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Based on Fundamentals of Nursing (Yoost & Crawford, 3rd ed., 2023) and
Galen College of Nursing NSG 3100 Unit 10: Electrolytes PowerPoint
Laboratory values reflect Galen Standardized Values of Nursing
Disclaimer: These notes are an unofficial study resource created by Kamri Stewart.
They are not affiliated with or endorsed by Galen College of Nursing.
Use alongside your textbooks, lectures, and official class materials.
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Sodium (Na⁺) ............................................................................................................... 2
Potassium (K⁺) ............................................................................................................. 5
Calcium (Ca²⁺) ............................................................................................................. 6
Magnesium (Mg²⁺) ........................................................................................................ 8
Chloride (Cl⁻) ............................................................................................................. 10
Phosphate (PO₄³⁻) ...................................................................................................... 12
, Sodium (Na⁺)
➢ Normal Range
o 35–145 mEq/L
➢ What It Is
o Sodium is the main positively charged ion (cation) found outside cells
(extracellular). It helps regulate fluid balance, blood pressure, and electrical
signals in nerves and muscles.
Key Terms
➢ Cation: A positively charged ion
➢ Extracellular: Located outside the cells
➢ Osmolality: The concentration of dissolved particles in body fluids; affects water
movement
➢ SIADH: Syndrome of Inappropriate Antidiuretic Hormone — causes water retention
and dilution of sodium
➢ OC: Level of consciousness
Hyponatremia (Low Sodium)
➢ Definition
o Sodium <135 mEq/L
➢ Causes
o Diuretics
o Vomiting
o SIADH
o Water intoxication
➢ Symptoms
o Confusion
o Nausea
o Seizures
o Muscle cramps
➢ Dietary Support
o Salted crackers
o Broth
o Processed foods
➢ IV Fluids