Parathyroid surgery is a fairly common procedure. Undergoing a parathyroidectomy, the removal of the parathyroids, is usually a decision made by the patient and surgeon after enduring severe symptoms related to hyperparathyroidism (excess parathyroid hormone release) and all other medical options are exhausted. The parathyroids--four small glands located beneath the thyroid in the lower portion of the neck--release the parathyroid hormone (PTH) to regulate calcium and phosphate. Removal of the parathyroid glands is not without risk, though complications are rare, occurring in less than one percent of parathyroidectomy patients.
Recurrnet Laryngeal Nerve Damage
Damage to the recurrent laryngeal nerve is a rare complication of parathyroid surgery. It is also the most damaging. The recurrent laryngeal nerve is a branch of the larger vagus nerve that travels from the head to the diaphragm and passing through the neck. The recurrent laryngeal nerve is one of the smaller branches that provides motor function. Innervating the vocal box or vocal cords, damage to this nerve causes irreversible hoarseness and voice changes. Removal of all or a portion of the four parathyroid glands increases the risk of this complication. Avoiding damage to this nerve is directly correlated to a surgeon's experience, according to The American Association of Clinical Endocrinologists. A complex anatomical structure encountered during surgery, due to supernumerary (misplaced) or multiple parathyroids and parathyroid cancer, can also increase the risk of recurrent laryngeal damage.
Hungry Bone Syndrome
One of the major functions of PTH is to cause bones to release their stores of calcium and phosphate for cellular use. Like in all hormones, small changes in serum levels of hormonal triggers can cause large effects. Shifts in calcium and phosphate balance arise when the parathyroid gland is removed and PTH is no longer present. Bones react to this abrupt disturbance of balance by aggressively consuming serum calcium and phosphate. This is known as Hungry Bone Syndrome. Since the bones no longer break down, bone formation occurs unopposed. Hungry Bone Syndrome is seen most commonly in patients with prolonged hyperparathryoidism and with extremely high preoperative PTH levels (usually elderly patients).
Hypocalcemia
Calcium and phosphate are directly involved in muscle contraction and nerve conduction. However, big changes cause imbalance that are not without consequence, as reported by the Cleveland Clinic. Symptoms of hypocalcemia (low serum calcium levels) may or may not be present, depending on the severity, duration and rapidity of calcium decrease.
Neuropsychiatric symptoms resulting from decreased calcium concentration include seizures, dementia, slowed thinking, anxiety and depression.
Increased neuromuscular sensitivity due to low serum calcium may have symptoms such as tingling in fingers and toes from muscle stiffness, pain and spasms. Autonomic dysfunction may appear, and smooth muscle contraction may be disrupted, resulting in biliary colic, excessive sweating and laryngeal spasms.
Prolonged hypocalcemia may have devastating cardiovascular repercussions. Heart failure, hypotension (low blood pressure) and prolonged conduction of muscle contractions are serious side of effects of hypocalcemia.
Severe cases of prolonged hypocalcemia may cause cataracts, hyperpigmentation of the skin, dermatitis, eczema, low gastric acid production and a decrease in other essential elements.
