DC Safety & Infection Control 2 — Questions and Answers
Question 1: Which current level is considered the threshold for ventricular fibrillation via microshock in a patient with an intracardiac catheter?
- 100 mA
- 10 mA
- 100 µA
- 10 µA (Correct answer)
Correct answer: 10 µA
As little as 10 microamperes (µA) delivered directly to the myocardium can induce ventricular fibrillation via microshock.
Question 2: When applying ECG monitoring electrodes, which action best prevents skin breakdown and artifact in a patient on contact precautions?
- Reuse electrodes from the previous shift to minimize waste
- Don gloves, prepare skin thoroughly, and use single-patient electrodes (Correct answer)
- Apply electrodes over clothing to avoid skin contact
- Share electrode packages between patients in the same isolation room
Correct answer: Don gloves, prepare skin thoroughly, and use single-patient electrodes
Gloving, proper skin preparation, and dedicated single-patient electrode sets prevent both infection transmission and skin injury.
Question 3: A telemetry transmitter from a patient on droplet precautions must be cleaned. Which disinfectant is most appropriate for most ECG/telemetry equipment?
- Glutaraldehyde soak for 30 minutes
- EPA-registered hospital-grade disinfectant wipe per manufacturer instructions (Correct answer)
- Isopropyl alcohol 100% immersion
- Autoclave sterilization
Correct answer: EPA-registered hospital-grade disinfectant wipe per manufacturer instructions
EPA-registered hospital-grade disinfectant wipes used per manufacturer guidance are the standard for surface-level disinfection of telemetry equipment.
Question 4: A nurse notices a cardiac monitor's power cord has frayed insulation. The correct immediate action is to:
- Wrap the frayed area with electrical tape and continue use
- Remove the device from service and tag it for biomedical engineering (Correct answer)
- Reduce patient contact time with the device
- Increase the ground fault circuit interrupter sensitivity
Correct answer: Remove the device from service and tag it for biomedical engineering
Damaged electrical equipment must be immediately removed from service and tagged for biomedical engineering to prevent macroshock injury.
Question 5: Which of the following isolation precaution types would be required for a patient admitted with suspected COVID-19 who requires continuous cardiac monitoring?
- Contact precautions only
- Droplet precautions only
- Airborne plus contact precautions (Correct answer)
- Standard precautions only
Correct answer: Airborne plus contact precautions
COVID-19 requires airborne and contact precautions; monitoring equipment must be dedicated to that patient and staff must wear appropriate PPE including an N95.
Question 6: In the context of cardiac monitoring, 'ground fault isolation' on a bedside monitor primarily protects against:
- Radio frequency interference
- Microshock from stray leakage current reaching the patient (Correct answer)
- Overvoltage damage to the display
- Electrode lead wire corrosion
Correct answer: Microshock from stray leakage current reaching the patient
Ground fault isolation circuits limit stray leakage current, protecting susceptible patients (especially those with intracardiac lines) from microshock.
Question 7: After performing defibrillation on a patient in ventricular fibrillation, the nurse should clean reusable defibrillator paddles by:
- Autoclaving between each use
- Wiping with an approved disinfectant per manufacturer and facility policy before next patient use (Correct answer)
- Rinsing with sterile water only
- Air-drying without wiping because electricity sterilizes the paddles
Correct answer: Wiping with an approved disinfectant per manufacturer and facility policy before next patient use
Reusable paddles must be cleaned with an approved disinfectant per manufacturer instructions after each patient use to prevent cross-contamination.
DC Safety & Infection Control 2
Which current level is considered the threshold for ventricular fibrillation via microshock in a patient with an intracardiac catheter?