Hyperparathyroidism Lecture by Sarah from RegisterNurseRN.com

Definition

• Excessive secretion of PTH (Parathyroid Hormone) by the parathyroid gland.
• Results in:
  • Hypercalcemia (high calcium levels)
  • Hypophosphatemia (low phosphate levels)

Parathyroid Gland Function

• Located in the neck behind the thyroid gland.
• Contains 4 parathyroid glands.
• PTH is released when blood calcium levels are low (< 8.6 mg/dL).
• Normal blood calcium levels: 8.6 to 10 mg/dL.
• PTH affects kidneys and bones.
  • Kidneys: Reabsorb calcium, excrete phosphate, activate Vitamin D.
  • Bones: Stimulates osteoclasts which break down bones, releasing calcium into blood.

Causes

Primary Causes

• Problems with the parathyroid gland itself:
  • Non-cancerous adenomas (most common).
  • Hyperplasia of the gland (enlarged, overactive glands).
  • Cancerous growth on the parathyroid.

Secondary Causes

• Diseases causing malfunction of parathyroid gland:
  • Chronic renal failure (overworking the parathyroid due to low calcium levels).
  • Persistent hypocalcemia (overworking the parathyroid).
  • Vitamin D deficiency (leading to low calcium absorption).

Signs and Symptoms

• Result from high calcium levels affecting bone health, muscle, and nerve function.
• Bone-related: Osteoporosis, bone fractures due to bone resorption.
• Renal/Kidney-related:
  • Renal calculi (stones) due to high calcium levels and dehydration.
  • Frequent urination, leading to dehydration and potentially more stones.
• GI-related: Constipation, nausea, vomiting, epigastric pain (due to increased gastric acid).
• Cardiac: EKG changes, specifically a short QT interval.

Nursing Interventions

• Monitor vital signs, EKG, urine (for stones), calcium, and phosphate levels.
• Manage intake and output, promote fluid intake to dilute urine.
• Encourage diet low in calcium and high in phosphate (except in renal patients).
• Procedures: Parathyroidectomy (removal of enlarged or tumorous glands).
  • Monitor respiratory status, place in semi-Fowler's position.
  • Have emergency equipment like trach kit, suction, oxygen ready.
  • Watch for signs of hypocalcemia (tingling, numbness, twitching, positive Trousseau's and Chvostek's signs).
  • Monitor for laryngeal nerve damage (difficulty speaking, hoarseness).

Medications

• Calcimimetics (e.g., Cinacalcet)
  • Deceive parathyroid gland to stop releasing PTH by mimicking calcium.
  • Decreases PTH, calcium, and phosphate levels.
• Calcitonin
  • Reduces calcium levels by inhibiting osteoclast activity and promoting excretion of calcium by the kidneys.
  • Protects bones.
• Loop Diuretics (e.g., Lasix)
  • Lowers calcium by inhibiting calcium resorption in kidneys.
  • Monitor potassium levels.
• Bisphosphonates (e.g., Pamidronate, Alendronate/Fosamax)
  • Protect bones by slowing osteoclast activity, increase osteoblast activity.
  • Fosamax: Take on an empty stomach, with a full glass of water, sit up for 30 minutes after taking, and wait 30 minutes before taking other meds or food.

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