Figure 6From: Using heart-lung interactions to assess fluid responsiveness during mechanical ventilationRelationship between the respiratory changes in pulse pressure before volume expansion (Baseline ΔPP) and the volume expansion-induced changes in cardiac index (y-axis) in 40 septic patients with acute circulatory failure. The higher ΔPP is before volume expansion, the more marked the increase in cardiac index induced by volume expansion. Adapted with permission [7].Back to article page