CBET Healthcare Technology Problem-Solving 4

Question 1

A ventilator's tidal volume display reads 500 mL but a calibrated test lung measurement shows only 420 mL. What is the most likely cause?

Accepted Answer

Flow sensor calibration drift

Answer

Flow sensor drift is the most common cause of tidal volume display inaccuracy when the set and delivered volumes differ consistently.

Question 2

A nurse reports that a patient's SpO2 monitor reads 98% while the patient appears cyanotic. Which troubleshooting step should be performed first?

Accepted Answer

Check probe placement and peripheral perfusion

Answer

Poor perfusion or improper probe placement are the most common causes of falsely high SpO2 readings before escalating to hardware replacement.

Question 3

An infusion pump alarms 'upstream occlusion' but the tubing appears clear. What should the BMET check next?

Accepted Answer

Closed roller clamp or kinked tubing upstream of the pump

Answer

A closed clamp or subtle kink upstream of the pump head is the most frequent cause of upstream occlusion alarms when visible tubing appears unobstructed.

Question 4

During a preventive maintenance inspection, an electrosurgical unit's leakage current measures 450 µA chassis to ground. What action is required?

Accepted Answer

Remove from service; leakage exceeds the 300 µA limit for ESUs

Answer

NFPA 99 and AAMI ES60601-1 limit chassis leakage current to 300 µA for patient-care equipment; 450 µA requires the unit be taken out of service.

Question 5

A defibrillator delivers only 150 J when set to 200 J during an output verification test. After replacing the energy storage capacitor the problem persists. What should be investigated next?

Accepted Answer

Charging circuit and charge relay

Answer

If the capacitor is confirmed good, the charging circuit or charge relay is the next most likely cause of low delivered energy.

CBET - Certified Biomedical Equipment Technician Practice Test

CBET - Certified Biomedical Equipment Technician Practice Test

CBET Healthcare Technology Problem-Solving 4