water for dialysis part 1: components - mtfd · why water must be treated person on hemodialysis...

Water for Dialysis

Part 1: Components

Danilo B. Concepcion, CBNT, CHT-A, FNKF

[email protected]

(714)771-8944

The findings and conclusions in this presentation are those of the

author and do not necessarily represent the views of St. Joseph

Hospital

•Safety of Water and Dialysis Delivery: The highly-technical nature of dialysis treatments place the patients at significant risk if there is isolated or systemic failure to follow precise procedures.

Anemia Bone Disease Fever, Chills Hemolysis Hypotension Hypertension Muscle Weakness Metabolic Acidosis Methemoglobinemia with cyanosis Nausea & Vomiting Neurological Deterioration

5

Why Water Must be Treated

Person on Hemodialysis

• Blood is exposed to 360+ liters of water/ week

• Dialyzer membrane is thin, non-selective

• Nonfunctioning kidney

• Can experience harm or death from untreated water

Average Person

• Drinks 14 liters of water/week

• GI tract more selective

• Functioning kidney

10 - 14 Liters

350 - 450 Liters

6

The Role of Water in Hemodialysis

• Preparation of dialysate

• Reprocessing of hemodialyzers

7

How Water is Treated

The municipal or public water supply is made safe for dialysis by use of a water treatment system.

8

Sources of Water

• Ground Water

• Surface Water

• Municipal Water

9

Types of Contaminants

• Microorganisms

• Organic Contaminants

• Inorganic Contaminants

10

Water Treatment Standards

AAMI: Association for the Advancement of Medical

Instrumentation

CMS: Centers for Medicare & Medicaid Services

(Formerly HCFA)

FDA: Federal Drug Administration

State: Each state sets it’s own standards

Facility: Policies and Procedures

11

CHEMICAL mg/L

Nitrate 2.00

Zinc 0.10

Copper 0.10

Aluminum 0.01

AAMI STANDARDS

CHEMICAL mg/L

Fluoride 0.20

Chloramine 0.10

Free Chlorine 0.50

Sulfate 100.00

12

CHEMICAL mg/L

Barium 0.100

Selenium 0.090

Chromium 0.014

Lead 0.005

Silver 0.005

Thallium 0.002

CHEMICAL mg/L

Cadmium 0.0010

Mercury 0.0002

Arsenic 0.0050

Beryllium 0.0004

Antimony 0.0060

AAMI STANDARDS (cont.)

13

AAMI STANDARDS (cont.)

CHEMICAL mg/L

• Calcium 2.0

• Magnesium 4.0

• Sodium 70.0

• Potassium 8.0

14

The Water Treatment System Components

• Backflow Preventer

• Temperature Blending Valve

• Booster Pump

• Sediment, Depth, or Multimedia Filter

• Water Softener

• Carbon Tanks

• Micron Filters

• Reverse Osmosis (R.O.)

• Deionization Tanks (D.I.)

• Storage Tank

• Ultrafilters

• Flowpath, Pipes, and Gauges

15


Backflow Preventer

• Prevents water and/or disinfectants from flowing backward from the dialysis unit into the municipal (public) water supply

Backflow Preventer

• Prevents reverse flow of water and or contaminants through the valve, which would contaminate the potable drinking water supply.

• Installed, tested by licensed plumber

18


Temperature Blending

Valve

• Mixes incoming cold water with water from the hot water heater

19


Booster Pump

• Boosts water

pressure from 40

psi to 60-80 psi

(pounds per

square inch)

Sediment Filter

21


Sediment, Depth, or Multimedia Filter

• Designed to catch large suspended particles such as algae, rust, and sand

Sediment Filter

• What is it and What does it do? – Tank containing several layers of different

media designed to filter sediment particles from city water supply

• How do we Monitor it? – Sediment filter is monitored on daily basis for:

• Pressure drop across filters • Backwash timer heads set to correct time

of day –Re-generated or “backwashed” during

hours of non-operation in order to clean the media

Sediment Filter

• What do we do if it fails?

– Depending on facility’s “Silt Density Index”, RO may handle short term bypass of this device

• What is the adverse impact on the patient if it fails?

– Failure of this equipment may not effect operation at all, depending on city feed water quality

24


Water Softener

• Removes calcium and magnesium

Na+

Na+

Na+ Na+

Na+

Na+

Na+

Na+

Na+

Softener

Resin Bead Ca++

Cl- Cl-

Cl- Cl-

Ca++ Ca+ Ca++ Ca++ Ca++

2Na+

2Na+

2Na+

2Na+ 2Na+

2Na+

Softeners & Exchange Tanks

For the

removal of

water

hardness

(calcium,

magnesium)

in exchange

for sodium

NaCl

solution

Softeners and Exchange Tanks

Monitoring

– Record pressure pre and post softener

• At least daily

– Check hardness post softener

• In a.m. and p.m.

