BCIT - 7150 - SYSTEMATIC ECG ANALYSIS UPDATED
ACTUAL QUESTIONS AND CORRECT ANSWERS
Question:
1. How to interpret strips (Steps)
Answer:
- Calculate HR (ventricular & atrial)
- Determine rhythm (regular/irregular)
- Examine P wave
- Look at PR interval
- Look at QRS complex
- Look at ST segment
- Look at T wave
- Analyse QT interval
- Interpret the rhythm
- Determine problems of conduction
- Describe possible cause
- Implications for O2 supply & demand
- Choose an appropriate intervention
Question:
2. What is the six-second method?
Answer:
- ECG paper is printed with 3-second markers on the top or bottom of the page
- To calculate the HR count the number of QRS complexes in a 6-sec period and
multiply by 10
Question:
3. Methods for calculating the HR on a strip
Answer:
1) the six-second method (least accurate)
2) the sequence method
3) the ruler method (ventricular and atrial)
4) the large square method
5) the small square method
, Question:
4. What is the sequence method?
Answer:
- Select an R wave that falls on a dark vertical line (see below).
- number the NEXT 6 consecutive dark vertical lines w/ 300, 150, 100, 75, 60, 50
- Note where the next R wave falls in relation to the numbers - that is the heart
rate
Question:
5. What is the ruler method?
Answer:
1) place the ruler on the ECG strip (see example).
2) Place the arrow (found on the ruler) on a QRS complex.
3) Measure the third (on some rulers it's the second) QRS complex from the arrow
= ventricular rate.
Question:
6. What is the large square method?
Answer:
- count the number of large squares between R waves
- divide number of squares by 300 = HR
Question:
7. What is the small square method?
Answer:
- count the number of small squares between r waves
- divide number of squares by 1500 = HR
Question:
8. How to calculate rhythm
Answer:
- Select an R wave at the beginning of the strip.
- Place one tip of the caliper on that R wave and the other tip on the next R wave.
- Compare each of the R‑R intervals along the strip without changing the distance
between the tips of the calipers.
- if the ratios are = then the rhythm is REGULAR (slightly off is okay too less than
.16)
ACTUAL QUESTIONS AND CORRECT ANSWERS
Question:
1. How to interpret strips (Steps)
Answer:
- Calculate HR (ventricular & atrial)
- Determine rhythm (regular/irregular)
- Examine P wave
- Look at PR interval
- Look at QRS complex
- Look at ST segment
- Look at T wave
- Analyse QT interval
- Interpret the rhythm
- Determine problems of conduction
- Describe possible cause
- Implications for O2 supply & demand
- Choose an appropriate intervention
Question:
2. What is the six-second method?
Answer:
- ECG paper is printed with 3-second markers on the top or bottom of the page
- To calculate the HR count the number of QRS complexes in a 6-sec period and
multiply by 10
Question:
3. Methods for calculating the HR on a strip
Answer:
1) the six-second method (least accurate)
2) the sequence method
3) the ruler method (ventricular and atrial)
4) the large square method
5) the small square method
, Question:
4. What is the sequence method?
Answer:
- Select an R wave that falls on a dark vertical line (see below).
- number the NEXT 6 consecutive dark vertical lines w/ 300, 150, 100, 75, 60, 50
- Note where the next R wave falls in relation to the numbers - that is the heart
rate
Question:
5. What is the ruler method?
Answer:
1) place the ruler on the ECG strip (see example).
2) Place the arrow (found on the ruler) on a QRS complex.
3) Measure the third (on some rulers it's the second) QRS complex from the arrow
= ventricular rate.
Question:
6. What is the large square method?
Answer:
- count the number of large squares between R waves
- divide number of squares by 300 = HR
Question:
7. What is the small square method?
Answer:
- count the number of small squares between r waves
- divide number of squares by 1500 = HR
Question:
8. How to calculate rhythm
Answer:
- Select an R wave at the beginning of the strip.
- Place one tip of the caliper on that R wave and the other tip on the next R wave.
- Compare each of the R‑R intervals along the strip without changing the distance
between the tips of the calipers.
- if the ratios are = then the rhythm is REGULAR (slightly off is okay too less than
.16)
