NCLEX-PN

STEP 3: ANALYZE “P” WAVES The “P” wave represents atrial depolarization . In normal sinus rhythm the “P” wave is always positive in lead II and always negative in lead aVR. Questions yourself the following questions:

●​ Are “P” waves present? ●​ Are they round and upright in appearance? ●​ Are they consistent or do they change in appearance throughout the strip? STEP 4: MEASURE THE PR INTERVAL

The PR interval (PRI) measures from the beginning of the “P” wave to the beginning of the “QRS” complex which measures the time of depolarization of the atria to depolarization of the ventricles and reflects a physiological delay in AV conduction imposed by the AV node. Normal range is 120 – 200 ms or 0.12 to 0.20 seconds. Questions to ask in this step are as followed: ●​ What is the length of the “PRI”? ●​ Is the PRI consistently the same length throughout the strip? (gradually increasing?)

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