Parathyroidectomy
Parathyroidectomy, the surgical removal of one or more of the four parathyroid glands, treats primary hyperparathyroidism. In this disorder, the parathyroids secrete excessive amounts of parathyroid hormone (PTH), causing high serum calcium and low serum phosphorus levels.
The number of glands removed depends on the underlying cause of excessive PTH secretion. For example, if the patient has a single adenoma, excision of the affected gland corrects the problem. If more than one gland is enlarged, subtotal parathyroidectomy (removal of the three largest glands and part of the fourth gland) can correct hyperparathyroidism. The remaining glandular segment decreases the risk of postoperative hypoparathyroidism and resulting hypocalcemia because it resumes normal function.
Total parathyroidectomy is necessary when glandular hyperplasia results from cancer. In this case, the patient will require lifelong treatment for hypoparathyroidism. The physician may also perform subtotal thyroidectomy along with parathyroidectomy if he can’t locate the abnormal tissue or adenoma and suspects an intrathyroid lesion.
Serum calcium levels typically decrease within 24 to 48 hours after surgery and become normal within 4 to 5 days.
Procedure
After the patient is anesthetized, the physician makes a cervical neck incision and exposes the thyroid gland. He then locates the four parathyroids (usually within ¾″ [2 cm] above or below the point where the recurrent laryngeal nerve and the inferior thyroid artery cross) and identifies and tags them.
If he can’t find one of them, he’ll do a cervical thymectomy and thyroid lobectomy on the side where the gland is missing and send a sample for an immediate frozen section. If the missing gland isn’t found in the removed tissue, the physician may stop the procedure and order localization studies before a second surgery. Alternatively, he may continue surgery by opening the sternum and exploring the mediastinum for the missing gland.
When he has found all four glands, he examines them for hyperplasia and removes the affected ones. The surgeon tags the remaining glands or any of the gland that isn’t removed (remnant). Before he sutures the incision, he inserts a Penrose drain or a closed wound drainage device. (See What happens in parathyroidectomy, page 664.)
The surgeon should document the number and location of glands identified and removed so postoperative treatment can be planned for the patient’s specific needs.
