Fluid & Electrolyte Imbalance Quiz

Fluid & Electrolyte Imbalance

• Total body water is 60% of body weight
• Intracellular water is 40% of body weight
• Extracellular water is 20% of body weight
• Interstitial fluid - 28 liters
• Plasma - 3.5 liters
• Transcellular fluid - 1 liter
• Daily water gain = ~2500 mL
• Daily water loss = ~2500 mL

Fluid Volume Deficit (Hypovolemia, Isotonic Dehydration)

• Common causes: Hemorrhage, vomiting, diarrhea, burns, diuretic therapy, fever, impaired thirst
• Clinical manifestations: Weight loss, thirst, orthostatic changes in pulse rate and blood pressure, weak rapid pulse, decreased urine output, dry mucous membranes, poor skin turgor
• Orthostatic hypotension: blood pressure drop over 20 mm Hg systolic or 10 mg Hg diastolic when moving from sitting to standing position
• Lab findings: Increased HGB, HCT, urine specific gravity, BUN, and creatinine

Fluid Volume Excess (FVE)

• Common causes: Congestive heart failure, early renal failure, IV therapy, excessive sodium ingestion, SIADH, Corticosteroid use
• Clinical manifestations: Increased blood pressure, edema, weight gain, bounding pulse, venous distention, pulmonary edema, dyspnea, orthopnea, crackles
• Lab findings: Decreased HGB, HCT, and urine specific gravity

Urine Specific Gravity

• Normal range: 1.002 - 1.030
• High specific gravity (>1.030) indicates dehydration.
• Low specific gravity (<1.002) suggests kidney's inability to concentrate urine, often associated with fluid volume excess.

Treatment Fluid Volume Deficit (FVD)

• Fluid Management:
  • Mild to moderate dehydration: Correct by oral fluid replacement
  • Oral rehydration therapy: Solutions containing glucose and electrolytes (e.g., Pedialyte)
  • IV therapy: Type of fluid depends on the type of dehydration and the client's cardiovascular status

Treatment Fluid Volume Excess (FVE)

• Drug therapy: Diuretics (if renal failure is not the cause)
• Restriction of sodium and saline intake
• Strict I/O
• May restrict PO fluids
• Daily weight monitoring

More to Consider

• Age (infants, older adults)
• Prior medical history (acute, chronic illnesses)
• Environmental factors (diet, lifestyle, medications)

Physical Assessment

• Body systems assessment
• I&O monitoring
• Weight monitoring
• Lab values

Gerontological Considerations

• The elderly are more sensitive to fluid volume changes.
• Skin turgor is less reliable in elderly patients.
• Elderly patients may restrict fluid intake to prevent incontinence.
• Fluid loss needs to be replaced more slowly and cautiously in the elderly.

Electrolyte Imbalance

Potassium

• Regulates muscle contraction, especially the heart
• Normal levels: 3.5-5.2 mEq/L in adults

Hypokalemia (<3.5 mEq/L)

• Pathophysiology: Decrease in potassium causes decreased cell excitability and responsiveness to normal stimuli.
• Contributing Factors: Diuretics, shift into cells, digoxin, water intoxication, corticosteroids, diarrhea, vomiting
• Clinical manifestations: Shallow respirations, irritability, confusion, weakness, arrhythmias, lethargy, thready pulse, decreased intestinal motility

Hyperkalemia (>5.2 mEq/L)

• Pathophysiology: Increased potassium causes increased cell excitability.
• Contributing factors: Increase in K+ intake, renal failure, K+ sparing diuretics, shift of K+ out of cells
• Clinical manifestations: Muscle cramps, weakness leading to paralysis, drowsiness, EKG changes, dysrhythmias, abdominal cramping, diarrhea, oliguria

Hypocalcemia (<9 mg/dL)

• Contributing factors: Decreased oral intake, lactose intolerance, decreased vitamin D intake, end-stage renal disease, diarrhea, acute pancreatitis, hyperphosphatemia, immobility, removal or destruction of parathyroid gland
• Clinical Manifestations/Assessment findings: Irritable muscle twitches, positive Trousseau's sign, positive Chvostek's sign, respiratory failure due to muscle tetany, decreased heart rate, decreased blood pressure, diminished peripheral pulse, increased motility, increased bowel sounds, diarrhea
• Interventions/Treatment: Calcium supplements, vitamin D, high calcium diet, and seizure precautions.

Hypercalcemia (>10.5 mg/dL)

• Contributing factors: Excessive calcium intake, excessive vitamin D intake, renal failure, hyperparathyroidism, malignancy, hyperthyroidism
• Clinical Manifestations/Assessment findings: Disorientation, lethargy, coma, profound muscle weakness, ineffective respiratory movement, increased heart rate, increased blood pressure, bounding peripheral pulses, positive Homan's sign, decreased motility, decreased bowel sounds, constipation, increased urine output, formation of renal calculi
• Interventions/Treatment: Eliminate calcium administration, isotonic NaCl (increase excretion of calcium), diuretics, calcium reabsorption inhibitors (phosphorus), cardiac monitoring

Hypomagnesemia (<1.4 mEq/L)

• Contributing factors: Malnutrition, starvation, diuretics, aminoglycoside antibiotics, hyperglycemia, insulin administration
• Clinical findings: Positive Trousseau's sign, positive Chvostek's sign, hyperreflexia, seizures, ECG changes, dysrhythmias, high blood pressure, shallow breathing, decreased motility, anorexia, nausea
• Interventions: Eliminate contributing drugs, IV magnesium sulfate, assess Deep Tendon Reflexes (DTRs) hourly with magnesium sulfate, diet therapy

Hypermagnesemia (>2.0 mEq/L)

• Contributing factors: Increased magnesium intake, decreased renal excretion
• Clinical findings: Reduced or weak deep tendon reflexes (DTRs), weak voluntary muscle contractions, drowsiness, bradycardia, peripheral vasodilation, hypotension, ECG changes
• Interventions: Eliminate contributing drugs, administer diuretics, calcium gluconate to reverse cardiac effects, diet restrictions

Sodium (Na)

• Normal levels: 135-145 mEq/L

Hyponatremia (<135 mEq/L)

• Contributing factors: Excessive diaphoresis, wound drainage, NPO status, CHF, low salt diet, renal disease, diuretics
• Clinical findings: Generalized skeletal muscle weakness, headache, personality changes, shallow respirations, cardiac changes (depending on fluid volume), increased gastrointestinal motility, nausea, explosive diarrhea, increased urine output
• Interventions/Treatment: Restore Na levels to normal, increase oral sodium intake, restrict oral fluid intake, dont correct too quickly (12 mEq in 24 hours). If excess fluid, restrict fluids.

Hypernatremia (>145 mEq/L)

• Contributing factors: Hyperaldosteronism, renal failure, corticosteroids, increase in oral Na intake, Na containing IV fluids, decreased urine output with increased urine concentration, diarrhea, dehydration, fever, hyperventilation.
• Clinical findings: Spontaneous muscle twitches, irregular contractions, skeletal muscle weakness, diminished deep tendon reflexes, pulmonary edema, heart rate and blood pressure depending on vascular volume, dry flaky skin, edema related to fluid volume changes, Decreased urine output, Increased urine specific gravity
• Interventions/Treatment: Fluid volume deficit (FVD): .45% NSS. if caused by both Na and fluid loss: administer NaCl, if inadequate renal excretion of sodium, administer diuretics. Mild: Ensure water intake.