Recommended
More Related Content
Similar to principles of dialysis 2019.pptx
Similar to principles of dialysis 2019.pptx (20)
Recently uploaded
Recently uploaded (20)
principles of dialysis 2019.pptx
- 1. PRINCIPLES OF DIALYSIS Dr. Arun Varghese T Nephrologist Siva Hospital
- 4. • High efficiency vs low efficiency • High flux vs low flux • KoA, Kuf • Isolated ultrafiltration/Sequential dialysis • Hemodiafiltration • Hemofiltration
- 5. Functions of the Kidneys • Excretory – Excretion of waste products • Regulatory – Fluid – Electrolytes – Acid base • Hormonal – Rennin – Erythropoietin – 1,25 OH D3 • Metabolic
- 6. Functions of the Kidneys • Excretory • Regulatory – Electrolytes – Acid base – Fluid • Hormonal – Renin – Erythropoiten – 1,25 OH D3 • Metabolic Solute removal or solute shift Water removal
- 10. Functions of the Kidneys • Excretory • Regulatory – Electrolytes – Acid base – Fluid • Hormonal – Renin – Erythropoiten – 1,25 OH D3 • Metabolic Solute removal or solute shift Water removal
- 11. Functions of the Kidneys • Excretory • Regulatory – Electrolytes – Acid base – Fluid • Hormonal – Renin – Erythropoiten – 1,25 OH D3 • Metabolic Solute removal or solute shift Water removal diffusion ultrafiltration
- 12. • Solution • Semipermeable membrane
- 13. • Solution –mixture of solvent and solute In dialysis • Treated water- solvent • Electrolytes and glucose – solute • Solubility
- 14. • Membrane – thin layer of tissue
- 16. What is Diffusion ? • Movement of the solute through semi permeable membrane from one side to the other on the basis of concentration gradient
- 17. Diffusion – Random Molecule Movement `
- 18. Diffusion – Random Molecule Movement `
- 19. Diffusion – Random Molecule Movement `
- 20. Diffusion – Random Molecule Movement `
- 21. • example
- 22. • Tea bag
- 23. Functions of the Kidneys • Excretory • Regulatory – Electrolytes – Acid base – Fluid • Hormonal – Renin – Erythropoiten – 1,25 OH D3 • Metabolic Solute removal or solute shift Water removal diffusion ultrafiltration
- 25. • Movement of fluid (solvent) across the membrane • Controlled fluid removal by manipulation of pressure
- 26. • Filtration occure when fluid is pushed through hydraulic pressure • Fluid always moves from higher pressure to a lower one
- 29. Basic Principals of Dialysis • Principles related to solute removal – Diffusion – Convection – ( KoA) • Principles related to water removal – Ultrafiltration – Osmosis – (Ultrafiltration coefficient-KUF)
- 31. • Convection is transfer of solutes by physical circulation of a liquid
- 32. • Example
- 35. Movement of FLUID across a semipermeable from an area of LOWER solute concentration to an area of HIGHER solute concentration.
- 36. • In diffusion- solutes move • In osmosis – solvent moves
- 37. • Application in Dialysis
- 39. • How to measure diffusion? • KoA
- 40. • What are the factors determining diffusion?
- 41. MW of solute Pore size Pore number & distribution Membrane thickness Membrane surface area Temperature on either side Concentration gradient
- 42. Diffusion in dialysis MW of solute Pore size Pore number & distribution Membrane thickness Membrane surface area – A Temperature on either side Concentration gradient Ko
- 43. KoA • The theoretical maximum clearance of the dialyzer at infinite dialysate and blood flow • Ko- permeability coefficient of the dialyzer • A - surface area • Expressed in ml/min
- 44. Mass transfer area coefficient KoA Diffusive resistance `
- 45. • Efficacy • Related to urea clearance of dialyzer urea clearance – KoAurea – Low efficacy – KoAurea < 500 ml/min – High efficacy – KoAurea > 600 ml/min
- 46. Diffusion in Dialyzer For adequate diffusion Dialysate flow 2-2.5 time blood flow
- 47. Effect of Blood Flow on Clearance
- 49. Distribution of pore size A B
- 52. • What are the factors determining ultrafiltration?
