Water for Dialysis Part 1: Components

Transcription

1 Water for Dialysis Part 1: Components Danilo B. Concepcion, CBNT, CHT-A, FNKF (714) The findings and conclusions in this presentation are those of the author and do not necessarily represent the views of St. Joseph Hospital

2 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.

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4 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 Average Person Drinks 14 liters of water/week GI tract more selective Functioning kidney Liters Person on Hemodialysis Blood is exposed to liters of water/ week Dialyzer membrane is thin, non-selective Nonfunctioning kidney Can experience harm or death from untreated water Liters 5

6 The Role of Water in Hemodialysis Preparation of dialysate Reprocessing of hemodialyzers 6

7 How Water is Treated The municipal or public water supply is made safe for dialysis by use of a water treatment system. 7

8 Sources of Water Ground Water Surface Water Municipal Water 8

9 Types of Contaminants Microorganisms Organic Contaminants Inorganic Contaminants 9

10 Water Treatment Standards AAMI: Association for the Advancement of Medical Instrumentation CMS: FDA: State: Facility: Centers for Medicare & Medicaid Services (Formerly HCFA) Federal Drug Administration Each state sets it s own standards Policies and Procedures 10

11 AAMI STANDARDS CHEMICAL mg/l Fluoride 0.20 Chloramine 0.10 Free Chlorine 0.50 Sulfate CHEMICAL mg/l Nitrate 2.00 Zinc 0.10 Copper 0.10 Aluminum

12 AAMI STANDARDS (cont.) CHEMICAL mg/l Barium Selenium Chromium Lead Silver Thallium CHEMICAL mg/l Cadmium Mercury Arsenic Beryllium Antimony

13 AAMI STANDARDS (cont.) CHEMICAL mg/l Calcium 2.0 Magnesium 4.0 Sodium 70.0 Potassium

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 14

15 The Water Treatment System Components Backflow Preventer Prevents water and/or disinfectants from flowing backward from the dialysis unit into the municipal (public) water supply 15

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17 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 The Water Treatment System Components Temperature Blending Valve Mixes incoming cold water with water from the hot water heater 18

19 The Water Treatment System Components Booster Pump Boosts water pressure from 40 psi to psi (pounds per square inch) 19

20 Sediment Filter

21 The Water Treatment System Sediment, Depth, or Multimedia Filter Designed to catch large suspended particles such as algae, rust, and sand Components 21

22 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

23 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 The Water Treatment System Components Water Softener Removes calcium and magnesium 24

25 Softener Resin Bead Na+ Na+ Na+ Na+ Na+ Na+ Na+ Ca++ Ca++ Na+ Ca++ Ca++ Ca+ Ca++ 2Na+ 2Na+ 2Na+ Na+ Cl- 2Na+ 2Na+ 2Na+ Cl- Cl- Cl-

26 Softeners & Exchange Tanks For the removal of water hardness (calcium, magnesium) in exchange for sodium NaCl solution

27 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)

28 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.

29 Water Softener What do we do if it fails? Softeners may be temporarily bypassed Running RO without a softener for prolonged amount of time could cause permanent damage to RO membranes What is the adverse impact on the patient if it fails? Prolonged failure of water softener can cause failure of RO membranes, and can also cause further patient complications

30 The Water Treatment System Components Carbon Tanks Used to remove chlorine and chloramine Two Carbon tanks are used in sequence, a Worker and a Polisher 30

31 SA = 1000 m 2 /gm or 3280 f 2 /0.002 pounds

32 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)/ gal/min EBCT 10 min./7.48 = 1.6ft 3 Two tanks in series for total EBCT, worker and polisher

33 Carbon Tanks Monitoring Check total chlorine post first tank Before every shift Every four hours Pre and post pressure

34 Carbon Tanks What do we do if it fails? 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

35 Carbon Tanks What is the adverse impact on the patient if it fails? 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 The Water Treatment System Components Micron Filters Micron filters remove small particulate matter 36

37 Prefilters Head Outlet Flow O-ring Filter Cartridge Flow Final Barrier against particles or debris that can damage RO pumps and membranes Shell

38 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

39 Membrane Element Permeate Flow Concentrate Permeate Feed Solution Collection Tube

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42 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

43 V199 V201 R.O 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 chemical analysis Installation, membrane replacement, seasonal variations, <90% rejection

44 Post Treatment Components U.V. Light Sub-micron/Ultra-filters

45 Ultraviolet Irradiator Kills or alters DNA of bacteria as water passes through UV Quartz Sleeve UV Lamp O Ring Quartz Nipple Pilot Light Power Supply Lamp Harness Assembly Washer Plug

46 Ultraviolet Irradiator 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

47 Ultraviolet Irradiator UV Maintenance Routine cleaning REQUIRED to retain efficiency Lamp replacement Once per year, not when burns out

48 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

49 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