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Hemodialysis: History and Current Perspective Nadeem A Siddiqui MD Dallas Nephrology Associates Slide 2 Hemodialysis:History and Current Perspective History of Dialysis History of Dialysis Principles of Hemodialysis Principles of Hemodialysis Practice of Hemodialysis Practice of Hemodialysis Complications of Hemodialysis Complications of Hemodialysis Slide 3 Dialysis Process by which the solute composition of a solution A is altered by exposing it to a second solution B through a semi- permeable membrane Process by which the solute composition of a solution A is altered by exposing it to a second solution B through a semi- permeable membrane Slide 4 Slide 5 Necessary pre-requisites for Hemodialysis 1) Semi-permeable membrane 1) Semi-permeable membrane 2) Anticoagulation 2) Anticoagulation 3) Knowing what to remove and how much of it 3) Knowing what to remove and how much of it Slide 6 1773: Nurepuel isolates Urea by boiling urine in a pan 1773: Nurepuel isolates Urea by boiling urine in a pan Slide 7 1828: Wohler synthesizes Urea and describes its molecular structure 1828: Wohler synthesizes Urea and describes its molecular structure Slide 8 Thomas Graham (1805-1869) Slide 9 1850 Glasgow, Scotland: 1850 Glasgow, Scotland: Thomas Graham s experiment to demonstrate diffusion across a semi- permeable membrane (Pergamon paper) Thomas Graham s experiment to demonstrate diffusion across a semi- permeable membrane (Pergamon paper) Slide 10 Slide 11 Slide 12 Dialysis Membranes 1750:Advances in the dovelopment of smokeless gunpowder led to the synthesis of a strong Nitrocellulose called collodion. It was a combination of Nitric acid and cotton 1750:Advances in the dovelopment of smokeless gunpowder led to the synthesis of a strong Nitrocellulose called collodion. It was a combination of Nitric acid and cotton Addition of Camphor to this substance led to the synthesis of stable and strong plastics Addition of Camphor to this substance led to the synthesis of stable and strong plastics 1957:Helmut Staldiger polymerized Cellulose 1957:Helmut Staldiger polymerized Cellulose Slide 13 Slide 14 1913:The First Hemodialysis Experiment Slide 15 1937: William Thalhimer successfully lowers BUN by performing Hemodialysis in anephric dogs 1937: William Thalhimer successfully lowers BUN by performing Hemodialysis in anephric dogs Slide 16 1926:The First Human Experiment George Haas used a collodion tube arrangement to successfully dialyze human subjects George Haas used a collodion tube arrangement to successfully dialyze human subjects Allergic reactions to impurities in Hirudin led him to abandon his experiments Allergic reactions to impurities in Hirudin led him to abandon his experiments Slide 17 1937:Nils Alwall used the Alwall Kidney to perform the first ever hemodialysis treatment at the university of Lund, Sweden 1937:Nils Alwall used the Alwall Kidney to perform the first ever hemodialysis treatment at the university of Lund, Sweden Slide 18 Slide 19 If I have seen farther it is because I have stood on the shoulders of Giants Sir Isaac Newton Sir Isaac Newton Slide 20 Hemodialysis:History and Current Perspective History of Dialysis History of Dialysis Principles of Hemodialysis Principles of Hemodialysis Slide 21 Mechanisms of Solute transfer Diffusion Diffusion Convection Convection Slide 22 Diffusive Clearance A result of random molecular motion A result of random molecular motion Influenced by concentration gradient of the solute and its Molecular weight as well as by the membrane permeability to the solute Influenced by concentration gradient of the solute and its Molecular weight as well as by the membrane permeability to the solute Slide 23 Convective Clearance Water molecules passing through a SPM carry with them the solutes in their original concentration. This is called the solvent drag phenomenon Water molecules passing through a SPM carry with them the solutes in their original concentration. This is called the solvent drag phenomenon Water can be made to move across a SPM by the application of either a hydrostatic or an osmotic gradient Water can be made to move across a SPM by the application of either a hydrostatic or an osmotic gradient Slide 24 Slide 25 Slide 26 Hemodialysis:History and Current Perspective History of Dialysis History of Dialysis Principles of Hemodialysis Principles of Hemodialysis Practice of Hemodialysis Practice of Hemodialysis Slide 27 The Hemodialysis circuit Slide 28 Dialysis Membranes MembraneHydr.Perm.ExamplesBiocomp. Regen. cellulose Low flux cuprophanePoor Modif.Cellulose