CHT Hemodialysis Technologist 4 — Questions and Answers
Question 1: When reprocessing a dialyzer with peracetic acid, what is the minimum required dwell time to achieve adequate disinfection?
- 5 minutes
- 11 hours (Correct answer)
- 6 hours
- 30 minutes
Correct answer: 11 hours
Peracetic acid dialyzer reprocessing requires a minimum 11-hour contact time to ensure effective high-level disinfection per AAMI standards.
Question 2: A patient reports itching, hives, and bronchospasm within minutes of starting dialysis with a new dialyzer. This presentation is MOST consistent with:
- Disequilibrium syndrome
- Type A (anaphylactic) first-use reaction (Correct answer)
- Type B first-use reaction
- Hemolysis
Correct answer: Type A (anaphylactic) first-use reaction
Type A first-use reactions are IgE-mediated anaphylactic responses that occur within minutes and include urticaria, bronchospasm, and cardiovascular collapse.
Question 3: What is the purpose of the 'negative pressure' test performed on a dialysis machine?
- Verify ultrafiltration rate accuracy (Correct answer)
- Check for blood leak detector sensitivity
- Test the integrity of the blood pump segment
- Confirm dialysate concentrate is connected properly
Correct answer: Verify ultrafiltration rate accuracy
The negative pressure test (or ultrafiltration test) verifies the machine's ability to accurately achieve the prescribed ultrafiltration rate.
Question 4: Which of the following is the MOST appropriate needle gauge for cannulating a well-developed AV fistula?
- 18-gauge
- 16-gauge (Correct answer)
- 14-gauge
- 21-gauge
Correct answer: 16-gauge
16-gauge needles are standard for AV fistula cannulation, balancing adequate blood flow (≥200 mL/min) with minimizing vessel trauma.
Question 5: Which AAMI water quality standard specifies the maximum allowable level of endotoxins in water used for hemodialysis?
- 0.25 EU/mL for standard, 0.03 EU/mL for ultrapure (Correct answer)
- 1.0 EU/mL for standard, 0.5 EU/mL for ultrapure
- 2.0 EU/mL for all dialysis water
- No endotoxin limits are specified
Correct answer: 0.25 EU/mL for standard, 0.03 EU/mL for ultrapure
AAMI/ANSI standards specify ≤0.25 EU/mL for standard dialysis water and ≤0.03 EU/mL for ultrapure water used in online hemodiafiltration.
Question 6: A patient develops pink-tinged blood in the dialysate effluent during treatment. This MOST LIKELY indicates:
- Dialyzer clotting
- Blood leak through a ruptured membrane (Correct answer)
- Hemolysis from kinking of blood lines
- Incorrect dialysate pH
Correct answer: Blood leak through a ruptured membrane
Pink or red dialysate effluent indicates a blood leak through the dialyzer membrane and requires immediate treatment termination.
Question 7: What is the primary reason for using bicarbonate-based rather than acetate-based dialysate in modern hemodialysis?
- Lower cost of bicarbonate concentrate
- Better hemodynamic tolerance and fewer side effects with bicarbonate (Correct answer)
- Acetate provides superior phosphate removal
- Bicarbonate increases calcium levels more effectively
Correct answer: Better hemodynamic tolerance and fewer side effects with bicarbonate
Bicarbonate dialysate provides more physiologic buffering with fewer cardiovascular side effects (hypotension, nausea) compared to acetate.
CHT Hemodialysis Technologist 4
When reprocessing a dialyzer with peracetic acid, what is the minimum required dwell time to achieve adequate disinfection?