Archer Renal and Nutrition Practice Test 2025 – Complete Exam Prep

In a client with a potassium level of 5.6 mEq/L, which indicates mild hyperkalemia, the cardiac rhythm often manifests as narrow and peaked T-waves on an electrocardiogram (ECG). Elevated potassium levels can affect cardiac conduction and repolarization, leading to changes in the ECG tracing.

The reason why narrow and peaked T-waves occur is that high potassium levels alter the electrical activity of the heart. Specifically, elevated serum potassium can increase the rate of repolarization, causing the T-waves to become taller and more pointed. This change occurs in an attempt to maintain cardiac function in the presence of disturbed electrolyte balance.

While other ECG changes related to potassium may include issues like wide QRS complexes or changes in the PR interval, these are typically associated with higher levels of hyperkalemia. In this case, since the potassium level is only moderately elevated, the characteristic change observed is primarily the peaked T-waves. Recognizing these changes is crucial in managing patients, as they can indicate a risk for more severe cardiac events if potassium levels continue to rise.