Short term variability of oxygen saturation during hemodialysis is a warning parameter for hypotension appearance

Acute hypotension is a frequent complication of hemodialysis. Blood oxygenation may play a role in hypotension and hypoxemia may be considered as a surrogate marker of hemodynamic instability. Continuous, non-invasive monitoring of oxygen saturation (SO₂) during hemodialysis is now possible, by means of sensors measuring SO₂ in blood entering the dialyzer. The aim of the present work was to analyze the short-term variability of SO₂ during hemodialysis in sessions with and without hypotension to correlate the SO₂ variability to hemodynamic instability. Our preliminary results showed an interesting, yet to be fully understood, role of SO₂ in anticipating hypotension onset.