Question

Which of the following methods should an egg tech use to calculate a patients heart rate from the leg tracing?

1. calculate the mean rate and divide 1500 by that rate
2. count the number of small boxes in two cardiac cycles
3. Divide 300 by the number of large boxes between two r waves
4. count the number of large boxes between p and t waves

Answer 1

Final answer:

To calculate the heart rate from an ECG tracing, divide 300 by the number of large boxes between two R waves, assuming a standard paper speed of the ECG. The correct option is 1.

Step-by-step explanation:

To calculate a patient's heart rate from an ECG tracing, the correct method is to divide 300 by the number of large boxes between two R waves. This is based on the assumption that the ECG paper speed is the standard 25 mm/s, and the large boxes are equivalent to 0.20 seconds.

The method works because there are five large boxes per second, and 60 seconds in a minute, so 300 large boxes are equivalent to 1 minute. Therefore, if you count the number of large boxes between consecutive R waves, dividing 300 by this number gives the heart rate in beats per minute (bpm). The correct option is 1.