CHT Certified Hemodialysis Technician 5 — Questions and Answers
Question 1: The Association for the Advancement of Medical Instrumentation (AAMI) standard for maximum allowable bacteria count in water used for hemodialysis is:
- 10 CFU/mL
- 100 CFU/mL (Correct answer)
- 200 CFU/mL
- 500 CFU/mL
Correct answer: 100 CFU/mL
AAMI standards require dialysis water to contain fewer than 100 CFU/mL of bacteria to ensure patient safety during treatment.
Question 2: When disconnecting a patient at the end of hemodialysis, the blood is returned to the patient using:
- Heparinized normal saline pushed rapidly
- Normal saline rinse-back through the arterial line (Correct answer)
- Air pushed through the venous line to clear the tubing
- Hypertonic saline to maximize fluid return
Correct answer: Normal saline rinse-back through the arterial line
Blood is returned at treatment end by infusing normal saline through the arterial line, pushing blood from the circuit back to the patient through the venous line.
Question 3: A patient's dialysis adequacy lab results show a URR of 58%. According to KDOQI, this result indicates:
- Excellent dialysis adequacy exceeding target
- Adequate dialysis meeting minimum standards
- Inadequate dialysis requiring intervention (Correct answer)
- Normal variation not requiring adjustment
Correct answer: Inadequate dialysis requiring intervention
KDOQI recommends a minimum URR of 65%; a URR of 58% is below target and indicates inadequate urea reduction, requiring assessment of treatment parameters.
Question 4: Which action is the technician's FIRST priority when a patient reports sudden chest pain and difficulty breathing during dialysis?
- Slow the blood pump to 100 mL/min and observe
- Notify the charge nurse or physician immediately and assess for air embolism (Correct answer)
- Increase the dialysate flow rate to improve clearance
- Administer oxygen and continue treatment at reduced rate
Correct answer: Notify the charge nurse or physician immediately and assess for air embolism
Sudden chest pain with dyspnea during dialysis is a medical emergency potentially indicating air embolism, cardiac event, or hemolysis requiring immediate physician notification.
Question 5: Aluminum toxicity in dialysis patients historically occurred most commonly as a result of:
- Use of aluminum-containing antacids as phosphate binders
- Aluminum contamination in dialyzer membranes
- High aluminum content in dialysate from inadequately treated water (Correct answer)
- Intravenous iron preparations containing aluminum
Correct answer: High aluminum content in dialysate from inadequately treated water
Before modern water treatment standards, inadequately purified water delivered aluminum directly into the bloodstream via dialysate, causing dialysis dementia and bone disease.
Question 6: When a patient with a synthetic AV graft requires needle insertion, the technician should rotate needle sites to prevent:
- Hematoma formation at insertion points
- Aneurysmal dilation from repeated cannulation in the same area (Correct answer)
- Infection spreading along the graft material
- Thrombosis at the arterial anastomosis
Correct answer: Aneurysmal dilation from repeated cannulation in the same area
Repeated needle insertion at the same site in a graft causes localized weakness and aneurysm formation, so rotating sites (rope-ladder or buttonhole techniques) is essential.
Question 7: The purpose of the blood leak detector in the dialysis machine is to identify:
- Air bubbles entering the venous blood line
- Blood crossing from the blood compartment into the dialysate (Correct answer)
- Clot formation within the dialyzer fibers
- Pressure drops indicating access recirculation
Correct answer: Blood crossing from the blood compartment into the dialysate
The blood leak detector monitors dialysate effluent using optical sensors to detect hemoglobin, indicating a ruptured dialyzer membrane allowing blood to enter the dialysate compartment.
CHT Certified Hemodialysis Technician 5
The Association for the Advancement of Medical Instrumentation (AAMI) standard for maximum allowable bacteria count in water used for hemodialysis is: