• 4h hemodialysis session using standard polysulphone dialyzer and Nikkiso dialysis monitors
• Minimal dose of unfractionated heparin (UFH) with loading dose 500IE and maintenance 500IE/h, stopped 60 minutes before session end in case of AVF use.
• Standard bicarbonate-based ultrapure dialysate. Na, K, Ca, bicarbonate concentrations according to the patient's routine dialysis prescription.
• The blood flow rate maximized as per routine nursing care.
• Dialysate flow rate fixed at 500 ml/min.
• Dialysate temperature between 35.5°C and 36.5°C.
• Ultrafiltration according to patient's dry weight and supported ultrafiltration rate.
• At the end of the dialysis session the blood will be returned (100ml/min) to the patient.

Blood sample at start and at the end of the dialysis session; membrane scoring after dialysis; total cell volume measurement of dialyzer after dialysis; micro-CT of dialyzer after dialysis.

thrombin antithrombin complex levels (mcg/L). Samples for TAT measurement were taken during the single hemodialysis study treatment. All patients underwent their study treatments between October - December 2018. All analyses were performed in batch in January 2019.

number of open fibers of dialyzer counted after microCT scanning of dialyzer membrane. Dialyzers were collected after the hemodialysis study treatment. All patients underwent their study treatments between October - December 2018. All micro CT scans were performed using the same scanner in Fabruary and March 2019.