Zhang H, et al. - In this study, experts wanted to discover how intradialytic central venous oxygen saturation (ScvO2) changes associate with ultrafiltration volume (UFV). This study unearthed a link between higher corrected for body weight (cUFV) volumes and steeper intradialytic ScvO2 drops, in most patients. It was presumed that in a majority of patients the intradialytic cardiac function was fluid dependent so that in the face of high ultrafiltration rates or volume, cardiac pre-load and consequently cardiac output decreased. They proposed the need for direct measurements of cardiac hemodynamics to further test this hypothesis.