Calculating the Heart Rate

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Learning Objectives:

 

1. Calculate the heart rate using the Box Method and Division Method

 

Calculating the rate in an ECG is an important as identifying the rhythm itself as it bears implication to the treatment. Although various methods are available, for simplicity and practicality only 2 methods will be introduced here.

 

The Box Method


1. Find a R wave that lands on a heavy line

2. Place the following value on succeeding heavy line as done in the diagram below






3. If the next R wave falls on a heavy line assigned the appropriate rate value to it.

4. If however the next R wave falls between 2 heavy lines, take the difference between the 2 value and divide by 5. Each of the small square is then worth that quotient.

 

The Division Method

1) Count the number of large boxes between 2 R waves

2) Divide that number by 300, and assign that as the approximate rate.

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