CMT Monitoring Techniques and Equipment 2 — Questions and Answers
Question 1: Which electrode placement is used for a modified chest lead (MCL1) during continuous cardiac monitoring?
- Positive electrode at V1 position, negative at left shoulder (Correct answer)
- Positive electrode at left shoulder, negative at V1 position
- Positive electrode at right arm, negative at left leg
- Positive electrode at V5 position, negative at right shoulder
Correct answer: Positive electrode at V1 position, negative at left shoulder
MCL1 uses the positive electrode at the V1 position (fourth intercostal space, right sternal border) and the negative electrode at the left shoulder.
Question 2: What does a wandering baseline artifact on a cardiac monitor most commonly indicate?
- Atrial fibrillation
- Poor electrode contact or patient movement (Correct answer)
- Ventricular tachycardia
- Lead reversal
Correct answer: Poor electrode contact or patient movement
A wandering baseline is most commonly caused by poor electrode-skin contact, patient movement, or respiratory variation.
Question 3: The gain (sensitivity) setting on a cardiac monitor is typically set to what default value?
- 5 mm/mV
- 10 mm/mV (Correct answer)
- 20 mm/mV
- 2 mm/mV
Correct answer: 10 mm/mV
Standard gain is 10 mm/mV, meaning a 1 mV signal produces a 10 mm deflection on the monitor.
Question 4: Which type of cardiac monitor continuously records and stores cardiac rhythm data that can be retrieved for analysis?
- Holter monitor (Correct answer)
- Event monitor
- Telemetry monitor
- 12-lead ECG machine
Correct answer: Holter monitor
A Holter monitor continuously records cardiac rhythm for 24-48 hours, storing all data for later analysis.
Question 5: When a 60-cycle interference (AC interference) artifact appears on the monitor, what is the most appropriate first action?
- Replace the entire monitoring system
- Check and replace electrodes, ensure proper grounding (Correct answer)
- Increase the filter settings on the monitor
- Reposition the patient
Correct answer: Check and replace electrodes, ensure proper grounding
AC interference is first addressed by checking electrode contact quality and ensuring proper grounding, as loose electrodes are the most common cause.
Question 6: What is the primary purpose of the notch filter on a cardiac monitor?
- Eliminate high-frequency muscle artifact
- Remove 60 Hz electrical interference from power lines (Correct answer)
- Enhance P-wave visibility
- Reduce baseline wander
Correct answer: Remove 60 Hz electrical interference from power lines
The notch filter specifically targets and eliminates 60 Hz interference from AC power lines.
Question 7: During bedside monitoring, the paper speed is typically set at what standard rate?
- 10 mm/sec
- 25 mm/sec (Correct answer)
- 50 mm/sec
- 100 mm/sec
Correct answer: 25 mm/sec
Standard paper speed is 25 mm/sec, which means each small box (1 mm) represents 0.04 seconds.
CMT Monitoring Techniques and Equipment 2
Which electrode placement is used for a modified chest lead (MCL1) during continuous cardiac monitoring?