CABT Medical Equipment Operations 2 — Questions and Answers
Question 1: Which parameter is most critical to verify before connecting a patient to a mechanical ventilator?
- Battery backup level
- Tidal volume setting (Correct answer)
- Display brightness
- Alarm speaker volume
Correct answer: Tidal volume setting
Tidal volume must be verified before use to ensure the patient receives the appropriate breath size and avoid barotrauma or hypoventilation.
Question 2: An infusion pump alarms 'upstream occlusion.' What is the most likely cause?
- Depleted battery
- Kinked IV tubing above the pump (Correct answer)
- Air in the IV line
- Incorrect drug concentration entered
Correct answer: Kinked IV tubing above the pump
An upstream occlusion alarm typically indicates a blockage or kink in the tubing between the fluid bag and the pump, preventing fluid from reaching the pump.
Question 3: What does the term 'duty cycle' refer to in electrosurgical units (ESU)?
- The ratio of on-time to total period of the RF waveform (Correct answer)
- The maximum wattage output the unit can sustain
- The frequency of the cutting waveform
- The number of surgeries performed between servicing
Correct answer: The ratio of on-time to total period of the RF waveform
Duty cycle is the ratio of active (on) time to total cycle time in the RF waveform, which determines whether the ESU operates in cut or coagulation mode.
Question 4: A pulse oximeter reads SpO2 of 98% but the patient appears cyanotic. Which condition could cause this discrepancy?
- Hyperoxia
- Carbon monoxide poisoning (Correct answer)
- Peripheral vasoconstriction
- Hypothermia
Correct answer: Carbon monoxide poisoning
Carbon monoxide binds hemoglobin similarly to oxygen, causing standard pulse oximeters to read falsely high SpO2 even when actual oxygen saturation is dangerously low.
Question 5: Which international standard specifically governs the safety requirements for medical electrical equipment?
- ISO 9001
- IEC 60601-1 (Correct answer)
- ANSI Z136.1
- NFPA 99
Correct answer: IEC 60601-1
IEC 60601-1 is the primary international standard establishing general safety and essential performance requirements for medical electrical equipment.
Question 6: During a defibrillator self-test, the energy readback shows 195 J when 200 J was selected. What is the acceptable tolerance per most standards?
- ±1%
- ±5%
- ±15% (Correct answer)
- ±25%
Correct answer: ±15%
Most defibrillator standards, including AAMI DF80, allow a ±15% tolerance on delivered energy compared to the selected energy setting.
Question 7: A hemodialysis machine's conductivity alarm activates during treatment. What is the immediate corrective action?
- Increase blood flow rate
- Take the patient off bypass and return blood (Correct answer)
- Recalibrate the conductivity probe
- Increase ultrafiltration rate
Correct answer: Take the patient off bypass and return blood
A conductivity alarm indicates an unsafe dialysate concentration; the patient should immediately be taken off bypass and blood returned to prevent electrolyte imbalance.
CABT Medical Equipment Operations 2
Which parameter is most critical to verify before connecting a patient to a mechanical ventilator?