RMA EKG and Electrocardiography 2 — Questions and Answers
Question 1: Which lead is the standard rhythm strip lead because it usually shows clear, upright P waves and QRS complexes?
- Lead II (Correct answer)
- Lead aVR
- Lead V1
- Lead III
Correct answer: Lead II
Lead II runs parallel to the heart's electrical axis, producing clear upright deflections ideal for rhythm analysis.
Question 2: On standard EKG paper, how much time does one small (1 mm) horizontal box represent?
- 0.04 second (Correct answer)
- 0.20 second
- 0.10 second
- 0.01 second
Correct answer: 0.04 second
At a paper speed of 25 mm/sec, each small box equals 0.04 second.
Question 3: A patient's skin is oily and the electrodes keep losing contact. What should the RMA do first?
- Cleanse the site with alcohol and let it dry (Correct answer)
- Increase the EKG gain
- Apply more electrodes over each other
- Use only three limb leads
Correct answer: Cleanse the site with alcohol and let it dry
Cleansing oily skin with alcohol removes residue so electrodes adhere and conduct properly.
Question 4: Which EKG artifact appears as a thick, fuzzy baseline caused by nearby electrical equipment?
- 60-cycle (AC) interference (Correct answer)
- Wandering baseline
- Somatic tremor
- Standardization artifact
Correct answer: 60-cycle (AC) interference
60-cycle interference comes from alternating current sources and shows as a uniform fuzzy baseline.
Question 5: The chest lead V1 is correctly placed at which location?
- Fourth intercostal space, right sternal border (Correct answer)
- Fifth intercostal space, midclavicular line
- Fourth intercostal space, left sternal border
- Fifth intercostal space, anterior axillary line
Correct answer: Fourth intercostal space, right sternal border
V1 is positioned in the fourth intercostal space just to the right of the sternum.
Question 6: What does the P wave on an EKG represent?
- Atrial depolarization (Correct answer)
- Ventricular depolarization
- Ventricular repolarization
- Atrial repolarization
Correct answer: Atrial depolarization
The P wave reflects depolarization of the atria as the impulse spreads from the SA node.
Question 7: A wandering baseline that drifts up and down is most often caused by what?
- Patient movement or respiration (Correct answer)
- Loose AC power cord
- Dried electrode gel only
- Excessive paper speed
Correct answer: Patient movement or respiration
Patient movement and breathing shift the baseline, producing a slow wavering drift.
RMA EKG and Electrocardiography 2
Which lead is the standard rhythm strip lead because it usually shows clear, upright P waves and QRS complexes?