*Master EKG interpretation for the NCLEX exam with these 5 easy steps: *

The first step in EKG interpretation is determining the regularity (also known as the rhythm) of the strip. This should be done by using the R waves. For clarification on where to locate the R waves in an EKG strip, refer to the article written here. The regularity of an EKG strip can be determined using one of two techniques.

- The first technique can be done using an index card. Start at the left side of the rhythm strip and place the index card above the first two R-waves. Using a sharp pencil or pen, mark the index card above the two R waves. Continue to measure from R wave to R wave across the rhythm strip. If each width is the same same, it is a regular rhythm. However, if there is any variation, make sure to mark it on the index card. If the distance varies by 0.12 seconds (3 small squares) or more between the shortest and longest R wave variation marked, the rhythm is irregular.
^{[1]} - The second technique can be done using calipers rather than an index card. The calipers can be used to measure the regularity of the R wave in the same way as the index card, by placing the tip of the two caliper points on top of two consecutive R waves and proceeding left to right across the rhythm strip.
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The second step in EKG interpretation is calculating the heart rate. This step can also be performed in one of two ways.

*Quick, approximate heart rate calculation*- Count the number of R waves in a 6-second strip, then multiply that number by 10. This technique can be used on regular and irregular rhythms.*Longer, precise heart rate calculation -*Count the number of small squares between two consecutive R waves. Divide that number into 1500. This technique determines the rate for regular rhythms.

Step 3: Examine the P waves

When examining the P waves, make sure all criteria are met:

- All P waves are identical in size, shape, and position
- There is one P wave to each QRS complex.

Step 4: Measure the PR interval

Determine the PR interval by measuring from the beginning of the P wave (as it leaves the baseline) and to the beginning of the QRS complex. (Learn more about the PR interval here). Count the number of small squares within the interval then multiply by 0.04 seconds.

Step 5: Measure the QRS complex

Determine the QRS complex by measuring from the beginning of the Q (as it leaves the baseline) and to the end of the S. ^{[1] }(Learn more about the QRS complex here). Count, the number of small squares within the interval then multiply by 0.04 seconds.

References

- Huff, J. (2012).
*ECG workout: Exercises in arrhythmia interpretation*(6th ed.). Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins.

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