Hyperparathyroidism

Learning objectives

Describe hyperparathyroidism
Recognize the symptoms and signs of hypercalcemia, related to hyperparathyroidism
Anesthetic management of a patient with hyperparathyroidism

Hyperparathyroidism (HPT) is a condition in which the parathyroid glands produce too much parathyroid hormone (PTH)
PTH plays an important role in maintaining normal calcium homeostasis
The main effector sites responding directly or indirectly to PTH are the intestines, kidneys, and bone
HPT ultimately results in hypercalcemia

Primary HPT: Hyperfunction of the parathyroid glands (i.e., adenoma, carcinoma, or hyperplasia) leading to an overproduction of PTH
Secondary HPT: Appropriate compensatory response of the parathyroid glands to secrete more PTH in response to a condition (i.e., chronic kidney disease, vitamin D deficiency) that produces hypocalcemia
Tertiary HPT: Long-standing secondary HPT starts to behave like primary HPT, usually associated with advanced kidney failure
Ectopic HPT: Secretion of PTH by tissues other than the parathyroid glands

The symptoms of HPT are caused by hypercalcemia:

Cardiovascular: Hypertension, shortened QT interval, prolonged PR interval, hypovolemia, conduction blockade
Neurological: Mental status changes, weakness, lethargy
Respiratory: Potential respiratory muscle weakness, poor clearance of secretions
Musculoskeletal: Muscle weakness, osteoporosis, pathological fractures, bone pains
Gastrointestinal: Abdominal pain, peptic ulcer, pancreatitis, nausea/vomiting, ↑ aspiration risk
Renal: Polyuria, polydipsia, renal stones, renal failure
Hematopoietic: Anemia

Primary HPT: Parathyroidectomy
Secondary HPT: Treat underlying cause (i.e., chronic kidney failure, vitamin D deficiency)
Tertiary HPT: Parathyroidectomy
Calcimimetics are used in patients with primary HPT unable to undergo parathyroidectomy and for patients with secondary HPT on dialysis