• <2 grains hardness (<35 mg/L)

Softeners

• Shall be fitted with a mechanism to prevent water containing the high concentrations of sodium chloride used during regeneration from entering the product water line during regeneration – shall be interlocked.

• Shall be measured at the end of each treatment day.

Water Softener


– Softeners may be temporarily bypassed

– Running RO without a softener for prolonged amount of time could cause permanent damage to RO membranes


– Prolonged failure of water softener can cause failure of RO membranes, and can also cause further patient complications

30


Carbon Tanks

• Used to remove chlorine and chloramine

• Two Carbon tanks are used in sequence, a “Worker” and a “Polisher”

SA = 1000 m2/gm or 3280 f2/0.002 pounds

Carbon Tanks

Iodine number of 900 or higher

Acid washing removes manufacturing debris

Tanks are sized for Empty Bed Contact Time (EBCT).

10 minutes EBCT for chloramine removal

V=(Q x EBCT)/7.48 – 1.2 gal/min EBCT 10 min./7.48 = 1.6ft3

Two tanks in series for total EBCT, worker and

polisher

Carbon Tanks

Monitoring

– Check total chlorine post first tank

• Before every shift

• Every four hours

– Pre and post pressure

Carbon Tanks


– If breakthrough is noted on primary tank, total chloramine level should immediately be checked after secondary tank

– If there is no breakthrough noted after secondary tank, treatments can continue with increased frequency (at least hourly) of total chloramine monitoring with Medical Director approval for up to 72 hrs

– If breakthrough is noted after secondary GAC tank, treatment must be stopped immediately

– Both tanks must be re-bedded within 72 hrs

Carbon Tanks


– Failure of GAC tanks may result in elevated level of chlorine and chloramine in pre-treated water

– Chlorine and chloramine will cause permanent damage to most RO membranes

– Chlorine and chloramine in product water can lead to hemolysis or death

36


Micron Filters

• Micron filters remove small particulate matter

Prefilters

Final Barrier against particles or debris that can damage RO pumps and membranes

Head

Flow

Outlet

O-ring

Filter Cartridge

Shell

Flow

Prefilters

Considerations/Concerns Disposable cartridge with a 3 to 5 micron

filter size

Change prefilter when • 8-10 PSI higher than clean pressure loss

• Or on a routine schedule

Disinfect bowl and head to remove biofilm

AAMI standards require housing to be opaque

Membrane Element

Permeate Flow

Concentrate

Permeate

Feed Solution

Collection Tube

Monitors and Controls

Indicators of water quality (conductivity, TDS, resistivity)

Local

Remote

% Rejection (Input - Product / Input) x 100

(V200) Include a means to prevent patient exposure to

unsafe product water, such as diversion of the product

water to drain…

Disinfection lock-out

V199 – V201 R.O. • 5.2.7 a means to prevent patient exposure to

unsafe product water, such as diversion of the product water to drain… – V200 IG: In the absence of an automatic divert to

drain valve for the RO, facility staff must demonstrate knowledge of the requirement to manually stop water flow to the dialysis machines…

• 6.2.7 chemical analysis – Installation, membrane replacement, seasonal

variations, <90% rejection

Post Treatment Components

• U.V. Light

• Sub-micron/Ultra-filters

Ultraviolet Irradiator

UV Lamp

Quartz Sleeve

‘O’ Ring

Quartz Nipple

Plug

Washer

Lamp Harness Assembly

Pilot Light

Power Supply

Kills or alters DNA of bacteria as water passes through UV


• UV is a mercury vapor lamp enclosed in a fused quartz sleeve

• Endotoxins may be produced as it kills bacteria

• Ultrafilter recommended after UV for endotoxin control

UF may be placed at points of use

Check LAL


• UV Maintenance

Routine cleaning REQUIRED to

retain efficiency

• Lamp replacement

Once per year, not when burns out

Submicron and Ultra Filters

• Sub micron filter

0.1 through 1.0 microns

• UF filters/Membranes rated by

pore size

Generally .001 through 0.05 microns

Ultrafiltration (UF)

• Prevents patient from being “final filter”

• Removes Bacteria and endotoxin – Validated medical filter (absolute rating)

– Rated in nominal MWCO

• Problem with decrease in pressure and flow which affects velocity

• Place at points of use: – Dialyzer reprocessing equipment

– Bicarbonate filling station

– Dialysis machine on dialysate

water for dialysis part 1: components - mtfd · why water must be treated person on hemodialysis...

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