume 53, Issue 4, Pages 1036-1043 (April 1998) DOI: 10.1111/j.1523-1755.1998.00843.x Copyright © 1998 International Society of Nephrology Terms and Conditions

Figure 1 RXc mean graph, with the mean vectors (arrows) and the 95% confidence ellipses for men and women from the three classification groups: healthy control subjects (dotted ellipse), stable hemodialysis patients (line dashed ellipse) and unstable hemodialysis patients (hatched ellipse). Abbreviations are: R, resistance; Xc, reactance; H, height. Kidney International 1998 53, 1036-1043DOI: (10.1111/j.1523-1755.1998.00843.x) Copyright © 1998 International Society of Nephrology Terms and Conditions

Figure 2 Dotted ellipses represent the distribution of 50% impedance vectors from individual HD stable patients before (lower ellipse) and after fluid removal (upper ellipse). Doubled headed arrows represent the vector cycling of the average stable patient before (center of the lower dotted ellipse) and after HD (center of the upper ellipse). Dotted ellipses are plotted over the reference, gender-specific, 50%, 75% and 95% tolerance ellipses of the healthy population. Using the scale of the Figure for R/H and Xc/H, we drew ellipses with the major and minor axes’ slopes of 69.30° and -20.70°, respectively, in the men's panel, and of 69.27° and -20.73° in the women's panel. The semi-axis lengths of the men panel ellipses were 89 and 43 Ohm/m for the 50% tolerance, 127 and 61 Ohm/m for the 75% tolerance, and 187 and 89 Ohm/m for the 95% tolerance ellipses. In the women's panel ellipses, the semi-axis lengths were 95 and 50 Ohm/m for the 50% tolerance, 135 and 71 Ohm/m for the 75% tolerance, and 199 and 105 Ohm/m for the 95% tolerance12. Abbreviations are: R, resistance; Xc, reactance; H, height. Kidney International 1998 53, 1036-1043DOI: (10.1111/j.1523-1755.1998.00843.x) Copyright © 1998 International Society of Nephrology Terms and Conditions

Figure 3 Dotted ellipses represent the distribution of 50% impedance vectors from unstable individual hemodialysis patients before (lower ellipse) and after fluid removal (upper ellipse). Symbols and reference tolerance ellipses were drawn as in Figure 2. Kidney International 1998 53, 1036-1043DOI: (10.1111/j.1523-1755.1998.00843.x) Copyright © 1998 International Society of Nephrology Terms and Conditions

Figure 4 A phase angle with the critical prognostic value of 4.5° obtained from literature, is depicted on data from male healthy subjects, and renal and AIDS patients. Small hatched ellipses are the 95% confidence ellipses of mean vectors from healthy subjects and hemodialysis patients as in Figure 1. The open ellipse is the 95% confidence ellipse of the mean vector from 25 renal patients with apparent edema not undergoing dialysis treatment, and described elsewhere22. Vectors indicated by broken arrows a to e are the mean vectors from 75 AIDS patients (Caucasian adult males) whose estimated survival after 30 months was 90%, 80%, 50%, 15%, and 3%, respectively20. Hemodialysis patients with vector phase angles smaller than 4.5° had a two-year survival that was worse than patients with steeper vectors either in the Caucasian population (postdialysis, lower quartile phase angle)18 or in a multiracial American population (predialysis, lowest two quintile phase angle)19. Kidney International 1998 53, 1036-1043DOI: (10.1111/j.1523-1755.1998.00843.x) Copyright © 1998 International Society of Nephrology Terms and Conditions