Zhang H, et al. - In this retrospective study, researchers tested if central venous oxygen saturation (ScvO₂) variability is associated with all-cause mortality in chronic hemodialysis (HD) patients. They recorded ScvO₂ 1× per minute during dialysis using the Crit-Line monitor for 232 chronic HD patients with central venous catheter as vascular access. In this study, a 6-month baseline comprising at least 10 dialysis treatments with ScvO₂ recordings preceded a follow-up period of up to 3 years. Outcomes revealed increased all-cause mortality in relation to high ScvO₂ variability during dialysis.