Fluid removal (ultrafiltration) during dialysis
A patient’s tolerance to dialysis and ultrafiltration is more easily accepted when performes separately, but as this would double the treatment time a compromise is necessary.
During dialysis, fluid can only be removed from the vascular compartment. The facilitates slower re-filling from the extra-vascular compartment. In order to prevent precipitation of hypotension, which would occur whan fluid removal from the vascular compartement exceeds the ability of the physiological compensatory respons, and is associated with changes in myocardial blood supply and poor outcomes.