ECG ECG Patient Monitoring and Safety 2 — Questions and Answers
Question 1: Which AHA monitoring category applies to patients who are in the first 48 hours after acute MI?
- Class I (monitoring indicated) (Correct answer)
- Class II (monitoring of uncertain benefit)
- Class III (monitoring not indicated)
- Class IV (monitoring contraindicated)
Correct answer: Class I (monitoring indicated)
The AHA designates continuous cardiac monitoring as Class I (clearly indicated) during the first 48 hours after acute MI.
Question 2: What is the recommended ECG lead for detecting ST-segment changes in the anterior wall of the left ventricle?
- V4 or V5 (Correct answer)
- Lead II
- aVL
- V1
Correct answer: V4 or V5
V4 and V5 provide the best sensitivity for detecting anterior wall ST changes during ischemia monitoring.
Question 3: A patient's ECG shows a sudden straight line. What is the FIRST action the nurse should take?
- Check the patient and verify lead connections before assuming asystole (Correct answer)
- Begin CPR immediately
- Call a code blue
- Administer epinephrine
Correct answer: Check the patient and verify lead connections before assuming asystole
A flat line on a monitor most often reflects a loose lead or electrode, not asystole; always assess the patient first.
Question 4: What does 'signal-averaged ECG' (SAECG) primarily detect?
- Late potentials indicating risk for ventricular arrhythmias (Correct answer)
- P-wave morphology changes
- QT interval prolongation
- ST-segment elevation patterns
Correct answer: Late potentials indicating risk for ventricular arrhythmias
SAECG detects ventricular late potentials, which indicate areas of slow conduction predisposing to re-entrant ventricular arrhythmias.
Question 5: Which condition requires telemetry monitoring according to AHA Class II guidelines?
- Newly diagnosed heart failure with reduced ejection fraction (Correct answer)
- Post-op hernia repair in a healthy 30-year-old
- Stable angina with no recent change in symptoms
- Isolated hypertension without cardiac history
Correct answer: Newly diagnosed heart failure with reduced ejection fraction
New heart failure with reduced ejection fraction carries risk of arrhythmias, making it an AHA Class II monitoring indication.
Question 6: What is the purpose of the QTc (corrected QT) interval calculation in monitoring?
- To adjust QT for heart rate and identify prolongation risk for torsades de pointes (Correct answer)
- To measure P-wave duration accurately
- To detect ST changes independent of rate
- To calculate left ventricular ejection fraction
Correct answer: To adjust QT for heart rate and identify prolongation risk for torsades de pointes
QTc corrects the QT interval for heart rate, allowing standardized assessment of prolongation risk for fatal arrhythmias.
ECG ECG Patient Monitoring and Safety 2
Which AHA monitoring category applies to patients who are in the first 48 hours after acute MI?