Low/High Flux Cell.acetate Cell di-acet. Interm. Synthetic High/Low flux PAN,PS,PA,PC,PMMCGood Slide 29 Dialysis Solution ComponentConcentrationmmol/L Na140 K2 Ca 1.25 (5 mg/dl) Mg 0.5 (1.2 mg/dl) Acetate3.0 Chloride108 Bicarbonate35 Glucose 5.6 (100 mg/dl) Slide 30 Water Purification Slide 31 Slide 32 Slide 33 Water Treatment System for Hemodialysis Slide 34 Vascular Access Slide 35 Slide 36 Slide 37 Slide 38 Slide 39 Slide 40 Slide 41 Slide 42 Slide 43 Indications for initiating Hemodialysis In patients with calculated creatinine clearanceSlide 44 Indications for Hemodialysis *Pericarditis or Tamponade (urgent indication) *Uremic platelet dysfunction (urgent indication) *Refractory volume overload *Refractory hyperkalemia *Refractory Metabolic acidosis with anuria Slide 45 Indications for Hemodialysis Steadily worsening renal function in a patient with measured 24 hour urinary creatinine clearance Slide 46 Equations for estimation of renal function Cockcroft and Gault equation Cockcroft and Gault equation MDRD Formula MDRD Formula Slide 47 The Cockcroft-Gault equation Cr Cl =(140-age) x wt/72(serum Cr) Cr Cl =(140-age) x wt/72(serum Cr) Decrease 15% for women Decrease 20% for paraplegia,40% for quadriplegia Increase 12% for AA males Slide 48 The MDRD formula Modification of diet in renal disease study JASN2000 GFR (ml/min/1.73m 2 )= GFR (ml/min/1.73m 2 )= 186 x Pcr -1.154 x age -0.203 x1.212 if black X0.742 if female 186 x Pcr -1.154 x age -0.203 x1.212 if black X0.742 if female The MDRD equation calculates GFR, hence values are lower than those of creatinine clearance by Cockcroft Gault equation. Slide 49 Measurement of nutritional status Physical Exam Physical Exam Skin fold thickness Skin fold thickness Mid arm muscle thickness Mid arm muscle thickness Protein catabolic rate 33 9. Use non Cellulosic membranes 10. Keep Dialysate temperature Slide 59 Neuromuscular Complications: Muscle Cramps Etiology: Hypo-osmolality, Carnitine deficiency, Hypomagnesemia, excessive inter-dialytic weight gain Etiology: Hypo-osmolality, Carnitine deficiency, Hypomagnesemia, excessive inter-dialytic weight gain Rx: Dietary counseling, Sodium modeling, Saline or 50% dextrose bolus, ? Prophylactic Quinine sulfate or Oxazepam Rx: Dietary counseling, Sodium modeling, Saline or 50% dextrose bolus, ? Prophylactic Quinine sulfate or Oxazepam Slide 60 Neuromuscular complications Seizures Seizures Restless legs syndrome Restless legs syndrome Headache Headache Slide 61 Dialysis Disequilibrium Syndrome (DDS) Risk factors: Young age, severe and chronic azotemia, Initial dialysis treatment, High flux/ large surface area dialyzer Risk factors: Young age, severe and chronic azotemia, Initial dialysis treatment, High flux/ large surface area dialyzer Symptoms: Headache, nausea, emesis, blurred vision, hypertension, disorientation, muscle twitching Symptoms: Headache, nausea, emesis, blurred vision, hypertension, disorientation, muscle twitching Slide 62 DDS Pathogenesis: Pathogenesis: 1. Reverse urea effect ( rapid reduction of serum urea while CSF urea concentration remains high) 2. Paradoxical CSF acidosis 3. Intracerebral accumulation of idiogenic osmoles in uremia Slide 63 DDS Treatment Treatment 1. Early detection of uremia, early intervention with dialysis 2. First few treatments should aim to achieve modest reduction in serum urea concentration ( 30% or less) 3. Sodium modeling, use of Bicarbonate dialysis, slow QB 4. Prophylactic use of Mannitol is not recommended Slide 64 Intradialytic Hemolysis Uncommon Uncommon From contamination of dialysate with Chloramine or Copper (deionization failure) From contamination of dialysate with Chloramine or Copper (deionization failure) From Methemoglobinemia from nitrate contamination From Methemoglobinemia from nitrate contamination Slide 65 Intradialytic Hypoxemia Arterial p O 2 drops by 5 to 30 mm Hg during Hemodialysis due to central Hypoxemia. Arterial p O 2 drops by 5 to 30 mm Hg during Hemodialysis due to central Hypoxemia. This is a result of a drop in CO 2 that accompanies correction of acidosis on dialysis This is a result of a drop in CO 2 that accompanies correction of acidosis on dialysis V/Q mismatch can occur due to pulmonary sequestration of activated leukocytes V/Q mismatch can occur due to pulmonary sequestration of activated leukocytes Acetate can induce respiratory muscle fatigue Acetate can induce respiratory muscle fatigue Slide 66 Intradialytic Hypoxemia Treatment : Supplemental oxygen during Hemodialysis in susceptible patients Treatment : Supplemental oxygen during Hemodialysis in susceptible patients