CHBT Dialysis Equipment Maintenance and Troubleshooting 2 — Questions and Answers
Question 1: What is the function of the transducer protector on a hemodialysis machine?
- Prevents blood contamination of the pressure monitoring port (Correct answer)
- Measures arterial blood pressure
- Filters dialysate before it enters the dialyzer
- Controls the ultrafiltration rate
Correct answer: Prevents blood contamination of the pressure monitoring port
The transducer protector is a hydrophobic filter that prevents blood or fluid from entering the machine's pressure transducer, protecting against cross-contamination.
Question 2: A dialysis machine displays a low arterial pressure alarm. Which condition is LEAST likely to cause this?
- Collapsed access site
- Blood pump running too fast for access flow
- Kinked arterial blood line
- High dialysate conductivity (Correct answer)
Correct answer: High dialysate conductivity
Low arterial pressure alarms are caused by flow restrictions or inadequate access blood supply; dialysate conductivity does not directly affect arterial line pressure.
Question 3: How is the heparin pump on a hemodialysis machine typically primed before treatment?
- Flushed with saline until heparin appears at the needle tip (Correct answer)
- Filled with dialysate
- Run at maximum rate for 2 minutes
- Pre-filled by the manufacturer
Correct answer: Flushed with saline until heparin appears at the needle tip
The heparin infusion line is primed with saline and then heparin is advanced to the needle tip to remove air and ensure accurate dosing from the start.
Question 4: Which parameter does the air detector/foam detector on a dialysis machine monitor?
- Venous blood line for air or foam before blood returns to the patient (Correct answer)
- Dialysate for air bubbles
- Blood pump occlusion
- Dialyzer membrane integrity
Correct answer: Venous blood line for air or foam before blood returns to the patient
The air/foam detector is positioned on the venous return line and will trigger a clamp and alarm to prevent air embolism in the patient.
Question 5: What is the recommended storage condition for unused dialyzer cartridges?
- Room temperature, away from direct sunlight, within manufacturer expiration date (Correct answer)
- Refrigerated at 2–8°C
- Submerged in sterile saline
- Frozen until use
Correct answer: Room temperature, away from direct sunlight, within manufacturer expiration date
Dialyzers should be stored at controlled room temperature, protected from light and moisture, and used before the manufacturer's expiration date.
Question 6: If a dialysis machine's temperature sensor fails during treatment, what is the primary patient risk?
- Hemolysis from overheated dialysate (Correct answer)
- Hypoglycemia
- Air embolism
- Metabolic alkalosis
Correct answer: Hemolysis from overheated dialysate
Dialysate delivered above approximately 42°C can cause thermal hemolysis, destroying red blood cells and releasing potassium with potentially fatal consequences.
CHBT Dialysis Equipment Maintenance and Troubleshooting 2
What is the function of the transducer protector on a hemodialysis machine?