Question

You are preparing to perform an ECG on a young woman when she tells you that she just

had her blood tested and her blood potassium level is very low. What might you expect to see on
the ECG tracing as a result of this?

Answer 1

Low potassium levels in the blood, or hypokalemia, can lead to notable ECG changes such as flattened T waves, appearance of U waves, ST segment depression, prolonged PR interval, and potentially prolonged QT interval, which are indicative of disturbances in the heart's electrical activity.

Step-by-step explanation:

An electrocardiogram (ECG) may reflect abnormalities associated with hypokalemia, a condition characterized by an abnormally low potassium blood level. When potassium levels are low, one might expect to see flattened T waves, U waves, ST segment depression, and potentially a prolonged PR interval or QT interval on the ECG tracing. These changes occur because potassium is a crucial electrolyte that helps regulate heart muscle function.

Potassium impacts the electrical activity of the heart, influencing the repolarization and depolarization processes that result in the generation of ECG waveforms. A decrement in potassium levels can diminish the amplitude of the T wave and cause other characteristic changes in the ECG. Comparing current ECGs to older ones assists in identifying such abnormalities, as noted by changes in various intervals and segments. Without normal levels of potassium, the heart's rhythm may become irregular, and there could be a predisposition to arrhythmias.