National Research University of Electronic Technology Department of

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National Research University of Electronic Technology Department of biomedical systems Bazaev Nikolai Concepts of

National Research University of Electronic Technology Department of biomedical systems Bazaev Nikolai Concepts of wearable artificial kidney development London, 2017 1

Agenda • Why WAK and what it should be like? • Methods of blood

Agenda • Why WAK and what it should be like? • Methods of blood clearing • Methods of dialysis fluid regeneration • WAK SDR-01 and its trials 2

Wearable Artificial Kidney Enhancement of hemodialysis machines and quality of HD procedure Miniaturization of

Wearable Artificial Kidney Enhancement of hemodialysis machines and quality of HD procedure Miniaturization of HD machines (for home daily dialysis) Development of wearable artificial kidney 3

Advantages of Wearable Artificial Kidney Parameter Physiology criteria WAK related Low-flow prolonged dialysis (24/7)

Advantages of Wearable Artificial Kidney Parameter Physiology criteria WAK related Low-flow prolonged dialysis (24/7) Impact on organism is not intensive HD PD Lasts 3 -5 hours 3 times a week Impact on organism is intensive Last 4 -6 hours 4 times a day Impact on organism is not intensive Mobility Unrestricted mobility Restricted mobility Water consumption 2 -6 l per 3 days 24 l per 3 days 150 l per 3 days Quality of life High Low Costs 50 000 €/year/patient 60 000 €/year/patient 80 000 €/year/patient 4

Ideal Wearable Artificial Kidney ü Safety üBiocompatibility üEase of use üReliability üAvailability üContinuous power

Ideal Wearable Artificial Kidney ü Safety üBiocompatibility üEase of use üReliability üAvailability üContinuous power supply üPortability or implantability üLimited mechanical noise üElimination of molecular weight solutes similar to kidney function 5

Agenda • Why WAK and what it should be like? • Methods of blood

Agenda • Why WAK and what it should be like? • Methods of blood clearing • Methods of dialysis fluid regeneration • WAK SDR-01 and its trials 6

Hemodialysis VS Peritoneal dialysis What method to choose? 7

Hemodialysis VS Peritoneal dialysis What method to choose? 7

Waste dialysis fluid regeneration Clinical tasks of wearable artificial kidney: ― ions concentration stabilization

Waste dialysis fluid regeneration Clinical tasks of wearable artificial kidney: ― ions concentration stabilization in organism ― blood purification from small-, middle- and high-molecular substances ― stabilization of fluid balance 8

Hemodialysis VS Peritoneal dialysis Parameter WAK on HD WAK on PD Preference Massdimensional characteristics

Hemodialysis VS Peritoneal dialysis Parameter WAK on HD WAK on PD Preference Massdimensional characteristics 2. 5 -4 kg Bag with a pelvic belt or shoulder strap Equal Application Short daily and nocturnal home hemodialysis 2. 5 -4 kg Bag with a pelvic belt or shoulder strap Dialysis at home and at work, nocturnal dialysis. 24/7 dialysis Small-, middle- and high-molecular substances Peritoneum infection PD Weight of substances elimination Risks of infection Patient’s quality of life (Kidney Disease Quality of Life Instrument) Small- and middle- molecular substances Blood infection <1 year 43. 5 out of 100 48. 0 out of 100 1 -5 years 47. 5 out of 100 51. 2 out of 100 5 -10 years 41. 4 out of 100 45. 3 out of 100 PD PD PD 9

Agenda • Why WAK and what it should be like? • Methods of blood

Agenda • Why WAK and what it should be like? • Methods of blood clearing • Methods of dialysis fluid regeneration • WAK SDR-01 and its trials 10

Comparison of regeneration methods Regeneration unit Sorption ○ activated carbons ○ ion-change resins ○

Comparison of regeneration methods Regeneration unit Sorption ○ activated carbons ○ ion-change resins ○ foam carbon Electrolysis Catalysis of urea hydrolysis ○ Carbon based ○ Urease composite materials ○ Immobilized urease ○ Pt/Ti, Rh/Ti, Ru/Ti - electrodes ○ Ni-Co electrodes ○ etc. Thermal ○ heating elements ○ cooling elements Combination of methods for used dialysis regeneration How to eliminate urea from waste dialysis fluid? 11

Sorption 200 800 Uric acid concentration, mkmoles/l Creatine concentration, mkmoles/l 900 700 600 500

Sorption 200 800 Uric acid concentration, mkmoles/l Creatine concentration, mkmoles/l 900 700 600 500 400 300 200 100 0 0 2 4 6 Time, h 8 10 12 14 180 160 140 120 100 80 60 40 20 0 0 2 4 6 Time, h 8 10 12 14 12

Catalysis of urea hydrolysis 13

Catalysis of urea hydrolysis 13

Catalysis of urea hydrolysis Weak points of immobilized urease: 1. Very difficult to store

Catalysis of urea hydrolysis Weak points of immobilized urease: 1. Very difficult to store 2. Expensive 3. Necessity in zirconium phosphate (very expensive + high hydraulic pressure) p. H t=0 t=4 t=0 t=4 5, 11 8, 25 0, 07 1, 04 134, 0 131, 2 100, 8 111, 6 1, 194 0, 151 14

Thermal method p. H t=0 t=3 t=0 t=3 5, 1 6, 296 0, 06

Thermal method p. H t=0 t=3 t=0 t=3 5, 1 6, 296 0, 06 0, 79 129, 1 269, 1 98, 1 209, 5 1, 136 1, 383 15

Electrolysis 16

Electrolysis 16

Comparison of urea elimination methods Criteria Complexity of WAK development Consumption of electricity Mass-dimensional

Comparison of urea elimination methods Criteria Complexity of WAK development Consumption of electricity Mass-dimensional characteristics of WAK Necessity in expendable materials Price of expendable materials Time of cycle for expendable materials Complexity of expendable materials storage Thermal method Enzymatic method Electrolysis High Low Acceptable High (~5 k. W) Low (~7 W) Acceptable (~20 W) High (~70× 100 cm) Low (~30× 40 cm) Acceptable (~35× 55 cm) No Yes – 100 €/day 10 €/day – 6 -12 h – High (enzyme degrades during several days) 2 years for electrolyser +12 h for sorption units Low (in normal conditions can be stored unlimitedly) 17

Agenda • Why WAK and what it should be like? • Methods of blood

Agenda • Why WAK and what it should be like? • Methods of blood clearing • Methods of dialysis fluid regeneration • WAK SDR-01 and its trials 18

Wearable Artificial Kidney SDR-01 19

Wearable Artificial Kidney SDR-01 19

Wearable Artificial Kidney SDR-01 20

Wearable Artificial Kidney SDR-01 20

Laboratory test results of SDR-01 21

Laboratory test results of SDR-01 21

Laboratory test results of SDR-01 22

Laboratory test results of SDR-01 22

Results of animal trials of SDR-01 23

Results of animal trials of SDR-01 23

Results of animal trials of SDR-01 24

Results of animal trials of SDR-01 24

Where are we now 25

Where are we now 25

Problems to solve ØNecessity in continuous adding of osmotic agent or even better developing

Problems to solve ØNecessity in continuous adding of osmotic agent or even better developing of a brand new osmotic agent ØContinuous PD Catheter development ØRelatively high complexity for patients ØAbsence of standards for WAK ØClinical aspects of WAK usage ØPeritoneal membrane degradation ØAnimal trials 26