ECG Question #9


A nurse on the telemetry unit is caring for a client with a potassium of 5.6 mEq/L. The nurse anticipates changes in the ECG which would include the following finding:


  1. A prolonged QT interval
    • Rationale:
  2. Delayed SA note impulse activity
    • Rationale:
  3. Peaked T waves
    • Rationale:
  4. Inverted U wave
    • Rationale:



A peaked T wave is represented as repolarization of the ventricles. Serum potassium levels may cause the T wave to become peaked and tall. An elevated serum potassium level does not prolong the QT interval, delay the impulse traveling from the SA node, or invert the U wave.

Learning Outcomes

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