Fig. 3. (  A ) Correlation plot showing the relation between end-diastolic blood volume (GEDV) and measured intrathoracic blood volume (ITBV^m) in the control group (ITBV^m= 1.21 × GEDV + 99;  r ²= 0.89,  P < 0.0001; 95% confidence interval [CI] for slope, 1.1–1.4 and 95% CI for y-intercept, 31–168). (  B ) Shock group under normovolemic (  open triangles and squares with the correlation line shown as  interrupted line : ITBV^m= 1.3 × GEDV + 58;  r ²= 0.92,  P < 0.0001; 95% CI for slope, 1.1 to 1.5 and 95% CI for y-intercept, −33 to 150) and hypovolemic conditions (  shaded triangles and squares with the correlation line shown as a  solid line : ITBV^m= 1.45 × GEDV + 0.6;  r ²= 0.95,  P < 0.0001; 95% CI for slope, 1.3 to 1.6 and 95% CI for y-intercept, −47 to 49). The differences between the slopes and intercepts of the three equations are not statistically significant.