Water Treatment Unit

For Hemodialysis machines

Hemodialysis Solution

Dialysis solution is prepared fromDialysis solution is prepared from

Purified waterPurified water

ConcentrateConcentrate

+

Water – significance for the patient

g Needed by a human being app. 500- 800 litres per every treatment

g Dialysis patients need app. 20 m3 /yrg Demands of water for dialysis is very high

Types of pollutiong Organic pollutants

particles, colloids, bacteria, pyrogens, chloramines, pesticides

g Inorganic pollutants

monovalent/ polyvalent ions, especially calcium, sodium, magnesium, nitrate, copper, aluminium etc.

Colloids+

+

+++

+

+

+ +

+

+++

+

+

+- -

-

-

- --- - -

-

-

- ---

Water contamination is harmful for dialysis patient:Water contamination is harmful for dialysis patient:

Complications : is added for/by :

Anemia, dementia, bone

disease

Flocculating suspended

particlesAluminum:

Hemolytic anemia

Preventing bacterial

proliferationChloramine:

Pruritis, Nausea, Atrial

fibrillation

Reduce tooth decay Fluoride :

Hemolytic anemia, toxicity

Metal pipesCopper, Zinc

Lead

Pyrogenic reactions

Contaminated water

Bacteria and Endotoxins

Methods of purifying water:Methods of purifying water:

Pretreatment Primary purification Distribution

Pretreatment Primary purification Distribution

gInstallation of water pre-treatment and RO system

Mec

hanic

al Filte

r

Sand

filter

Softe

ner

Wat

er m

eter

Carbo

n filt

er Rever

se o

smos

is

with m

echa

nical

Filter

Salt ta

nk

Methods of purifying water:Methods of purifying water:

Pretreatment Primary purification Distribution

Pretreatment Primary purification Distribution

pretreatment:pretreatment:

Water softener Carbon adsorption

Water softener Carbon adsorption

Softener:Softener:

SOFTENER

Carbon adsorption:Carbon adsorption:

Adsorption by activated Carbone Is utilized to remove

Chlorine and Chloramines

Adsorption by activated Carbone Is utilized to remove

Chlorine and Chloramines

2-Activated carbon filter for adsorption principle:

*van der Waals forces *high specific surface (100g act. carbon – ca. 100.00 m2)

◊ remove chlorine from drinking water

Methods of purifying water:Methods of purifying water:

Pretreatment Primary purification Distribution

Pretreatment Primary purification Distribution

Methods of purifying water:Methods of purifying water:

Pretreatment Primary purification Distribution

Pretreatment Primary purification Distribution

Primary purification:Primary purification:

Reverse osmosis Deionization

Reverse osmosis Deionization

Reverse osmosis:Reverse osmosis:

It removes more than 95% of ionic

contamination and nonionic contaminations

It removes more than 95% of ionic

contamination and nonionic contaminations

clear water

Osmotic pressure

saline solution

semipermeable membrane

Principle of Osmosis

pressure

saline solutionclear water

semipermeable membrane

Principle of Reverse Osmosis

Reverse osmosis apparatus

Direct and indirect water feed distribution system

Deionization:Deionization:

Methods of purifying water:Methods of purifying water:

Pretreatment Primary purification Distribution

Pretreatment Primary purification Distribution

Methods of purifying water:Methods of purifying water:

Pretreatment Primary purification Distribution

Pretreatment Primary purification Distribution

 The main function of the dialysate, is to remove waste material from the blood and to keep useful material from leaving the blood. Electrolytes and water are some materials included in the dialysate so that their level in the blood can be controlled

Dialysis solutions preparation:Dialysis solutions preparation:

Fixed volumes of dialysate concentrate mixed with

fix volumes of heated purified water

The final dialysate solution is checked by conductivity

Fixed volumes of dialysate concentrate mixed with

fix volumes of heated purified water

The final dialysate solution is checked by conductivity

Biff F. Palmer

Bicarbonate powder obviates the problem of bicarbonate growth in bicarbonate solutions

Hemodialysis solution

Concentrations of dialysate components used in hemodialysis :

Sodium (meq/L) 135 to 155 Potassium (meq/L) 0 to 4 Calcium (mmol/L) 1.25 to 1.75 (2.5 to 3.5 meq/L) Magnesium (mmol/L) 0 to 0.75 (0 to 1.5 meq/L) Chloride (meq/L) 87 to 120 Bicarbonate (meq/L) 25 to 40 Glucose (g/dL) 0 to 0.20

In early 1960s acetate was standard buffer

Acetate lead to cardiovascular instability and hypotension during dialysis.

Acetate buffer

Acetate buffer

Hemodynamic instability Pts with reduced mass muscle more

intolerant to acetate buffer included malnourished Pts,elderly Pts and women.

Bicarbonate (meq/L) 25 to 40

Standard solutions have 35 or 38 meq/L In alkalemic pts (metabolic or respiratory)

standard solutions must be changed to a solution with 20-28 meq/L of bicarbonate

Concentration of base adjusted to a predialysis plasma con of 20-23 meq/L

Con beyond 20-23 meq/L increased risk of Ca-P precipatation and cardiac arrhythmia

Bicarbonate Concentrate

NaHCO3

Bicarbonate Concentrate

NaHCO3

Acid Concentrate

(acetic acid, citric acid ,Na, K, Mg, Cl, dextrose

Acid Concentrate

(acetic acid, citric acid ,Na, K, Mg, Cl, dextrose

HCO3 + H+ = H2CO3

PH: 7-7.4

HCO3 + H+ = H2CO3

PH: 7-7.4

NaHco3 = 32mmol ± 8 mmol

Bicarbonate Concentration for Acidotic Patient =35-38 mEq/L

Sodium level:135-145meq/L

Dialysate with low Na level predispose to hypotension and cramps because of hypoosmolality and more fluid shifting from extracellular space to intracellular space.

