Lecture Notes: Five-Step Method to Interpreting EKGs

Presenter: Nicole Weaver

• Background: 10 years of experience as a nurse, specializing in ICU and emergency departments.
• Objective: Teach a simplified method to interpret EKGs by understanding normal sinus rhythm and identifying abnormalities.

Introduction to EKG Interpretation

• Focus on recognizing normal sinus rhythm to easily identify abnormalities.
• Strategy: Learn what's different in abnormal rhythms rather than memorizing all criteria.

Five-Step Method

Step 1: Determine Regularity

• Regular Rhythm: Equal spacing between QRS complexes.
• Methods to Determine Regularity:
  • Paper Method: Mark QRS complexes on paper and align with EKG graph.
  • Box Counting Method: Count small boxes between QRS complexes.
    • Consistent count (e.g., 20, 21, 20, 20) signifies regular rhythm.
    • Inconsistent count (e.g., 20, 38, 22, 42) indicates irregularity.

Step 2: Check the Rate

• Normal Heart Rate: 60 to 100 beats per minute (bpm).
• Methods to Determine Rate:
  • Six-Second Strip Method: Count QRS complexes in six seconds and multiply by 10.
    • Example: 7 beats in six seconds = 70 bpm.
  • 1500 Method: Count small boxes between QRS and divide 1500 by that number.
    • Example: 1500 divided by 22 boxes = 68 bpm.
  • Note: For irregular rhythms, use a six-second strip or full minute count.

Step 3: Assess P to QRS Ratio

• Normal Ratio: 1:1, one P wave for every QRS complex.
• Abnormal Ratios: Multiple P waves for fewer QRS complexes indicate a problem.

Step 4: Evaluate QRS Complex

• Normal Width: Less than 0.12 seconds (three small boxes).
• Wider QRS: Indicates potential issues.

Step 5: Examine PR Interval

• Normal Duration: Less than 0.20 seconds.
• Longer PR Interval: Suggests heart block issues.

Recap of Normal Sinus Rhythm

• Regular rhythm.
• Rate between 60-100 bpm.
• P to QRS ratio of 1:1.
• Narrow QRS complex (< 0.12 seconds).
• Normal PR interval (< 0.20 seconds).

Conclusion

• Emphasis on understanding normal to easily spot abnormalities.
• Encouragement for nurses: "You're not alone in this. Happy nursing."