Which of the following electrolytes plays a crucial role in regulating the excitability of nerve and muscle cells, and its imbalance can lead to cardiac arrhythmias?

A Sodium
B Potassium ✓
C Calcium
D Magnesium

Explanation

Potassium plays a crucial role in regulating the excitability of nerve and muscle cells. Its imbalance can lead to cardiac arrhythmias, muscle weakness, and respiratory failure. Hypokalemia (low potassium) can cause cardiac arrhythmias, while hyperkalemia (high potassium) can lead to cardiac arrest.

Mnemonic

POTASSIUM - Protects Organs Through Action Stimulating Synergistic Ionic Union Maintaining

Source

Berne and Levy Physiology
Electrolytes and Acid-Base Balance Physiology Electrolyte Balance Medium MEDICAL Confidence: high