NCLEX Fluid, Electrolyte, and IV Therapy

Normal Sodium (Na+) Range

135 - 145 mEq/L

Normal Potassium (K+) Range

3.5 - 5.0 mEq/L

Normal Calcium (Ca2+) Range

8.5 - 10.5 mg/dL

Normal Magnesium (Mg2+) Range

1.5 - 2.5 mEq/L

Normal Phosphate (PO4^3-) Range

2.5 - 4.5 mg/dL

Normal Chloride (Cl-) Range

96 - 106 mEq/L

Hypernatremia Hallmark Signs

Intense thirst, dry mucous membranes, confusion, lethargy, agitation, and neurologic dysfunction.

Severe Hyponatremia Signs (

New-onset seizures, acute confusion, cerebral edema, coma, and respiratory arrest.

Hyperkalemia ECG & Cardiac Signs

Cardiac dysrhythmias, tall peaked T waves, widened QRS, and potential cardiac arrest.

Hypokalemia ECG Signs

Flattened T waves, ST depression, and prominent U waves.

Potassium IV Administration Rule

NEVER administer IV push or bolus; always dilute and use an infusion pump.

Positive Trousseau Sign

Carpopedal spasm induced by inflating a BP cuff above systolic pressure for 3 minutes.

Positive Chvostek Sign

Facial muscle twitching elicited by tapping over the facial nerve in front of the ear.

Hypercalcemia Presentation

Decreased neuromuscular excitability, muscle weakness, constipation, confusion, and renal calculi.

Hypermagnesemia Emergency Antidote

IV Calcium Gluconate to reverse neuromuscular and cardiac depression.

Hypomagnesemia Cardiac Risk

Lethal cardiac dysrhythmias, specifically Torsades de Pointes.

Hypophosphatemia Cause

Refeeding Syndrome in malnourished patients, driving phosphate rapidly into cells.

Third-Spacing Mechanism

Vascular fluid shifts into body cavities, becoming trapped and unavailable for circulation.

Hypovolemia Lab Findings

Elevated Hematocrit (Hct), elevated BUN, and elevated Urine Specific Gravity (>1.030).

Hypervolemia Clinical Presentation

Rapid weight gain, JVD, bilateral crackles, dyspnea, bounding pulses, and peripheral edema.

Most Sensitive Indicator of Fluid Status

Daily weight measurements (1 kg equals approximately 1 liter of fluid).

Orthostatic Hypotension Threshold

Systolic drop >=20 mmHg, diastolic drop >=10 mmHg, or HR increase >=20 bpm.

Isotonic IV Solutions Examples

0.9% Normal Saline, Lactated Ringer's, and D5W (in bag).

Hypotonic IV Solution Effect

Shifts water from ECF into cells, causing them to swell.

Contraindication for Hypotonic IV Fluids

Patients with increased intracranial pressure (ICP), severe head injury, or cerebral edema.

Hypertonic IV Solution Effect

Shifts water out of cells into ECF, causing cells to shrink.

Infiltration Assessment Findings

Cool skin, pale/blanched appearance, swelling, and slowed infusion rate.

Phlebitis Assessment Findings

Erythema, warmth, tenderness, and a palpable venous cord along the vein.

Air Embolism Emergency Position

Left-sided Trendelenburg position to trap air in the right ventricle apex.

NCLEX Priority for IV Complications

Stop the infusion and assess the patient immediately before taking other action.