The following steps should be used during any ECG Rhythm Analysis:
1. Look at the QRS Complexes – Are they regular or irregular? You can feel the patient’s pulse while you do this and see that the patient has a regular or irregular pulse and that this matches up with what you are seeing on the ECG or EKG if you’re in the US.
2. Determine the rate by counting the QRS Complexes in a 10 second strip. Is it fast (greater than 100 beats per minute), Normal (60-100 beats per minute) or slow (less than 60 beats per minute)?
3. Look at the P- Waves. Are they normal? A normal P wave should be upright in lead II and should be identical to all the other P waves in the ECG. A P wave should also precede a QRS Complex. If you can’t see a P-wave, the person most likely has Atrial Fibrillation – (see if this is normal for the patient, or a new condition).
4. Look at the PR interval and the relationship between the P-Waves and the QRS Complexes. A PR interval should normally be between 0.12 and 0.20 seconds in length. If it is longer than this, there is a conduction problem between the SA node and the AV node. If it is shorter than this, the SA node is firing too quickly as is the case in Atrial Tachycardia.
5. Look at the RR intervals – are they regular? Are they identical in timings? In a normal sinus rhythym an RR wave should be consistent.
6. Look at the QRS Complexes – It is normally less than 0.1 seconds in length. If this is longer, there is a conduction problem between the AV Node and the Perkinje Fibres (this indicates a Bundle Branch Block).
Steps in ECG Analysis
By following these steps, the basic ECG rhythm can be interpreted.
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