Why Electrolytes Matter — ECG Academy Lesson

Understand how sodium, potassium, calcium, and magnesium drive the cardiac action potential and why abnormal levels produce ECG changes you can see on the monitor.

Learning Objectives

• Identify the four electrolytes most critical to cardiac cell function
• Describe the five phases of the cardiac action potential and which ions dominate each phase
• Explain why electrolyte imbalances alter the ECG waveform
• List common patient populations at risk for electrolyte-related ECG changes
• Define the monitor tech role in recognizing and reporting suspected electrolyte abnormalities