CCT Resting ECG Procedures 2

Question 1

What is the correct intercostal space and anatomical location for electrode V4?

Accepted Answer

5th intercostal space at the midclavicular line

Answer

4th intercostal space at the right sternal border

Answer

4th intercostal space at the left sternal border

Answer

5th intercostal space at the anterior axillary line

Question 2

During a resting ECG, a patient continues to shiver despite being asked to relax. What is the most likely artifact that will result, and how can it be minimized?

Accepted Answer

Muscle tremor artifact (rapid, irregular oscillations obscuring the baseline); warm the patient with a blanket and re-attempt

Answer

60 Hz interference; disconnect all IV pumps

Answer

Wandering baseline; have the patient breathe faster

Answer

Motion artifact; strap the patient's limbs to the table

Question 3

A technician is performing an ECG on a morbidly obese patient and finds it difficult to identify the sternal angle. What is the best approach to locating the correct intercostal spaces?

Accepted Answer

Palpate the sternum from the top to find the manubriosternal junction (sternal angle/angle of Louis) and count ribs methodically from that landmark

Answer

Estimate placement based on visual inspection of the chest shape

Answer

Place electrodes at equal-distance intervals across the chest

Answer

Ask the patient which area of the chest feels most central

Question 4

Which of the following ECG findings is an artifact rather than a true cardiac finding?

Accepted Answer

A perfectly regular, high-frequency oscillation at 60 Hz (AC interference) superimposed on all leads

Answer

ST elevation in leads II, III, and aVF

Answer

P waves that are absent in all leads

Answer

A prolonged QTc interval of 550 ms

Question 5

When is it appropriate to use the 'half-standardization' (5 mm/mV) setting on an ECG machine?

Accepted Answer

When QRS complexes are so tall that they overlap adjacent leads, making interpretation impossible at standard gain

Answer

When QRS voltage is very low and complexes are hard to see

Answer

In all pediatric patients as a standard practice

Answer

When the patient has a slow heart rate requiring larger waveforms

Question 6

What is the purpose of the Wilson Central Terminal in ECG recording?

Accepted Answer

It creates a reference zero potential by connecting the right arm, left arm, and left leg electrodes through resistors, serving as the negative reference for unipolar leads

Answer

It amplifies the ECG signal to improve readability

Answer

It is the ground electrode that prevents electrical shock to the patient

Answer

It filters out low-frequency baseline wander from the ECG signal