hemodialysis

1. Hemodialysis: History and
Current Perspective
Nadeem A Siddiqui MD
Dallas Nephrology Associates

2. Hemodialysis:History and Current
Perspective
 History of Dialysis
 Principles of Hemodialysis
 Practice of Hemodialysis
 Complications of Hemodialysis

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

5. Necessary pre-requisites for
Hemodialysis
1) Semi-permeable
membrane
2) Anticoagulation
3) Knowing what to
remove and how
much of it

6. 1773: Nurepuel isolates Urea by boiling
urine in a pan

7. 1828: Wohler
synthesizes Urea and
describes its
molecular structure

8. Thomas Graham (1805-1869)

9. 1850 Glasgow,
Scotland:
Thomas Graham ‘s
experiment to
demonstrate diffusion
across a semi-
permeable membrane
(Pergamon paper)

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
 Addition of Camphor to this substance led to the
synthesis of stable and strong “plastics”
 1957:Helmut Staldiger polymerized “Cellulose”

14. 1913:The First Hemodialysis
Experiment
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40
50
60
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80
90
1st
Qtr
2nd
Qtr
3rd
Qtr
4th
Qtr
East
West
North

15. 1937: William
Thalhimer successfully
lowers BUN by
performing
Hemodialysis in
anephric dogs

16. 1926:The First Human Experiment
 George Haas used a
collodion tube
arrangement to
successfully dialyze
human subjects
 Allergic reactions to
impurities in Hirudin
led him to abandon
his experiments

17. 1937:Nils Alwall used
the Alwall Kidney to
perform the first ever
hemodialysis
treatment at the
university of Lund,
Sweden

19. “ If I have seen farther it is because I have
stood on the shoulders of Giants”
Sir Isaac Newton

20. Hemodialysis:History and Current
Perspective
 History of Dialysis
 Principles of Hemodialysis

21. Mechanisms of Solute transfer
 Diffusion
 Convection

22. Diffusive Clearance
 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

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 can be made to move across a SPM
by the application of either a hydrostatic
or an osmotic gradient

26. Hemodialysis:History and Current
Perspective
 History of Dialysis
 Principles of Hemodialysis
 Practice of Hemodialysis

27. The Hemodialysis circuit

28. Dialysis Membranes
Membrane Hydr.Perm. Examples Biocomp.
Regen.
cellulose
Low flux cuprophane Poor
Modif.
Cellulose
Low/High
Flux
Cell.acetate
Cell di-acet.
Interm.
Synthetic High/Low
flux
PAN,PS,PA,
PC,PMMC
Good

29. Dialysis Solution
Component Concentration
mmol/L
Na 140
K 2
Ca 1.25 (5 mg/dl)
Mg 0.5 (1.2 mg/dl)
Acetate 3.0
Chloride 108
Bicarbonate 35
Glucose 5.6 (100 mg/dl)

30. Water Purification

33. Water Treatment System for
Hemodialysis

34. Vascular Access

43. Indications for initiating
Hemodialysis
 In patients with calculated creatinine clearance <20 ml/min/1.73 m2
the onset of:
*Uremic symptoms
Nausea/emesis
Altered sleep pattern
*Altered mental status
Coma
Stupor
Tremor
Asterixis
Clonus
Seizures

44. Indications for Hemodialysis
*Pericarditis or Tamponade (urgent
indication)
*Uremic platelet dysfunction (urgent
indication)
*Refractory volume overload
*Refractory hyperkalemia
*Refractory Metabolic acidosis with anuria

45. Indications for Hemodialysis
 Steadily worsening renal function in a
patient with measured 24 hour urinary
creatinine clearance<15 ml/min when
accompanied by worsening azotemia, poor
nutritional status and refractory edema

46. Equations for estimation of renal
function
 Cockcroft and Gault equation
 MDRD Formula

47. The Cockcroft-Gault equation
 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

48. The MDRD formula
Modification of diet in renal disease study JASN2000
 GFR (ml/min/1.73m2)=
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.

49. Measurement of nutritional status
 Physical Exam
Skin fold thickness
Mid arm muscle thickness
 Protein catabolic rate <1*
 Serum Albumin
 Serum Cholesterol
 Blood Lymphocyte count

50. Monitoring Dialysis Adequacy

54. Hemodialysis:History and CURRENT
Perspective
 History of Dialysis
 Principles of Hemodialysis
 Practice of Hemodialysis
 Complications of Hemodialysis

55. Complications of Hemodialysis
1. Dialysis Reactions
2. Intradialytic Hypotension
3. Neuromuscular complications
4. Dialysis dysequilibrium
5. Hemolysis
6. Intradialytic hypoxemia
7. Postdialysis syndrome
8. Cardiac arrhythmia and sudden death
9. Steal syndrome
10. Dialysis associated hypoxemia
11. Air embolism
12. Metabolic derangements

56. Dialysis Reactions

58. Management of Intradialytic
Hypotension
1. Assess dry weight frequently
2. Avoid BP meds before HD
3. Avoid rapid UF
4. Use sequential UF and HD
5. Avoid feeding patients on HD
6. Use Sodium modeling
7. Use HCO3 based dialysate
8. Keep Hct >33
9. Use non Cellulosic membranes
10. Keep Dialysate temperature<37 degrees Celsius
11. Assess cardiac function, r/o pericardial effusion/tamponade

59. Neuromuscular Complications:
Muscle Cramps
 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

60. Neuromuscular complications
 Seizures
 Restless legs syndrome
 Headache

61. Dialysis Disequilibrium Syndrome
(DDS)
 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

62. DDS
 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

63. DDS
 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

64. Intradialytic Hemolysis
 Uncommon
 From contamination of dialysate with
Chloramine or Copper (deionization
failure)
 From Methemoglobinemia from nitrate
contamination

65. Intradialytic Hypoxemia
 Arterial p O2 drops by 5 to 30 mm Hg during
Hemodialysis due to central Hypoxemia.
 This is a result of a drop in CO2 that
accompanies correction of acidosis on dialysis
 V/Q mismatch can occur due to pulmonary
sequestration of activated leukocytes
 Acetate can induce respiratory muscle fatigue

66. Intradialytic Hypoxemia
 Treatment : Supplemental oxygen during
Hemodialysis in susceptible patients