Electrolytes
What are electrolytes, and where are they found?
Minerals that conduct electricity; found in blood, urine, tissues, and body fluids.
What percentage of the body is made up of water?
50–65% (about one-half to two-thirds).
What is a crystalloid solution?
IV solution with small particles that move between the bloodstream and tissues.
What is acidosis?
Too much acid in the blood; pH below normal.
What does intake and output (I&O) measure?
Fluid taken in and excreted; helps monitor balance.
Name two key functions of electrolytes in the body.
Balance fluid and pH, move nutrients/waste, and help muscles and nerves work.
What hormone helps the kidneys conserve water?
Vasopressin (Antidiuretic Hormone, ADH).
Define tonicity.
The ability of a solution to cause water movement into or out of cells.
What is alkalosis?
Too little acid; blood becomes too basic.
How often should I&O be documented?
At least every 8 hours or per facility policy.
What are the normal ranges for sodium (Na⁺) and potassium (K⁺)?
Na⁺: 135–145 mEq/L; K⁺: 3.5–5.1 mEq/L.
What is hypovolemia and what can cause it?
Decreased blood volume due to fluid loss (e.g., burns, diuretics, vomiting).
What does a hypotonic solution do?
Moves water from extracellular space into cells.
Give two causes of metabolic acidosis.
Kidney failure, uncontrolled diabetes, severe dehydration, and lactic acidosis.
Name two signs of fluid overload.
Edema, dyspnea, bounding pulse, high BP.
What happens in hypernatremia vs. hyponatremia?
Hypernatremia: excess sodium → dehydration; Hyponatremia: low sodium → confusion, cramps.
List two signs of hypovolemic shock.
Rapid pulse, low BP, pale skin, confusion, little or no urine output.
What does a hypertonic solution do?
Draws water out of cells into extracellular space.
List two causes of metabolic alkalosis.
Vomiting, diuretics, antacid overuse.
What should a nurse monitor during IV therapy?
Site condition, flow rate, patient response, lab values.
Describe symptoms of hypokalemia and hyperkalemia.
Hypokalemia: muscle weakness, arrhythmia; Hyperkalemia: cardiac arrest risk, peaked T waves.
What causes hypervolemia and how is it treated?
Kidney failure or excess fluids; treatment—diuretics, fluid restriction.
When is whole blood given instead of packed RBCs?
In major trauma or surgery with significant blood loss, volume needs to be replaced.
Differentiate respiratory acidosis vs. alkalosis.
Acidosis: CO₂ retention (COPD); Alkalosis: CO₂ loss (hyperventilation).
What are two nursing actions for hypovolemia?
Administer fluids, monitor vitals, report low output, and elevate legs.