Clinical meaning
Potassium is the primary intracellular cation critical for maintaining cardiac electrical stability. Normal serum potassium ranges from 3.5-5.0 mEq/L. Hyperkalemia (>5.0 mEq/L) causes decreased resting membrane potential, leading to initial increased excitability followed by decreased conduction velocity. ECG changes progress from peaked T waves to widened QRS to sine wave pattern and cardiac arrest. Hypokalemia (<3.5 mEq/L) hyperpolarizes the cell membrane, causing flattened T waves, U wave appearance, ST depression, and increased risk of torsades de pointes. Cardiovascular complications can rapidly progress to hemodynamic instability and organ failure. The RPN/LVN must monitor vital signs frequently, recognize early signs of decompensation such as changes in heart rate, blood pressure, and peripheral perfusion, and escalate concerns promptly. Electrocardiographic changes may provide early warning of cardiac compromise before clinical symptoms become apparent. Within the RPN/LVN scope of practice, nursing care for hyperkalemia vs hypokalemia - ecg changes & cellular physiology includes systematic assessment, implementation of established care protocols, accurate documentation, and timely communication with the interprofessional team. The practical nurse contributes to patient safety through ongoing monitoring, patient education reinforcement, and adherence to...