- 53. • Trans membrane pressure • Hydraulic permeability of the membrane
- 54. ULTRAFILTRATION Controlled fluid removal by manipulation of hydrostatic pressure. • Ultrafiltration uses both positive and negative pressure: o Positive pressure • pressure exerted by the blood flowing through the dialyzer, Results from blood being pushed by blood pump o Negative pressure • pressure applied to the dialysate side by the machine • Pulls excess fluid from blood compartment to dialysate compartment drain
- 57. Ultrafiltration Transmembrane pressure (TMP) = Positive pressure A - Negative pressure B A B
- 58. • Hydraulic permeability • Surface area • Number and size of por
- 59. Ultrafiltration Coefficient (KUF) • Milliliter of fluid per hour per mm Hg pressure difference across the membrane • Expressed in ml/hr/mmHg
- 60. • Flux – Measure of ultrfiltration capacity – Low or high flux dialyzers based on KUF
- 61. Low flux vs high flux – Low flux - KUF < 10 ml/hr/mmHg – High flux - KUF > 20 ml/hr/mmHg – Low flux - B2 microglobulin clearance < 10 ml/min – High flux - B2 microglobulin clearance > 20 ml/min
- 62. • Summarise
- 63. • High efficiency vs low efficiency • High flux vs low flux • KoA, Kuf • Isolated ultrafiltration/Sequential dialysis • Hemodiafiltration • Hemofiltration
- 64. RRTs – Principles of Dialysis Diffusion Convection Ultrafiltration Conventional Hemodialtsis +++ + + Hemofiltration - ++++ ++++ Hemodialfiltration +++ ++++ ++++
- 65. RRTs – Principles of Dialysis Diffusion Convection Ultrafiltration Conventional Hemodialtsis +++ + + High Efficiency HD ++++ + + High Flux Dialysis +++ +++ +++ Hemofiltration - ++++ ++++ Hemodialfiltration +++ ++++ ++++
- 66. 1 • The blood dialysate flow configuration that maintains the optimum blood dialysate concentration gradient A. Concurrent flow B. Countercurrent flow C. Crosscurrent flow D. Recirculation flow
- 67. 2 • Ultrafiltration during hemodialysis is due to A. Dialysate flow rate B. Blood flow rate C. Osmotic pressure gradient between blood and dialysate D. Hydrostatic pressure gradient between blood and dialysate E. None of above
- 68. 3 • Ultrafiltration coefficient (KUF) refers to A. The resistance to water removal B. Amount of water removed from blood per unit time as a function of pressure difference C. The amount of water removed per unit time D. The resistance of dialyzer to solute removal
- 69. 4 • Mass transfer coefficient refers to A. Amount of fluid removed per unit time B. Amount of solute removed per unit time C. The resistance offered to solute removal D. The resistance offered to fluid removal E. None of them
- 70. • Thank you
- 71. 5 • Sieving coefficient depends on all of following EXEPT A. Molecular weight cutoff the membrane B. Ultrafiltration rate C. Surface area D. Diffusion
- 73. Body water distribution • In dialysis water and solutes can be removed only from bloodstream
- 76. • Diffusion is greater for small molecules as compared to larger molecules • Low flux: molecular wt cut off = 10000 daltons • High flux: molecular weight cut off = 30000 daltons
- 77. RRTs – Principles of Dialysis Diffusion Convection Ultrafiltration Conventional Hemodialtsis +++ + + High Efficiency HD ++++ + + High Flux Dialysis +++ +++ +++ Hemofiltration - ++++ ++++ Hemodialfiltrat ion +++ ++++ ++++ Peritoneal Dialysis +++ - -
- 79. Measuring dialysis adequacy • Urea reduction ratio • Kt/V