Fluids & Electrolytes II

• Calcium

  Stored in the bones, absorbed in the GI system, and excreted by the kidneys<|>Plays an important role in bones, teeth, nerves, and muscles<|>Important for coagulation<|>Is controlled by PTH and Vitamin D<|>Has an inverse relationship with phosphorus<|>Normal calcium: 9.0 - 10.5 mg/dL
• Causes of Hypercalemia

  Excessive intake of calcium<|>Hyperparathyroidism<|>Excessive intake of Vitamin D<|>Vitamin D toxicity<|>Cancer of the bones<|>Immobility
• Hypercalcemia assessment

  • Neuromuscular: Weakness, Flaccidity, Decreased deep tendon reflexes
  • Cardiovascular: Bradycardia, Cyanosis, Deep vein thrombosis
  • Gastrointestinal: Decreased peristalsis, Hypoactive bowel sounds, Abdominal pain, Nausea, Vomiting, Constipation, Kidney stones
  • Neuro: Fatigue, Decreased LOC
• Causes of Hypocalcemia

  Renal failure<|>Acute pancreatitis<|>Malnutrition<|>Malabsorption: Celiac disease, Crohn's disease<|>Alcoholism<|>Bulimia<|>Vitamin D deficiency<|>Hypoparathyroidism<|>Hyperphosphatemia
• Hypocalcemia assessment

  • Neuromuscular: Irritability, Hallucinations, Paresthesias, Tetany, Seizures, Muscle spasms, Chvostek's sign, Trousseau's sign
  • Gastrointestinal: Hyperactive bowel sounds, Cramping, Diarrhea
  • Misc: Weak bones (increased risk of fractures), Weak/brittle nails, Arrhythmias (Ventricular Tachycardia)
• Hypocalcemia treatment

  1. PO calcium supplements (administer with Vitamin D to increase absorption)

  2. IV calcium supplements

  3. Calcium rich diet
• Phosphorus

  Major role is in cellular metabolism and energy production (ATP)<|>Makes up the phospholipid bilayer of cell membranes<|>Large component of bones and teeth<|>Has an inverse relationship with Calcium<|>Normal phosphorus: 3.0-4.5 mg/dL
• Hyperphosphatemia

  Excessive dietary intake of phosphorus<|>Tumor lysis syndrome<|>Renal failure<|>Hypoparathyroidism → Hypocalcemia → Hyperphosphatemia
• Symptoms of hyperphosphatemia are related to the hypocalcemia secondary to hyperphosphatemia
• Hyperphosphatemia treatment

  1. Phosphate binders (given with food)

  2. Manage hypocalcemia
• Causes of Hypophosphatemia

  Malnutrition<|>Alcoholism<|>TPN<|>Hyperparathyroidism → hypercalcemia → hypophosphatemia
• Symptoms of hypophosphatemia are related to the hypercalcemia secondary to hypophosphatemia
• Hypophosphatemia treatment

  1. Treat the cause

  2. Phosphorus replacement (PO or IV given slowly)

  3. Phosphorus rich diet

  4. Diet low in calcium
• Magnesium

  Stored in the bones and cartilage<|>Plays a major role in skeletal muscle contraction<|>Important for ATP formation<|>Activates vitamins<|>Necessary for cellular growth<|>Is directly related to calcium<|>Normal magnesium: 1.5-2.5 mg/dL
• Causes of Hypermagnesemia

  Excessive dietary intake<|>Too many magnesium containing medications<|>Over-correction of hypomagnesemia<|>Renal failure
• Hypermagnesemia assessment

  • Neuromuscular: Weakness, Shallow breathing, Slowed reflexes, Decreased deep tendon reflexes
  • Cardiovascular: Bradycardia, Hypotension, Vasodilation (Flushed, Feel warm)
  • Neuro: Drowsy, Lethargy, Coma
• Hypermagnesemia treatment

  1. Treat the cause

  2. Hold any fluids or meds containing Mag

  3. Loop diuretics

  4. Calcium gluconate

  5. Dialysis
• Causes of Hypomagnesemia

  Alcoholism<|>Malnutrition<|>Malabsorption<|>Hypoparathyroidism<|>Hypocalcemia<|>Diarrhea
• Hypomagnesemia assessment

  • Neuromuscular: Numbness, Tingling, Cramping, Tetany, Seizures, Increased deep tendon reflexes
  • Neuro: Psychosis, Confusion
  • CV: Torsades de pointes
  • Gastrointestinal: Nausea, Vomiting, Abdominal cramps, Anorexia
• Hypomagnesemia treatment

  1. Treat the cause

  2. Monitor cardiac rhythm

  3. Administer magnesium (PO - Magnesium hydroxide or IV - given very slowly)