Fluids & Electrolytes I

• Prefixes

  Hyper = more<|>Iso = same<|>Eu = normal<|>Hypo = less
• Sodium (Na+)

  The most abundant extracellular cation<|>Regulates water in the cells of the body<|>Water follows sodium<|>Important in the brain, nerves, and muscle cells<|>Normal sodium: 135 - 145 mEq/L
• Hypernatremia

  • Euvolemic: Decreased water with near normal sodium
  • Hypovolemic: Decreased water AND sodium, but MORE water loss
  • Hypervolemic: Increased sodium AND water, but MORE sodium
• Causes of Hypernatremia

  1. Euvolemic: Increased insensible water loss, Diabetes insipidus

  2. Hypovolemic: Dehydration, NPO, Diarrhea, Vomiting, Burns, Diuretics

  3. Hypervolemic: Hypertonic IVF, Sodium bicarbonate, Increased sodium intake, Corticosteroids, Cushing's, Hyperaldosteronism
• Assessment of Hypernatremia

  • Neuro: Restless, Agitated, Lethargic, Drowsy, Stupor, Coma
  • CV: Fever, Hypervolemic (Edema, Hypertension, Bounding pulses), Hypovolemic (Hypotension, Weak pulses)
  • Musculoskeletal: Twitching, Cramps, Weakness
  • Other: Flushed skin, Decreased UOP, Dry mouth
• Treatment of Euvolemic Hypernatremia

  Free water administration based on free water deficit, PO intake better than IV
• Treatment of Hypovolemic Hypernatremia

  Isotonic fluid administration (NS is "relatively hypotonic" to the body)
• Treatment of Hypervolemic Hypernatremia

  Find and discontinue causative agent, Loop diuretics, Free water administration
• Key point in treatment: Monitor neuro status, Correct imbalance SLOWLY - Risk for cerebral edema
• Hyponatremia

  • Euvolemic: Water in the body increases, but sodium particles stay the same
  • Hypervolemic: Water in the body increases to point of hypervolemia, diluting sodium
  • Hypovolemic: Water and sodium are both lost
• Causes of Euvolemic Hyponatremia

  • SIADH
  • Adrenal insufficiency
  • Addison's disease
  • Polydipsia
  • Excessive hypotonic IVF
  • Low dietary intake of sodium
• Causes of Hypervolemic Hyponatremia

  • CHF
  • Kidney failure
  • Nephrotic syndrome
  • Liver failure
  • Water intoxication
• Causes of Hypovolemic Hyponatremia

  • Vomiting
  • Diarrhea
  • NG suction
  • Diuretics
  • Burns
  • Excessive sweating
• Assessment of Hyponatremia

  • Neuro: Seizures, Confusion, Lethargy, Stupor, Cerebral edema, Increased ICP
  • Musculoskeletal: Abdominal cramps, Weakness, Shallow respirations, Decreased deep tendon reflexes, Muscle spasms, Orthostatic hypotension
  • GI/GU: Loss of appetite, Hyperactive bowel sounds
  • CV: Hypovolemia (Weak pulse, Tachycardia, Hypotension, Dizziness), Hypervolemia (Bounding pulses, Hypertension)
• Treatment of Euvolemic Hyponatremia

  Restrict free water, Osmotic diuretics, Sodium tablets, High salt diet
• Treatment of Hypovolemic Hyponatremia

  Mild - 0.9% NS (isotonic), Severe - 3% NS (hypertonic)
• Replacing sodium slowly, 0.5 mEq/hr, to avoid fluid shifts and complications like cerebral edema and increased ICP
• Chloride (Cl-)

  Most abundant extracellular anion<|>Works with sodium to maintain fluid balance<|>Binds with hydrogen ions to form stomach acid - HCl<|>Inversely related to bicarbonate<|>Directly related to sodium and potassium<|>Normal chloride: 98-106 mEq/L
• Hyperchloremia

  • Causes: Volume overload (CHF, Water intoxication), Salt losses (Burns, Sweating, Vomiting, Diarrhea, Cystic Fibrosis, Addison's Disease)
  • Assessment: Signs and symptoms of hyponatremia
  • Treatment: Treat underlying cause, Correct imbalance with Normal Saline - 0.9% NaCl, Monitor all electrolytes
• Normal Saline

  0.9% NaCL
• Monitor all electrolytes

  • It's usually not the only imbalance!
• Maintenance IV fluids

  • 3% NS
  • Normal Saline IVF
  • Lactated Ringers IVF
  • D5NS
  • 0.45% Normal Saline
• Lactated Ringers IVF

  The appropriate choice for IV fluids for the client with hyperchloremia
• Potassium

  Found mostly inside the cells - most abundant intracellular cation<|>Normal value is for serum level - the potassium in the blood, outside of the cells<|>Responsible for nerve impulse conduction<|>Important in muscle contraction - heart muscle and skeletal muscle<|>Important in acid-base balance
• Normal potassium

  3.5 - 5.0 mEq/L
• Causes of hyperkalemia

  • Too much potassium moved from intracellular to extracellular (burns, tissue damage, diabetic ketoacidosis)
  • Too much total potassium (renal failure, excessive K+ intake)
  • Medications (ACE inhibitors, potassium-sparing diuretics)
• Assessment of hyperkalemia

  • Muscle weakness
  • Numbness
  • Shallow respirations
  • Cramping
  • Hyperactive bowel sounds
  • Diarrhea
  • Impaired contractility (weak pulses, bradycardia, hypotension)
• EKG changes in hyperkalemia

  Wide, flat P waves<|>Prolonged PR interval<|>Widened QRS interval<|>Depressed ST segment<|>Tall, peaked T waves
• Treatment of hyperkalemia

  1. Drive potassium into cells (D5W + regular insulin, albuterol, bicarbonate)

  2. Reduce total body potassium (kayexalate, diuretics, dialysis)
• Nursing considerations for hyperkalemia

  • Monitor cardiac rhythm
  • Discontinue any potassium supplements
  • Potassium restricted diet
  • IV Calcium gluconate or chloride
• Causes of hypokalemia

  • Potassium wasting drugs (laxatives, diuretics, corticosteroids)
  • Inadequate K intake (NPO, poor diet, anorexia nervosa, bulimia nervosa, alcoholism)
  • Diluting K in the blood - too much water (polydipsia, excessive IVF administration)
  • Fluid loss (NGT suction, vomiting, wound drainage)
• Assessment of hypokalemia

  • Weakness + fatigue (weak muscles, cramps, decreased deep tendon reflexes, flaccidity, shallow respirations, decreased bowel sounds)
  • Weak heart (orthostatic hypotension, weak, thready pulse, cardiac dysrhythmias)
• EKG changes in hypokalemia

  Slightly peaked P wave<|>Slightly prolonged PR interval<|>ST depression<|>Flat/shallow/inverted T waves<|>Prominent u-waves
• Treatment of hypokalemia

  1. Prevent arrhythmias (place on cardiac telemetry, hold digoxin)

  2. Prevent further K loss (hold furosemide or other potassium wasting drugs)

  3. Give more potassium (IV potassium supplements, oral potassium supplements, diet rich in potassium)
• IV potassium supplement administration

  • Never give IV push
  • Give according to instructions; slowly
  • Monitor IV site very carefully
• EKG signs of hyperkalemia

  • Widened QRS interval
  • Tall, peaked T waves
  • Prolonged PR interval