Dialysate with high Na level may cause thirst and weight gain and prevent hypotension during dialysis.

Standard Dilution 1 + 34Variable 1 + 25 1 + 37 Acetate 135mmol Base Na Bicarbonate 138mmol

NaHco3 + Acid Solution 32mmol + 106 mmol

Potassium level :0-4meq/L

Usual dialysis K level is 2 meq/L unless predialysis plasma K is less than 4.5 or unless patient is receiving digitalis.

In the two instances ,dialysis K level is 3 meq/L

Calcium level:2.5-3.5 meq/L

In pts taking calcium-containing phosphorus Ca level is 2.5 meq/L

In pts taking newer phosphate binder which don’t contain Ca , Ca level may increased towards 3.5meq/L

Air Detector

Blood Leak Detector

PT

PT = Pressure Transducer

PT

Venous clamp

Anticoagulant

Blood from Patient

Blood return to Patient

Dialysate In

Dialysate / UF Out (green / yellow)

Informational Display

A “Standard” HD Delivery System

PT

Mixing System

Conductivity Meter

Water, Acid Concentrate, Bicarbonate

Concentrate In

Pre-mixed or sorbent

regenerated dialysate

Saline

Drip Chamber

مایع نهایی غلظتبیکربنات دیالیز

Na :135meq/lK:1 & 2 meq/lMg:1 meq/lCa:2.5 meq/lCl:104 meq/lAcetate :35 meq/lGlucose : 200mg/dl

Na :106 + 32 meq/lK:1 & 2 meq/lMg:1 meq/lCa:2.5 meq/lCl:111.5 meq/lAcetate :3.5 meq/lGlucose : 200mg/dlBicarbonate :32 meq

مایع نهایی غلظتاستات دیالیز

What is sodium modeling in hemodialysis patients?

What is sodium modeling in hemodialysis patients?

Fluid removal

Plasma refilling

Low Na 130-135 meq/l

Na

Fluid removal Fluid removal

Na

Increased risk of hypotension

Historically the dialysate Na was maintained at hyponatremic level, 130-135:

Historically the dialysate Na wasmaintained at hyponatremic level, 130-135:

To prevent: Intradialytic hypertension Thirsty Interdialytic weight gain

To prevent: Intradialytic hypertension Thirsty Interdialytic weight gain

Disadvantages of dialysates with low sodium concentration:

Disadvantages of dialysates with lowsodium concentration:

Increased risk of hypotension Increased risk of intradialytic cramps Increased risk of dialysis disequilibrium

syndrome

Increased risk of hypotension Increased risk of intradialytic cramps Increased risk of dialysis disequilibrium

syndrome

Water movement during standard hemodialysis

Water movement

Intracellular fluid Extracellular fluid Dialyzer

Osmolality320 mosm/kg

Osmolality320 mosm/kg

Loss of urea and water

step1

step2

step3

280

Osmolality320 mosm/kg

Falling to 290mosm/kg

as diffusion occurs

Compensatory refilling

urea removed by dialyzer

Effluent Dialysate

Inffluent Dialysate

urea sequestration in tissue

Increased intracellular osmolarity

fluid

Na

fluid

Causes of Intradialytic hypotension(IDH(

Intradialytic Hypotension

Reduced ECVImpaired Vaso-

constriction

Heart problems

Myocardial Infarction

Structural heart dis.

Arrythmias

Pericardial tamponadeDialyzer Rxn Air embolism

Hemolysis

Hemorrhage

Reduced plasma refill-

ing rate

Excessive fluid removal

Ultrafiltration rate > 0.35 ml/min/kg

Decrease in plasma vol. > 20%

Patient-related factors

Autonomic neuropathy (e.g. DM, Uremia)Antihypertensive medications

Sympathetic failure ( 적절한 plasma NE↑ 가 無 )RAS and arginine-vasopressin syst. sensitivity↓

Food ingestion(splanchnic vasodilation)Tissue ischemia(adenosine mediated)

Bacterial sepsisIntradialytic venous pooling

Core body temp↑.Anemia.

Dialysis-related factors

Acetate dalysate (adenosine-mediated)Low dialysate Na &/or ionized Ca conc.

Complemant activation (C3a and C5a-mediated)Cytokine generation(IL-1 and NO-mediated)

High dialysate sodium:High dialysate sodium:

Advantages:

Decreased risk of hypotension

Decreased risk of intradialytic cramps

Decreased risk of dialysis disequilibrium syndrome

Advantages:

Decreased risk of hypotension

Decreased risk of intradialytic cramps

Decreased risk of dialysis disequilibrium syndrome

Disadvantages:

Increased rate of hypertension

Interdialytic weight gain

Polydipsia

Disadvantages:

Increased rate of hypertension

Interdialytic weight gain

Polydipsia

Low Na >145 meq/l

Na

Fluid removal Plasma refilling

Na

Different patterns of sodium modeling Different patterns of sodium modeling

Na concentration

Hours after dialysis initiation

145-155 meq/lit

135-140 meq/lit

Dialysate Na should be regulated based on serum Na:

Dialysate Na should be regulated based onserum Na:

hyponatremia:

If Na > 130: Dialysate Na: 140-(140-predialysis Na(

If Na<130: Dialysate Na: Predialysis Na + 15-20

Hypernatremia:

Dialysate Na: Predialysis Na-2 mmol

hyponatremia:

If Na > 130: Dialysate Na: 140-(140-predialysis Na(

If Na<130: Dialysate Na: Predialysis Na + 15-20

Hypernatremia:

Dialysate Na: Predialysis Na-2 mmol