Question

Which of the following methods should an EKG technician use to calculate a patient's heart rate from the EKG tracing?

a. Calculate the mean rate and divide 1,500 by that rate
b. Count the number of small boxes in two cardiac cycles
c. Divide 300 by the number of large boxes between two R waves
d. Count the number of large boxes between P and T waves

Answer 1

To calculate heart rate from an EKG, divide 300 by the number of large boxes between two R waves. This method is simple and assumes a constant time between beats, providing an estimate of the heart rate on a regular rhythm ECG.

Step-by-step explanation:

To calculate a patient's heart rate from an EKG tracing, an EKG technician should use the method of dividing 300 by the number of large boxes between two R waves. The steps for calculating the heart rate using the EKG are as follows:

1. Identify the R waves, which are the tall, sharp peaks that represent ventricular depolarization.
2. Count the number of large boxes between two consecutive R waves to measure the R-R interval.
3. Divide 300 by the number of large boxes you counted. This is because one large box on the EKG paper represents 0.2 seconds and there are five large boxes per second, making the rate 300 boxes per minute.

This method assumes a constant R-R interval (constant time between beats). It is one of the most commonly used and simplest methods for estimating the heart rate on a regular rhythm ECG.