ECG ECG Troubleshooting 1 — Questions and Answers
Question 1: What is the most common cause of a wandering baseline on an ECG?
- Patient movement or poor electrode contact (Correct answer)
- A cardiac arrhythmia
- Equipment malfunction
- Electromagnetic interference
Correct answer: Patient movement or poor electrode contact
Wandering baseline is most commonly caused by patient movement, respiratory motion, or poor electrode-skin contact. Proper skin preparation and electrode placement minimize this artifact.
Question 2: What should you do if the ECG shows 60-cycle (60 Hz) interference?
- Check for nearby electrical equipment and ensure proper grounding (Correct answer)
- Replace the ECG machine
- Repeat the ECG tomorrow
- Increase paper speed
Correct answer: Check for nearby electrical equipment and ensure proper grounding
60 Hz interference creates a thick, fuzzy baseline caused by nearby electrical equipment. Solutions include ensuring proper grounding, unplugging nearby devices, and checking cable integrity.
Question 3: Why is skin preparation important before applying ECG electrodes?
- To reduce impedance and improve signal quality (Correct answer)
- To sterilize the skin for a procedure
- To make electrode removal easier
- To prevent allergic reactions
Correct answer: To reduce impedance and improve signal quality
Cleaning the skin with alcohol and lightly abrading removes oils, dead skin cells, and debris that increase electrical impedance, resulting in cleaner ECG signals.
Question 4: What happens if limb lead electrodes are placed on the wrong limbs?
- The ECG tracing will show incorrect or inverted waveforms (Correct answer)
- Nothing, the machine compensates automatically
- The machine will not turn on
- Only the heart rate will be affected
Correct answer: The ECG tracing will show incorrect or inverted waveforms
Incorrect lead placement produces misleading ECG patterns that can mimic pathology, such as lead reversal producing apparent axis deviation or inverted complexes.
Question 5: How can you distinguish artifact from true ventricular fibrillation?
- Check the patient's pulse and consciousness level (Correct answer)
- Look only at the monitor
- Increase the paper speed
- Apply more electrodes
Correct answer: Check the patient's pulse and consciousness level
Always assess the patient clinically. If the patient is awake and responsive with a chaotic-looking ECG, it's likely artifact. True V-fib causes immediate loss of consciousness and pulse.
Question 6: What is the significance of lead reversal on a 12-lead ECG?
- It can mimic pathological conditions and lead to misdiagnosis (Correct answer)
- It has no clinical significance
- It only affects the heart rate display
- It automatically triggers an alarm
Correct answer: It can mimic pathological conditions and lead to misdiagnosis
Lead reversal can produce ECG patterns that mimic pathology such as dextrocardia, lateral MI, or right axis deviation, potentially leading to unnecessary interventions.
ECG ECG Troubleshooting 1
What is the most common cause of a wandering baseline on an ECG?