Hyperkalemia is most likely to cause which clinical concern?

• A. Seizures.
• B. Muscle cramps.
• C. Cardiac conduction problems.
• D. Bruising.

Answer: (C)

Hyperkalemia disrupts the heart’s electrical system. When potassium builds up outside cells, the resting membrane potential becomes less negative and sodium channels don’t recover as well, slowing the spread of impulses through the conduction pathways. This makes the heart conduction slower and more prone to dangerous rhythms, so the most likely and clinically important concern is cardiac conduction problems that can progress to arrhythmias or arrest if not treated. Seizures and bruising aren’t typical direct effects of high potassium, and cramps are more characteristic of other electrolyte issues; the heart’s conduction disturbance is the primary risk with elevated potassium.