CDN Water Treatment and Dialysis Equipment 1 — Questions and Answers
Question 1: What is the primary purpose of reverse osmosis (RO) in the dialysis water treatment system?
- Remove chlorine and chloramines
- Remove bacteria and endotoxins
- Remove dissolved ionic contaminants including heavy metals (Correct answer)
- Soften hard water by removing calcium
Correct answer: Remove dissolved ionic contaminants including heavy metals
Reverse osmosis removes dissolved ionic contaminants such as aluminum, fluoride, and heavy metals by forcing water through a semi-permeable membrane under pressure.
Question 2: Which chemical contaminant in municipal water poses the greatest risk of hemolytic anemia in dialysis patients if not removed?
- Calcium
- Fluoride
- Chloramine (Correct answer)
- Nitrate
Correct answer: Chloramine
Chloramine, used in municipal water disinfection, causes oxidative hemolytic anemia if not adequately removed before dialysis water reaches the patient.
Question 3: What is the AAMI recommended maximum level for bacteria in dialysis water?
- 10 CFU/mL
- 100 CFU/mL (Correct answer)
- 200 CFU/mL
- 500 CFU/mL
Correct answer: 100 CFU/mL
AAMI standards specify that dialysis water should contain no more than 100 colony-forming units per milliliter (CFU/mL) of bacteria.
Question 4: What happens to the water softener resin during the regeneration process?
- Resin is replaced with new material
- Sodium ions replace accumulated calcium and magnesium ions via a salt brine flush (Correct answer)
- Resin is sterilized with bleach
- Carbon particles are backwashed out of the system
Correct answer: Sodium ions replace accumulated calcium and magnesium ions via a salt brine flush
During regeneration, a concentrated sodium chloride (brine) solution flushes through the resin, replacing accumulated calcium and magnesium with sodium ions, restoring softening capacity.
Question 5: How often should the total chlorine level in dialysis water be tested at minimum?
- Weekly
- Daily before each patient treatment (Correct answer)
- Monthly
- Quarterly
Correct answer: Daily before each patient treatment
Total chlorine must be tested daily before each patient treatment shift, as breakthrough can occur rapidly and cause patient harm if not detected promptly.
Question 6: What is the maximum allowable endotoxin level in standard hemodialysis water per AAMI standards?
- 0.03 EU/mL
- 0.25 EU/mL (Correct answer)
- 2 EU/mL
- 5 EU/mL
Correct answer: 0.25 EU/mL
AAMI standards allow a maximum endotoxin level of 0.25 EU/mL in standard hemodialysis water, with stricter limits of 0.03 EU/mL for ultra-pure water.
CDN Water Treatment and Dialysis Equipment 1
What is the primary purpose of reverse osmosis (RO) in the dialysis water treatment system?