Medical Surgical Potassium K+ #16

Question

The nurse provides care for a client with a serum potassium level of 5.4 mEq/L. Which finding should the nurse expect on the client’s electrocardiogram (ECG)?

Answers

  1. ST depression
    • Rationale:

      This answer is not correct because ST depression, or sagging, is expected with hypokalemia, not hyperkalemia. Early ECG changes associated with hyperkalemia include tall, peaked T waves with a narrow base in addition to flat P waves, prolonged PR intervals, and widened QRS complexes.

  2. Inverted T wave
    • Rationale:

      This answer is not correct because an inverted or depressed T wave is expected with hypokalemia, not hyperkalemia. Early ECG changes associated with hyperkalemia include tall, peaked T waves with a narrow base in addition to flat P waves, prolonged PR intervals, and widened QRS complexes.

  3. Prominent U wave
    • Rationale:

      This answer is not correct because a prominent, or elevated U wave is expected with hypokalemia, not hyperkalemia. Early ECG changes associated with hyperkalemia include tall, peaked T waves with a narrow base in addition to flat P waves, prolonged PR intervals, and widened QRS complexes.

  4. Tall peaked T waves
    • Rationale:

      This answer is correct because hyperkalemia can cause the client to experience tall, peaked T waves; therefore, this finding is expected based on the client’s current serum potassium level.

Overview

Potassium is a mineral and electrolyte that plays an important role in both nerve conduction and muscle contraction. Hyperkalemia increases the client’s risk for arrhythmias which is potentially life-threatening.

Explanation

Learning Outcomes

The normal range for serum potassium within the body is 3.5 to 5 mEq/L. When the client’s serum potassium level is greater than 5 mEq/L, hyperkalemia is diagnosed. Hyperkalemia increases the client’s risk for arrhythmias which is potentially life-threatening. Early ECG changes associated with hyperkalemia include tall, peaked T waves with a narrow base in addition to flat P waves, prolonged PR intervals, and widened QRS complexes.

Test Taking Tip

Consider the impact of hyperkalemia on the cardiovascular system to answer this question correctly.

Video Rationale